331. What is XSL
Extensible Stylesheet Language. A standard that lets
you do the following: Specify an addressing mechanism,
so that you can identify the parts of an XML document
that a transformation applies to (XPath). Specify tag
conversions, so that you can convert XML data into
different formats (XSLT). Specify display
characteristics, such page sizes, margins, and font
heights and widths, as well as the flow objects on
each page. Information fills in one area of a page and
then automatically flows to the next object when that
area fills up. That allows you to wrap text around
pictures, for example, or to continue a newsletter
article on a different page (XSL-FO).
332. What is XSL-FO
A subcomponent of XSL used for describing font sizes,
page layouts, and how information flows from one page
to another.
333. What is XSLT
XSL Transformations. An XML document that controls the
transformation of an XML document into another XML
document or HTML. The target document often has
presentation-related tags dictating how it will be
rendered by a browser or other presentation mechanism.
XSLT was formerly a part of XSL, which also included a
tag language of style flow objects.
334. What is XSLTC
A compiling version of XSLT.
335. What is binary entity
A general entity that contains something other than
XML. By its nature, an unparsed entity contains binary
data.
336. What is component (JavaServer Faces technology)
A user interface control that outputs data to a client
or allows a user to input data to a JavaServer Faces
application.
Friday, November 9, 2007
J2EE Interview questions and answers
321. What is well-formed
An XML document that is syntactically correct. It does
not have any angle brackets that are not part of tags,
all tags have an ending tag or are themselves
self-ending, and all tags are fully nested. Knowing
that a document is well formed makes it possible to
process it. However, a well-formed document may not be
valid. To determine that, you need a validating parser
and a DTD.
322. What is Xalan
An interpreting version of XSLT.
323. What is XHTML
An XML look-alike for HTML defined by one of several
XHTML DTDs. To use XHTML for everything would of
course defeat the purpose of XML, because the idea of
XML is to identify information content, and not just
to tell how to display it. You can reference it in a
DTD, which allows you to say, for example, that the
text in an element can contain < em > and < b > tags
rather than being limited to plain text.
324. What is XLink
The part of the XLL specification that is concerned
with specifying links between documents.
325. What is XLL
The XML Link Language specification, consisting of
XLink and XPointer.
326. What is XML
Extensible Markup Language. A markup language that
allows you to define the tags (markup) needed to
identify the content, data, and text in XML documents.
It differs from HTML, the markup language most often
used to present information on the Internet. HTML has
fixed tags that deal mainly with style or
presentation. An XML document must undergo a
transformation into a language with style tags under
the control of a style sheet before it can be
presented by a browser or other presentation
mechanism. Two types of style sheets used with XML are
CSS and XSL. Typically, XML is transformed into HTML
for presentation. Although tags can be defined as
needed in the generation of an XML document, a
document type definition (DTD) can be used to define
the elements allowed in a particular type of document.
A document can be compared by using the rules in the
DTD to determine its validity and to locate particular
elements in the document. A Web services application's
J2EE deployment descriptors are expressed in XML with
schemas defining allowed elements. Programs for
processing XML documents use SAX or DOM APIs.
327. What is XML registry
An infrastructure that enables the building,
deployment, and discovery of Web services. It is a
neutral third party that facilitates dynamic and
loosely coupled business-to-business (B2B)
interactions.
328. What is XML Schema
The W3C specification for defining the structure,
content, and semantics of XML documents.
329. What is XPath
An addressing mechanism for identifying the parts of
an XML document.
330. What is XPointer
The part of the XLL specification that is concerned
with identifying sections of documents so that they
can be referenced in links or included in other
documents.
An XML document that is syntactically correct. It does
not have any angle brackets that are not part of tags,
all tags have an ending tag or are themselves
self-ending, and all tags are fully nested. Knowing
that a document is well formed makes it possible to
process it. However, a well-formed document may not be
valid. To determine that, you need a validating parser
and a DTD.
322. What is Xalan
An interpreting version of XSLT.
323. What is XHTML
An XML look-alike for HTML defined by one of several
XHTML DTDs. To use XHTML for everything would of
course defeat the purpose of XML, because the idea of
XML is to identify information content, and not just
to tell how to display it. You can reference it in a
DTD, which allows you to say, for example, that the
text in an element can contain < em > and < b > tags
rather than being limited to plain text.
324. What is XLink
The part of the XLL specification that is concerned
with specifying links between documents.
325. What is XLL
The XML Link Language specification, consisting of
XLink and XPointer.
326. What is XML
Extensible Markup Language. A markup language that
allows you to define the tags (markup) needed to
identify the content, data, and text in XML documents.
It differs from HTML, the markup language most often
used to present information on the Internet. HTML has
fixed tags that deal mainly with style or
presentation. An XML document must undergo a
transformation into a language with style tags under
the control of a style sheet before it can be
presented by a browser or other presentation
mechanism. Two types of style sheets used with XML are
CSS and XSL. Typically, XML is transformed into HTML
for presentation. Although tags can be defined as
needed in the generation of an XML document, a
document type definition (DTD) can be used to define
the elements allowed in a particular type of document.
A document can be compared by using the rules in the
DTD to determine its validity and to locate particular
elements in the document. A Web services application's
J2EE deployment descriptors are expressed in XML with
schemas defining allowed elements. Programs for
processing XML documents use SAX or DOM APIs.
327. What is XML registry
An infrastructure that enables the building,
deployment, and discovery of Web services. It is a
neutral third party that facilitates dynamic and
loosely coupled business-to-business (B2B)
interactions.
328. What is XML Schema
The W3C specification for defining the structure,
content, and semantics of XML documents.
329. What is XPath
An addressing mechanism for identifying the parts of
an XML document.
330. What is XPointer
The part of the XLL specification that is concerned
with identifying sections of documents so that they
can be referenced in links or included in other
documents.
J2EE Interview questions and answers
311. What is Web component
A component that provides services in response to
requests; either a servlet or a JSP page.
312. What is Web container
A container that implements the Web component contract
of the J2EE architecture. This contract specifies a
runtime environment for Web components that includes
security, concurrency, life-cycle management,
transaction, deployment, and other services. A Web
container provides the same services as a JSP
container as well as a federated view of the J2EE
platform APIs. A Web container is provided by a Web or
J2EE server.
313. What is Web container, distributed
A Web container that can run a Web application that is
tagged as distributable and that executes across
multiple Java virtual machines running on the same
host or on different hosts.
314. What is Web container provider
A vendor that supplies a Web container.
315. What is Web module
A deployable unit that consists of one or more Web
components, other resources, and a Web application
deployment descriptor contained in a hierarchy of
directories and files in a standard Web application
format.
316. What is Web resource
A static or dynamic object contained in a Web
application that can be referenced by a URL.
317. What is Web resource collection
A list of URL patterns and HTTP methods that describe
a set of Web resources to be protected.
318. What is Web server
Software that provides services to access the
Internet, an intranet, or an extranet. A Web server
hosts Web sites, provides support for HTTP and other
protocols, and executes server-side programs (such as
CGI scripts or servlets) that perform certain
functions. In the J2EE architecture, a Web server
provides services to a Web container. For example, a
Web container typically relies on a Web server to
provide HTTP message handling. The J2EE architecture
assumes that a Web container is hosted by a Web server
from the same vendor, so it does not specify the
contract between these two entities. A Web server can
host one or more Web containers.
319. What is Web server provider
A vendor that supplies a Web server.
320. What is Web service
An application that exists in a distributed
environment, such as the Internet. A Web service
accepts a request, performs its function based on the
request, and returns a response. The request and the
response can be part of the same operation, or they
can occur separately, in which case the consumer does
not need to wait for a response. Both the request and
the response usually take the form of XML, a portable
data-interchange format, and are delivered over a wire
protocol, such as HTTP.
A component that provides services in response to
requests; either a servlet or a JSP page.
312. What is Web container
A container that implements the Web component contract
of the J2EE architecture. This contract specifies a
runtime environment for Web components that includes
security, concurrency, life-cycle management,
transaction, deployment, and other services. A Web
container provides the same services as a JSP
container as well as a federated view of the J2EE
platform APIs. A Web container is provided by a Web or
J2EE server.
313. What is Web container, distributed
A Web container that can run a Web application that is
tagged as distributable and that executes across
multiple Java virtual machines running on the same
host or on different hosts.
314. What is Web container provider
A vendor that supplies a Web container.
315. What is Web module
A deployable unit that consists of one or more Web
components, other resources, and a Web application
deployment descriptor contained in a hierarchy of
directories and files in a standard Web application
format.
316. What is Web resource
A static or dynamic object contained in a Web
application that can be referenced by a URL.
317. What is Web resource collection
A list of URL patterns and HTTP methods that describe
a set of Web resources to be protected.
318. What is Web server
Software that provides services to access the
Internet, an intranet, or an extranet. A Web server
hosts Web sites, provides support for HTTP and other
protocols, and executes server-side programs (such as
CGI scripts or servlets) that perform certain
functions. In the J2EE architecture, a Web server
provides services to a Web container. For example, a
Web container typically relies on a Web server to
provide HTTP message handling. The J2EE architecture
assumes that a Web container is hosted by a Web server
from the same vendor, so it does not specify the
contract between these two entities. A Web server can
host one or more Web containers.
319. What is Web server provider
A vendor that supplies a Web server.
320. What is Web service
An application that exists in a distributed
environment, such as the Internet. A Web service
accepts a request, performs its function based on the
request, and returns a response. The request and the
response can be part of the same operation, or they
can occur separately, in which case the consumer does
not need to wait for a response. Both the request and
the response usually take the form of XML, a portable
data-interchange format, and are delivered over a wire
protocol, such as HTTP.
J2EE Interview questions and answers
301. What is user (security)
An individual (or application program) identity that
has been authenticated. A user can have a set of roles
associated with that identity, which entitles the user
to access all resources protected by those roles.
302. What is user (security)
A valid XML document, in addition to being well
formed, conforms to all the constraints imposed by a
DTD. It does not contain any tags that are not
permitted by the DTD, and the order of the tags
conforms to the DTD's specifications.
303. What is validating parser
A parser that ensures that an XML document is valid in
addition to being well formed. See also parser.
304. What is value-binding _expression
A JavaServer Faces EL _expression that refers to a
property of a backing bean. A component tag uses this
_expression to bind the associated component's value or
the component instance to the bean property. If the
component tag refers to the property via its value
attribute, then the component's value is bound to the
property. If the component tag refers to the property
via its binding attribute then the component itself is
bound to the property.
305. What is virtual host
Multiple hosts plus domain names mapped to a single IP
address.
306. What is W3C
World Wide Web Consortium. The international body that
governs Internet standards. Its Web site is
http://www.w3.org/.
307. What is WAR file
Web application archive file. A JAR archive that
contains a Web module.
308. What is warning
A SAX parser warning is generated when the document's
DTD contains duplicate definitions and in similar
situations that are not necessarily an error but which
the document author might like to know about, because
they could be. See also fatal error, error.
309. What is Web application
An application written for the Internet, including
those built with Java technologies such as JavaServer
Pages and servlets, as well as those built with
non-Java technologies such as CGI and Perl.
310. What is Web application, distributable
A Web application that uses J2EE technology written so
that it can be deployed in a Web container distributed
across multiple Java virtual machines running on the
same host or different hosts. The deployment
descriptor for such an application uses the
distributable element.
An individual (or application program) identity that
has been authenticated. A user can have a set of roles
associated with that identity, which entitles the user
to access all resources protected by those roles.
302. What is user (security)
A valid XML document, in addition to being well
formed, conforms to all the constraints imposed by a
DTD. It does not contain any tags that are not
permitted by the DTD, and the order of the tags
conforms to the DTD's specifications.
303. What is validating parser
A parser that ensures that an XML document is valid in
addition to being well formed. See also parser.
304. What is value-binding _expression
A JavaServer Faces EL _expression that refers to a
property of a backing bean. A component tag uses this
_expression to bind the associated component's value or
the component instance to the bean property. If the
component tag refers to the property via its value
attribute, then the component's value is bound to the
property. If the component tag refers to the property
via its binding attribute then the component itself is
bound to the property.
305. What is virtual host
Multiple hosts plus domain names mapped to a single IP
address.
306. What is W3C
World Wide Web Consortium. The international body that
governs Internet standards. Its Web site is
http://www.w3.org/.
307. What is WAR file
Web application archive file. A JAR archive that
contains a Web module.
308. What is warning
A SAX parser warning is generated when the document's
DTD contains duplicate definitions and in similar
situations that are not necessarily an error but which
the document author might like to know about, because
they could be. See also fatal error, error.
309. What is Web application
An application written for the Internet, including
those built with Java technologies such as JavaServer
Pages and servlets, as well as those built with
non-Java technologies such as CGI and Perl.
310. What is Web application, distributable
A Web application that uses J2EE technology written so
that it can be deployed in a Web container distributed
across multiple Java virtual machines running on the
same host or different hosts. The deployment
descriptor for such an application uses the
distributable element.
J2EE Interview questions and answers
301. What is user (security)
An individual (or application program) identity that
has been authenticated. A user can have a set of roles
associated with that identity, which entitles the user
to access all resources protected by those roles.
302. What is user (security)
A valid XML document, in addition to being well
formed, conforms to all the constraints imposed by a
DTD. It does not contain any tags that are not
permitted by the DTD, and the order of the tags
conforms to the DTD's specifications.
303. What is validating parser
A parser that ensures that an XML document is valid in
addition to being well formed. See also parser.
304. What is value-binding _expression
A JavaServer Faces EL _expression that refers to a
property of a backing bean. A component tag uses this
_expression to bind the associated component's value or
the component instance to the bean property. If the
component tag refers to the property via its value
attribute, then the component's value is bound to the
property. If the component tag refers to the property
via its binding attribute then the component itself is
bound to the property.
305. What is virtual host
Multiple hosts plus domain names mapped to a single IP
address.
306. What is W3C
World Wide Web Consortium. The international body that
governs Internet standards. Its Web site is
http://www.w3.org/.
307. What is WAR file
Web application archive file. A JAR archive that
contains a Web module.
308. What is warning
A SAX parser warning is generated when the document's
DTD contains duplicate definitions and in similar
situations that are not necessarily an error but which
the document author might like to know about, because
they could be. See also fatal error, error.
309. What is Web application
An application written for the Internet, including
those built with Java technologies such as JavaServer
Pages and servlets, as well as those built with
non-Java technologies such as CGI and Perl.
310. What is Web application, distributable
A Web application that uses J2EE technology written so
that it can be deployed in a Web container distributed
across multiple Java virtual machines running on the
same host or different hosts. The deployment
descriptor for such an application uses the
distributable element.
An individual (or application program) identity that
has been authenticated. A user can have a set of roles
associated with that identity, which entitles the user
to access all resources protected by those roles.
302. What is user (security)
A valid XML document, in addition to being well
formed, conforms to all the constraints imposed by a
DTD. It does not contain any tags that are not
permitted by the DTD, and the order of the tags
conforms to the DTD's specifications.
303. What is validating parser
A parser that ensures that an XML document is valid in
addition to being well formed. See also parser.
304. What is value-binding _expression
A JavaServer Faces EL _expression that refers to a
property of a backing bean. A component tag uses this
_expression to bind the associated component's value or
the component instance to the bean property. If the
component tag refers to the property via its value
attribute, then the component's value is bound to the
property. If the component tag refers to the property
via its binding attribute then the component itself is
bound to the property.
305. What is virtual host
Multiple hosts plus domain names mapped to a single IP
address.
306. What is W3C
World Wide Web Consortium. The international body that
governs Internet standards. Its Web site is
http://www.w3.org/.
307. What is WAR file
Web application archive file. A JAR archive that
contains a Web module.
308. What is warning
A SAX parser warning is generated when the document's
DTD contains duplicate definitions and in similar
situations that are not necessarily an error but which
the document author might like to know about, because
they could be. See also fatal error, error.
309. What is Web application
An application written for the Internet, including
those built with Java technologies such as JavaServer
Pages and servlets, as well as those built with
non-Java technologies such as CGI and Perl.
310. What is Web application, distributable
A Web application that uses J2EE technology written so
that it can be deployed in a Web container distributed
across multiple Java virtual machines running on the
same host or different hosts. The deployment
descriptor for such an application uses the
distributable element.
J2EE Interview questions and answers
291. What is transaction isolation level
What is transaction isolation level The degree to
which the intermediate state of the data being
modified by a transaction is visible to other
concurrent transactions and data being modified by
other transactions is visible to it.
292. What is transaction manager
Provides the services and management functions
required to support transaction demarcation,
transactional resource management, synchronization,
and transaction context propagation.
293. What is Unicode
A standard defined by the Unicode Consortium that uses
a 16-bit code page that maps digits to characters in
languages around the world. Because 16 bits covers
32,768 codes, Unicode is large enough to include all
the world's languages, with the exception of
ideographic languages that have a different character
for every concept, such as Chinese. For more
information, see http://www.unicode.org/.
294. What is Universal Description, Discovery and
Integration (UDDI) project
An industry initiative to create a
platform-independent, open framework for describing
services, discovering businesses, and integrating
business services using the Internet, as well as a
registry. It is being developed by a vendor
consortium.
295. What is Universal Standard Products and Services
Classification (UNSPSC)
A schema that classifies and identifies commodities.
It is used in sell-side and buy-side catalogs and as a
standardized account code in analyzing expenditure.
296. What is unparsed entity
A general entity that contains something other than
XML. By its nature, an unparsed entity contains binary
data.
296. What is URI
Uniform resource identifier. A globally unique
identifier for an abstract or physical resource. A URL
is a kind of URI that specifies the retrieval protocol
(http or https for Web applications) and physical
location of a resource (host name and host-relative
path). A URN is another type of URI.
297. What is URL
Uniform resource locator. A standard for writing a
textual reference to an arbitrary piece of data in the
World Wide Web. A URL looks like this:
protocol://host/localinfo where protocol specifies a
protocol for fetching the object (such as http or
ftp), host specifies the Internet name of the targeted
host, and localinfo is a string (often a file name)
passed to the protocol handler on the remote host.
298. What is URL path
The part of a URL passed by an HTTP request to invoke
a servlet. A URL path consists of the context path +
servlet path + path info, where Context path is the
path prefix associated with a servlet context of which
the servlet is a part. If this context is the default
context rooted at the base of the Web server's URL
namespace, the path prefix will be an empty string.
Otherwise, the path prefix starts with a / character
but does not end with a / character. Servlet path is
the path section that directly corresponds to the
mapping that activated this request. This path starts
with a / character. Path info is the part of the
request path that is not part of the context path or
the servlet path
299. What is URN
Uniform resource name. A unique identifier that
identifies an entity but doesn't tell where it is
located. A system can use a URN to look up an entity
locally before trying to find it on the Web. It also
allows the Web location to change, while still
allowing the entity to be found.
300. What is user data constraint
Indicates how data between a client and a Web
container should be protected. The protection can be
the prevention of tampering with the data or
prevention of eavesdropping on the data.
What is transaction isolation level The degree to
which the intermediate state of the data being
modified by a transaction is visible to other
concurrent transactions and data being modified by
other transactions is visible to it.
292. What is transaction manager
Provides the services and management functions
required to support transaction demarcation,
transactional resource management, synchronization,
and transaction context propagation.
293. What is Unicode
A standard defined by the Unicode Consortium that uses
a 16-bit code page that maps digits to characters in
languages around the world. Because 16 bits covers
32,768 codes, Unicode is large enough to include all
the world's languages, with the exception of
ideographic languages that have a different character
for every concept, such as Chinese. For more
information, see http://www.unicode.org/.
294. What is Universal Description, Discovery and
Integration (UDDI) project
An industry initiative to create a
platform-independent, open framework for describing
services, discovering businesses, and integrating
business services using the Internet, as well as a
registry. It is being developed by a vendor
consortium.
295. What is Universal Standard Products and Services
Classification (UNSPSC)
A schema that classifies and identifies commodities.
It is used in sell-side and buy-side catalogs and as a
standardized account code in analyzing expenditure.
296. What is unparsed entity
A general entity that contains something other than
XML. By its nature, an unparsed entity contains binary
data.
296. What is URI
Uniform resource identifier. A globally unique
identifier for an abstract or physical resource. A URL
is a kind of URI that specifies the retrieval protocol
(http or https for Web applications) and physical
location of a resource (host name and host-relative
path). A URN is another type of URI.
297. What is URL
Uniform resource locator. A standard for writing a
textual reference to an arbitrary piece of data in the
World Wide Web. A URL looks like this:
protocol://host/localinfo where protocol specifies a
protocol for fetching the object (such as http or
ftp), host specifies the Internet name of the targeted
host, and localinfo is a string (often a file name)
passed to the protocol handler on the remote host.
298. What is URL path
The part of a URL passed by an HTTP request to invoke
a servlet. A URL path consists of the context path +
servlet path + path info, where Context path is the
path prefix associated with a servlet context of which
the servlet is a part. If this context is the default
context rooted at the base of the Web server's URL
namespace, the path prefix will be an empty string.
Otherwise, the path prefix starts with a / character
but does not end with a / character. Servlet path is
the path section that directly corresponds to the
mapping that activated this request. This path starts
with a / character. Path info is the part of the
request path that is not part of the context path or
the servlet path
299. What is URN
Uniform resource name. A unique identifier that
identifies an entity but doesn't tell where it is
located. A system can use a URN to look up an entity
locally before trying to find it on the Web. It also
allows the Web location to change, while still
allowing the entity to be found.
300. What is user data constraint
Indicates how data between a client and a Web
container should be protected. The protection can be
the prevention of tampering with the data or
prevention of eavesdropping on the data.
J2EE Interview questions and answers
281. What is SQL/J
A set of standards that includes specifications for
embedding SQL statements in methods in the Java
programming language and specifications for calling
Java static methods as SQL stored procedures and
user-defined functions. An SQL checker can detect
errors in static SQL statements at program development
time, rather than at execution time as with a JDBC
driver.
282. What is SSL
Secure Socket Layer. A security protocol that provides
privacy over the Internet. The protocol allows
client-server applications to communicate in a way
that cannot be eavesdropped upon or tampered with.
Servers are always authenticated, and clients are
optionally authenticated.
283. What is stateful session bean
A session bean with a conversational state.
284. What is stateless session bean
A session bean with no conversational state. All
instances of a stateless session bean are identical.
285. What is system administrator
The person responsible for configuring and
administering the enterprise's computers, networks,
and software systems.
286. What is tag
In XML documents, a piece of text that describes a
unit of data or an element. The tag is distinguishable
as markup, as opposed to data, because it is
surrounded by angle brackets (< and >). To treat such
markup syntax as data, you use an entity reference or
a CDATA section.
287. What is template
A set of formatting instructions that apply to the
nodes selected by an XPath _expression.
288. What is tool provider
An organization or software vendor that provides tools
used for the development, packaging, and deployment of
J2EE applications.
289. What is transaction attribute
A value specified in an enterprise bean's deployment
descriptor that is used by the EJB container to
control the transaction scope when the enterprise
bean's methods are invoked. A transaction attribute
can have the following values: Required, RequiresNew,
Supports, NotSupported, Mandatory, or Never.
290. What is transaction
An atomic unit of work that modifies data. A
transaction encloses one or more program statements,
all of which either complete or roll back.
Transactions enable multiple users to access the same
data concurrently.
A set of standards that includes specifications for
embedding SQL statements in methods in the Java
programming language and specifications for calling
Java static methods as SQL stored procedures and
user-defined functions. An SQL checker can detect
errors in static SQL statements at program development
time, rather than at execution time as with a JDBC
driver.
282. What is SSL
Secure Socket Layer. A security protocol that provides
privacy over the Internet. The protocol allows
client-server applications to communicate in a way
that cannot be eavesdropped upon or tampered with.
Servers are always authenticated, and clients are
optionally authenticated.
283. What is stateful session bean
A session bean with a conversational state.
284. What is stateless session bean
A session bean with no conversational state. All
instances of a stateless session bean are identical.
285. What is system administrator
The person responsible for configuring and
administering the enterprise's computers, networks,
and software systems.
286. What is tag
In XML documents, a piece of text that describes a
unit of data or an element. The tag is distinguishable
as markup, as opposed to data, because it is
surrounded by angle brackets (< and >). To treat such
markup syntax as data, you use an entity reference or
a CDATA section.
287. What is template
A set of formatting instructions that apply to the
nodes selected by an XPath _expression.
288. What is tool provider
An organization or software vendor that provides tools
used for the development, packaging, and deployment of
J2EE applications.
289. What is transaction attribute
A value specified in an enterprise bean's deployment
descriptor that is used by the EJB container to
control the transaction scope when the enterprise
bean's methods are invoked. A transaction attribute
can have the following values: Required, RequiresNew,
Supports, NotSupported, Mandatory, or Never.
290. What is transaction
An atomic unit of work that modifies data. A
transaction encloses one or more program statements,
all of which either complete or roll back.
Transactions enable multiple users to access the same
data concurrently.
J2EE Interview questions and answers
271. What is servlet container
A container that provides the network services over
which requests and responses are sent, decodes
requests, and formats responses. All servlet
containers must support HTTP as a protocol for
requests and responses but can also support additional
request-response protocols, such as HTTPS.
272. What is servlet container, distributed
A servlet container that can run a Web application
that is tagged as distributable and that executes
across multiple Java virtual machines running on the
same host or on different hosts.
273. What is servlet context
An object that contains a servlet's view of the Web
application within which the servlet is running. Using
the context, a servlet can log events, obtain URL
references to resources, and set and store attributes
that other servlets in the context can use.
274. What is servlet mapping
Defines an association between a URL pattern and a
servlet. The mapping is used to map requests to
servlets.
275. What is session
An object used by a servlet to track a user's
interaction with a Web application across multiple
HTTP requests.
276. What is session bean
An enterprise bean that is created by a client and
that usually exists only for the duration of a single
client-server session. A session bean performs
operations, such as calculations or database access,
for the client. Although a session bean can be
transactional, it is not recoverable should a system
crash occur. Session bean objects either can be
stateless or can maintain conversational state across
methods and transactions. If a session bean maintains
state, then the EJB container manages this state if
the object must be removed from memory. However, the
session bean object itself must manage its own
persistent data.
277. What is SGML
Standard Generalized Markup Language. The parent of
both HTML and XML. Although HTML shares SGML's
propensity for embedding presentation information in
the markup, XML is a standard that allows information
content to be totally separated from the mechanisms
for rendering that content.
278. What is SOAP
Simple Object Access Protocol. A lightweight protocol
intended for exchanging structured information in a
decentralized, distributed environment. It defines,
using XML technologies, an extensible messaging
framework containing a message construct that can be
exchanged over a variety of underlying protocols.
279. What is SOAP with Attachments API for Java (SAAJ)
The basic package for SOAP messaging, SAAJ contains
the API for creating and populating a SOAP message.
280. What is SQL
Structured Query Language. The standardized relational
database language for defining database objects and
manipulating data.
A container that provides the network services over
which requests and responses are sent, decodes
requests, and formats responses. All servlet
containers must support HTTP as a protocol for
requests and responses but can also support additional
request-response protocols, such as HTTPS.
272. What is servlet container, distributed
A servlet container that can run a Web application
that is tagged as distributable and that executes
across multiple Java virtual machines running on the
same host or on different hosts.
273. What is servlet context
An object that contains a servlet's view of the Web
application within which the servlet is running. Using
the context, a servlet can log events, obtain URL
references to resources, and set and store attributes
that other servlets in the context can use.
274. What is servlet mapping
Defines an association between a URL pattern and a
servlet. The mapping is used to map requests to
servlets.
275. What is session
An object used by a servlet to track a user's
interaction with a Web application across multiple
HTTP requests.
276. What is session bean
An enterprise bean that is created by a client and
that usually exists only for the duration of a single
client-server session. A session bean performs
operations, such as calculations or database access,
for the client. Although a session bean can be
transactional, it is not recoverable should a system
crash occur. Session bean objects either can be
stateless or can maintain conversational state across
methods and transactions. If a session bean maintains
state, then the EJB container manages this state if
the object must be removed from memory. However, the
session bean object itself must manage its own
persistent data.
277. What is SGML
Standard Generalized Markup Language. The parent of
both HTML and XML. Although HTML shares SGML's
propensity for embedding presentation information in
the markup, XML is a standard that allows information
content to be totally separated from the mechanisms
for rendering that content.
278. What is SOAP
Simple Object Access Protocol. A lightweight protocol
intended for exchanging structured information in a
decentralized, distributed environment. It defines,
using XML technologies, an extensible messaging
framework containing a message construct that can be
exchanged over a variety of underlying protocols.
279. What is SOAP with Attachments API for Java (SAAJ)
The basic package for SOAP messaging, SAAJ contains
the API for creating and populating a SOAP message.
280. What is SQL
Structured Query Language. The standardized relational
database language for defining database objects and
manipulating data.
J2EE Interview questions and answers
261. What is role mapping
The process of associating the groups or principals
(or both), recognized by the container with security
roles specified in the deployment descriptor. Security
roles must be mapped by the deployer before a
component is installed in the server.
262. What is role (security)
An abstract logical grouping of users that is defined
by the application assembler. When an application is
deployed, the roles are mapped to security identities,
such as principals or groups, in the operational
environment. In the J2EE server authentication
service, a role is an abstract name for permission to
access a particular set of resources. A role can be
compared to a key that can open a lock. Many people
might have a copy of the key; the lock doesn't care
who you are, only that you have the right key.
263. What is rollback
The point in a transaction when all updates to any
resources involved in the transaction are reversed.
264. What is root
The outermost element in an XML document. The element
that contains all other elements.
265. What is SAX
Abbreviation of Simple API for XML.
266. What is Simple API for XML
An event-driven interface in which the parser invokes
one of several methods supplied by the caller when a
parsing event occurs. Events include recognizing an
XML tag, finding an error, encountering a reference to
an external entity, or processing a DTD specification.
267. What is schema
A database-inspired method for specifying constraints
on XML documents using an XML-based language. Schemas
address deficiencies in DTDs, such as the inability to
put constraints on the kinds of data that can occur in
a particular field. Because schemas are founded on
XML, they are hierarchical. Thus it is easier to
create an unambiguous specification, and it is
possible to determine the scope over which a comment
is meant to apply.
268. What is Secure Socket Layer (SSL)
A technology that allows Web browsers and Web servers
to communicate over a secured connection.
267. What is security attributes
A set of properties associated with a principal.
Security attributes can be associated with a principal
by an authentication protocol or by a J2EE product
provider or both.
268. What is security constraint
A declarative way to annotate the intended protection
of Web content. A security constraint consists of a
Web resource collection, an authorization constraint,
and a user data constraint.
269. What is security context
An object that encapsulates the shared state
information regarding security between two entities.
270. What is security permission
A mechanism defined by J2SE, and used by the J2EE
platform to express the programming restrictions
imposed on application component developers.
The process of associating the groups or principals
(or both), recognized by the container with security
roles specified in the deployment descriptor. Security
roles must be mapped by the deployer before a
component is installed in the server.
262. What is role (security)
An abstract logical grouping of users that is defined
by the application assembler. When an application is
deployed, the roles are mapped to security identities,
such as principals or groups, in the operational
environment. In the J2EE server authentication
service, a role is an abstract name for permission to
access a particular set of resources. A role can be
compared to a key that can open a lock. Many people
might have a copy of the key; the lock doesn't care
who you are, only that you have the right key.
263. What is rollback
The point in a transaction when all updates to any
resources involved in the transaction are reversed.
264. What is root
The outermost element in an XML document. The element
that contains all other elements.
265. What is SAX
Abbreviation of Simple API for XML.
266. What is Simple API for XML
An event-driven interface in which the parser invokes
one of several methods supplied by the caller when a
parsing event occurs. Events include recognizing an
XML tag, finding an error, encountering a reference to
an external entity, or processing a DTD specification.
267. What is schema
A database-inspired method for specifying constraints
on XML documents using an XML-based language. Schemas
address deficiencies in DTDs, such as the inability to
put constraints on the kinds of data that can occur in
a particular field. Because schemas are founded on
XML, they are hierarchical. Thus it is easier to
create an unambiguous specification, and it is
possible to determine the scope over which a comment
is meant to apply.
268. What is Secure Socket Layer (SSL)
A technology that allows Web browsers and Web servers
to communicate over a secured connection.
267. What is security attributes
A set of properties associated with a principal.
Security attributes can be associated with a principal
by an authentication protocol or by a J2EE product
provider or both.
268. What is security constraint
A declarative way to annotate the intended protection
of Web content. A security constraint consists of a
Web resource collection, an authorization constraint,
and a user data constraint.
269. What is security context
An object that encapsulates the shared state
information regarding security between two entities.
270. What is security permission
A mechanism defined by J2SE, and used by the J2EE
platform to express the programming restrictions
imposed on application component developers.
J2EE Interview questions and answers
251. What is renderer
A Java class that can render the output for a set of
JavaServer Faces UI components.
252. What is request-response messaging
A method of messaging that includes blocking until a
response is received.
253. What is resource adapter
A system-level software driver that is used by an EJB
container or an application client to connect to an
enterprise information system. A resource adapter
typically is specific to an enterprise information
system. It is available as a library and is used
within the address space of the server or client using
it. A resource adapter plugs in to a container. The
application components deployed on the container then
use the client API (exposed by the adapter) or
tool-generated high-level abstractions to access the
underlying enterprise information system. The resource
adapter and EJB container collaborate to provide the
underlying mechanisms-transactions, security, and
connection pooling-for connectivity to the enterprise
information system.
254. What is resource adapter module
A deployable unit that contains all Java interfaces,
classes, and native libraries, implementing a resource
adapter along with the resource adapter deployment
descriptor.
255. What is resource manager
Provides access to a set of shared resources. A
resource manager participates in transactions that are
externally controlled and coordinated by a transaction
manager. A resource manager typically is in a
different address space or on a different machine from
the clients that access it. Note: An enterprise
information system is referred to as a resource
manager when it is mentioned in the context of
resource and transaction management.
256. What is resource manager connection
An object that represents a session with a resource
manager.
257. What is resource manager connection factory
An object used for creating a resource manager
connection.
258. What is RMI
Remote Method Invocation. A technology that allows an
object running in one Java virtual machine to invoke
methods on an object running in a different Java
virtual machine.
259. What is RMI-IIOP
A version of RMI implemented to use the CORBA IIOP
protocol. RMI over IIOP provides interoperability with
CORBA objects implemented in any language if all the
remote interfaces are originally defined as RMI
interfaces.
260. What is role (development)
The function performed by a party in the development
and deployment phases of an application developed
using J2EE technology. The roles are application
component provider, application assembler, deployer,
J2EE product provider, EJB container provider, EJB
server provider, Web container provider, Web server
provider, tool provider, and system administrator.
A Java class that can render the output for a set of
JavaServer Faces UI components.
252. What is request-response messaging
A method of messaging that includes blocking until a
response is received.
253. What is resource adapter
A system-level software driver that is used by an EJB
container or an application client to connect to an
enterprise information system. A resource adapter
typically is specific to an enterprise information
system. It is available as a library and is used
within the address space of the server or client using
it. A resource adapter plugs in to a container. The
application components deployed on the container then
use the client API (exposed by the adapter) or
tool-generated high-level abstractions to access the
underlying enterprise information system. The resource
adapter and EJB container collaborate to provide the
underlying mechanisms-transactions, security, and
connection pooling-for connectivity to the enterprise
information system.
254. What is resource adapter module
A deployable unit that contains all Java interfaces,
classes, and native libraries, implementing a resource
adapter along with the resource adapter deployment
descriptor.
255. What is resource manager
Provides access to a set of shared resources. A
resource manager participates in transactions that are
externally controlled and coordinated by a transaction
manager. A resource manager typically is in a
different address space or on a different machine from
the clients that access it. Note: An enterprise
information system is referred to as a resource
manager when it is mentioned in the context of
resource and transaction management.
256. What is resource manager connection
An object that represents a session with a resource
manager.
257. What is resource manager connection factory
An object used for creating a resource manager
connection.
258. What is RMI
Remote Method Invocation. A technology that allows an
object running in one Java virtual machine to invoke
methods on an object running in a different Java
virtual machine.
259. What is RMI-IIOP
A version of RMI implemented to use the CORBA IIOP
protocol. RMI over IIOP provides interoperability with
CORBA objects implemented in any language if all the
remote interfaces are originally defined as RMI
interfaces.
260. What is role (development)
The function performed by a party in the development
and deployment phases of an application developed
using J2EE technology. The roles are application
component provider, application assembler, deployer,
J2EE product provider, EJB container provider, EJB
server provider, Web container provider, Web server
provider, tool provider, and system administrator.
J2EE Interview questions and answers
241. What is RDF schema
A standard for specifying consistency rules that apply
to the specifications contained in an RDF.
242. What is realm
See security policy domain. Also, a string, passed as
part of an HTTP request during basic authentication,
that defines a protection space. The protected
resources on a server can be partitioned into a set of
protection spaces, each with its own authentication
scheme or authorization database or both. In the J2EE
server authentication service, a realm is a complete
database of roles, users, and groups that identify
valid users of a Web application or a set of Web
applications.
243. What is reentrant entity bean
An entity bean that can handle multiple simultaneous,
interleaved, or nested invocations that will not
interfere with each other.
244. What is reference
A reference to an entity that is substituted for the
reference when the XML document is parsed. It can
reference a predefined entity such as < or reference
one that is defined in the DTD. In the XML data, the
reference could be to an entity that is defined in the
local subset of the DTD or to an external XML file (an
external entity). The DTD can also carve out a segment
of DTD specifications and give it a name so that it
can be reused (included) at multiple points in the DTD
by defining a parameter entity.
245. What is registry
An infrastructure that enables the building,
deployment, and discovery of Web services. It is a
neutral third party that facilitates dynamic and
loosely coupled business-to-business (B2B)
interactions.
246. What is registry provider
An implementation of a business registry that conforms
to a specification for XML registries (for example,
ebXML or UDDI).
247. What is relationship field
A virtual field of an entity bean having
container-managed persistence; it identifies a related
entity bean.
248. What is remote interface
One of two interfaces for an enterprise bean. The
remote interface defines the business methods callable
by a client.
249. What is remove method
Method defined in the home interface and invoked by a
client to destroy an enterprise bean.
250. What is render kit
A set of renderers that render output to a particular
client. The JavaServer Faces implementation provides a
standard HTML render kit, which is composed of
renderers that can render HMTL markup.
A standard for specifying consistency rules that apply
to the specifications contained in an RDF.
242. What is realm
See security policy domain. Also, a string, passed as
part of an HTTP request during basic authentication,
that defines a protection space. The protected
resources on a server can be partitioned into a set of
protection spaces, each with its own authentication
scheme or authorization database or both. In the J2EE
server authentication service, a realm is a complete
database of roles, users, and groups that identify
valid users of a Web application or a set of Web
applications.
243. What is reentrant entity bean
An entity bean that can handle multiple simultaneous,
interleaved, or nested invocations that will not
interfere with each other.
244. What is reference
A reference to an entity that is substituted for the
reference when the XML document is parsed. It can
reference a predefined entity such as < or reference
one that is defined in the DTD. In the XML data, the
reference could be to an entity that is defined in the
local subset of the DTD or to an external XML file (an
external entity). The DTD can also carve out a segment
of DTD specifications and give it a name so that it
can be reused (included) at multiple points in the DTD
by defining a parameter entity.
245. What is registry
An infrastructure that enables the building,
deployment, and discovery of Web services. It is a
neutral third party that facilitates dynamic and
loosely coupled business-to-business (B2B)
interactions.
246. What is registry provider
An implementation of a business registry that conforms
to a specification for XML registries (for example,
ebXML or UDDI).
247. What is relationship field
A virtual field of an entity bean having
container-managed persistence; it identifies a related
entity bean.
248. What is remote interface
One of two interfaces for an enterprise bean. The
remote interface defines the business methods callable
by a client.
249. What is remove method
Method defined in the home interface and invoked by a
client to destroy an enterprise bean.
250. What is render kit
A set of renderers that render output to a particular
client. The JavaServer Faces implementation provides a
standard HTML render kit, which is composed of
renderers that can render HMTL markup.
J2EE Interview questions and answers
231. What is privilege
A security attribute that does not have the property
of uniqueness and that can be shared by many
principals.
232. What is processing instruction
Information contained in an XML structure that is
intended to be interpreted by a specific application.
233. What is programmatic security
Security decisions that are made by security-aware
applications. Programmatic security is useful when
declarative security alone is not sufficient to
express the security model of an application.
234. What is prolog
The part of an XML document that precedes the XML
data. The prolog includes the declaration and an
optional DTD.
235. What is public key certificate
Used in client-certificate authentication to enable
the server, and optionally the client, to authenticate
each other. The public key certificate is the digital
equivalent of a passport. It is issued by a trusted
organization, called a certificate authority, and
provides identification for the bearer.
236. What is publish/subscribe messaging system
A messaging system in which clients address messages
to a specific node in a content hierarchy, called a
topic. Publishers and subscribers are generally
anonymous and can dynamically publish or subscribe to
the content hierarchy. The system takes care of
distributing the messages arriving from a node's
multiple publishers to its multiple subscribers.
237. What is query string
A component of an HTTP request URL that contains a set
of parameters and values that affect the handling of
the request.
238. What is queue
A messaging system built on the concept of message
queues. Each message is addressed to a specific queue;
clients extract messages from the queues established
to hold their messages.
239. What is RAR
Resource Adapter Archive. A JAR archive that contains
a resource adapter module.
240. What is RDF
Resource Description Framework. A standard for
defining the kind of data that an XML file contains.
Such information can help ensure semantic
integrity-for example-by helping to make sure that a
date is treated as a date rather than simply as text.
A security attribute that does not have the property
of uniqueness and that can be shared by many
principals.
232. What is processing instruction
Information contained in an XML structure that is
intended to be interpreted by a specific application.
233. What is programmatic security
Security decisions that are made by security-aware
applications. Programmatic security is useful when
declarative security alone is not sufficient to
express the security model of an application.
234. What is prolog
The part of an XML document that precedes the XML
data. The prolog includes the declaration and an
optional DTD.
235. What is public key certificate
Used in client-certificate authentication to enable
the server, and optionally the client, to authenticate
each other. The public key certificate is the digital
equivalent of a passport. It is issued by a trusted
organization, called a certificate authority, and
provides identification for the bearer.
236. What is publish/subscribe messaging system
A messaging system in which clients address messages
to a specific node in a content hierarchy, called a
topic. Publishers and subscribers are generally
anonymous and can dynamically publish or subscribe to
the content hierarchy. The system takes care of
distributing the messages arriving from a node's
multiple publishers to its multiple subscribers.
237. What is query string
A component of an HTTP request URL that contains a set
of parameters and values that affect the handling of
the request.
238. What is queue
A messaging system built on the concept of message
queues. Each message is addressed to a specific queue;
clients extract messages from the queues established
to hold their messages.
239. What is RAR
Resource Adapter Archive. A JAR archive that contains
a resource adapter module.
240. What is RDF
Resource Description Framework. A standard for
defining the kind of data that an XML file contains.
Such information can help ensure semantic
integrity-for example-by helping to make sure that a
date is treated as a date rather than simply as text.
J2EE Interview questions and answers
201. What is normalization
The process of removing redundancy by modularizing, as
with subroutines, and of removing superfluous
differences by reducing them to a common denominator.
For example, line endings from different systems are
normalized by reducing them to a single new line, and
multiple whitespace characters are normalized to one
space.
202. What is North American Industry Classification
System (NAICS)
A system for classifying business establishments based
on the processes they use to produce goods or
services.
203. What is notation
A mechanism for defining a data format for a non-XML
document referenced as an unparsed entity. This is a
holdover from SGML. A newer standard is to use MIME
data types and namespaces to prevent naming conflicts.
204. What is OASIS
Organization for the Advancement of Structured
Information Standards. A consortium that drives the
development, convergence, and adoption of e-business
standards.
205. What is OMG
Object Management Group. A consortium that produces
and maintains computer industry specifications for
interoperable enterprise applications.
206. What is one-way messaging
A method of transmitting messages without having to
block until a response is received.
207. What is ORB
Object request broker. A library that enables CORBA
objects to locate and communicate with one another.
208. What is OS principal
A principal native to the operating system on which
the J2EE platform is executing.
209. What is OTS
Object Transaction Service. A definition of the
interfaces that permit CORBA objects to participate in
transactions.
The process of removing redundancy by modularizing, as
with subroutines, and of removing superfluous
differences by reducing them to a common denominator.
For example, line endings from different systems are
normalized by reducing them to a single new line, and
multiple whitespace characters are normalized to one
space.
202. What is North American Industry Classification
System (NAICS)
A system for classifying business establishments based
on the processes they use to produce goods or
services.
203. What is notation
A mechanism for defining a data format for a non-XML
document referenced as an unparsed entity. This is a
holdover from SGML. A newer standard is to use MIME
data types and namespaces to prevent naming conflicts.
204. What is OASIS
Organization for the Advancement of Structured
Information Standards. A consortium that drives the
development, convergence, and adoption of e-business
standards.
205. What is OMG
Object Management Group. A consortium that produces
and maintains computer industry specifications for
interoperable enterprise applications.
206. What is one-way messaging
A method of transmitting messages without having to
block until a response is received.
207. What is ORB
Object request broker. A library that enables CORBA
objects to locate and communicate with one another.
208. What is OS principal
A principal native to the operating system on which
the J2EE platform is executing.
209. What is OTS
Object Transaction Service. A definition of the
interfaces that permit CORBA objects to participate in
transactions.
J2EE Interview questions and answers
191. What is message consumer
An object created by a JMS session that is used for
receiving messages sent to a destination.
192. What is message-driven bean
An enterprise bean that is an asynchronous message
consumer. A message-driven bean has no state for a
specific client, but its instance variables can
contain state across the handling of client messages,
including an open database connection and an object
reference to an EJB object. A client accesses a
message-driven bean by sending messages to the
destination for which the bean is a message listener.
193. What is message producer
An object created by a JMS session that is used for
sending messages to a destination.
194. What is mixed-content model
A DTD specification that defines an element as
containing a mixture of text and one more other
elements. The specification must start with #PCDATA,
followed by diverse elements, and must end with the
"zero-or-more" asterisk symbol (*).
195. What is method-binding _expression
A JavaServer Faces EL _expression that refers to a
method of a backing bean. This method performs either
event handling, validation, or navigation processing
for the UI component whose tag uses the method-binding
_expression.
196. What is method permission
An authorization rule that determines who is permitted
to execute one or more enterprise bean methods.
197. What is mutual authentication
An authentication mechanism employed by two parties
for the purpose of proving each other's identity to
one another.
198. What is namespace
A standard that lets you specify a unique label for
the set of element names defined by a DTD. A document
using that DTD can be included in any other document
without having a conflict between element names. The
elements defined in your DTD are then uniquely
identified so that, for example, the parser can tell
when an element should be interpreted according to
your DTD rather than using the definition for an
element in a different DTD.
199. What is naming context
A set of associations between unique, atomic,
people-friendly identifiers and objects.
200. What is naming environment
A mechanism that allows a component to be customized
without the need to access or change the component's
source code. A container implements the component's
naming environment and provides it to the component as
a JNDI naming context. Each component names and
accesses its environment entries using the
java:comp/env JNDI context. The environment entries
are declaratively specified in the component's
deployment descriptor.
An object created by a JMS session that is used for
receiving messages sent to a destination.
192. What is message-driven bean
An enterprise bean that is an asynchronous message
consumer. A message-driven bean has no state for a
specific client, but its instance variables can
contain state across the handling of client messages,
including an open database connection and an object
reference to an EJB object. A client accesses a
message-driven bean by sending messages to the
destination for which the bean is a message listener.
193. What is message producer
An object created by a JMS session that is used for
sending messages to a destination.
194. What is mixed-content model
A DTD specification that defines an element as
containing a mixture of text and one more other
elements. The specification must start with #PCDATA,
followed by diverse elements, and must end with the
"zero-or-more" asterisk symbol (*).
195. What is method-binding _expression
A JavaServer Faces EL _expression that refers to a
method of a backing bean. This method performs either
event handling, validation, or navigation processing
for the UI component whose tag uses the method-binding
_expression.
196. What is method permission
An authorization rule that determines who is permitted
to execute one or more enterprise bean methods.
197. What is mutual authentication
An authentication mechanism employed by two parties
for the purpose of proving each other's identity to
one another.
198. What is namespace
A standard that lets you specify a unique label for
the set of element names defined by a DTD. A document
using that DTD can be included in any other document
without having a conflict between element names. The
elements defined in your DTD are then uniquely
identified so that, for example, the parser can tell
when an element should be interpreted according to
your DTD rather than using the definition for an
element in a different DTD.
199. What is naming context
A set of associations between unique, atomic,
people-friendly identifiers and objects.
200. What is naming environment
A mechanism that allows a component to be customized
without the need to access or change the component's
source code. A container implements the component's
naming environment and provides it to the component as
a JNDI naming context. Each component names and
accesses its environment entries using the
java:comp/env JNDI context. The environment entries
are declaratively specified in the component's
deployment descriptor.
J2EE Interview questions and answers
181. What is JSP tag library
A collection of custom tags described via a tag
library descriptor and Java classes.
182. What is JSTL
Abbreviate of JavaServer Pages Standard Tag Library.
183. What is JTA
Abbreviate of Java Transaction API.
184. What is JTS
Abbreviate of Java Transaction Service.
185. What is keystore
A file containing the keys and certificates used for
authentication
186. What is life cycle (J2EE component)
The framework events of a J2EE component's existence.
Each type of component has defining events that mark
its transition into states in which it has varying
availability for use. For example, a servlet is
created and has its init method called by its
container before invocation of its service method by
clients or other servlets that require its
functionality. After the call of its init method, it
has the data and readiness for its intended use. The
servlet's destroy method is called by its container
before the ending of its existence so that processing
associated with winding up can be done and resources
can be released. The init and destroy methods in this
example are callback methods. Similar considerations
apply to the life cycle of all J2EE component types:
enterprise beans, Web components (servlets or JSP
pages), applets, and application clients.
187. What is life cycle (JavaServer Faces)
A set of phases during which a request for a page is
received, a UI component tree representing the page is
processed, and a response is produced. During the
phases of the life cycle: The local data of the
components is updated with the values contained in the
request parameters. Events generated by the components
are processed. Validators and converters registered on
the components are processed. The components' local
data is updated to back-end objects. The response is
rendered to the client while the component state of
the response is saved on the server for future
requests.
188. What is local subset
That part of the DTD that is defined within the
current XML file.
189. What is managed bean creation facility
A mechanism for defining the characteristics of
JavaBeans components used in a JavaServer Faces
application.
190. What is message
In the Java Message Service, an asynchronous request,
report, or event that is created, sent, and consumed
by an enterprise application and not by a human. It
contains vital information needed to coordinate
enterprise applications, in the form of precisely
formatted data that describes specific business
actions.
A collection of custom tags described via a tag
library descriptor and Java classes.
182. What is JSTL
Abbreviate of JavaServer Pages Standard Tag Library.
183. What is JTA
Abbreviate of Java Transaction API.
184. What is JTS
Abbreviate of Java Transaction Service.
185. What is keystore
A file containing the keys and certificates used for
authentication
186. What is life cycle (J2EE component)
The framework events of a J2EE component's existence.
Each type of component has defining events that mark
its transition into states in which it has varying
availability for use. For example, a servlet is
created and has its init method called by its
container before invocation of its service method by
clients or other servlets that require its
functionality. After the call of its init method, it
has the data and readiness for its intended use. The
servlet's destroy method is called by its container
before the ending of its existence so that processing
associated with winding up can be done and resources
can be released. The init and destroy methods in this
example are callback methods. Similar considerations
apply to the life cycle of all J2EE component types:
enterprise beans, Web components (servlets or JSP
pages), applets, and application clients.
187. What is life cycle (JavaServer Faces)
A set of phases during which a request for a page is
received, a UI component tree representing the page is
processed, and a response is produced. During the
phases of the life cycle: The local data of the
components is updated with the values contained in the
request parameters. Events generated by the components
are processed. Validators and converters registered on
the components are processed. The components' local
data is updated to back-end objects. The response is
rendered to the client while the component state of
the response is saved on the server for future
requests.
188. What is local subset
That part of the DTD that is defined within the
current XML file.
189. What is managed bean creation facility
A mechanism for defining the characteristics of
JavaBeans components used in a JavaServer Faces
application.
190. What is message
In the Java Message Service, an asynchronous request,
report, or event that is created, sent, and consumed
by an enterprise application and not by a human. It
contains vital information needed to coordinate
enterprise applications, in the form of precisely
formatted data that describes specific business
actions.
J2EE Interview questions and answers
171. What is JSP document
A JSP page written in XML syntax and subject to the
constraints of XML documents.
172. What is JSP element
A portion of a JSP page that is recognized by a JSP
translator. An element can be a directive, an action,
or a scripting element.
173. What is JSP _expression
A scripting element that contains a valid scripting
language _expression that is evaluated, converted to a
String, and placed into the implicit out object.
174. What is JSP _expression language
A language used to write expressions that access the
properties of JavaBeans components. EL expressions can
be used in static text and in any standard or custom
tag attribute that can accept an _expression.
175. What is JSP page
A text-based document containing static text and JSP
elements that describes how to process a request to
create a response. A JSP page is translated into and
handles requests as a servlet.
176. What is JSP scripting element
A JSP declaration, scriptlet, or _expression whose
syntax is defined by the JSP specification and whose
content is written according to the scripting language
used in the JSP page. The JSP specification describes
the syntax and semantics for the case where the
language page attribute is "java".
177. What is JSP scriptlet
A JSP scripting element containing any code fragment
that is valid in the scripting language used in the
JSP page. The JSP specification describes what is a
valid scriptlet for the case where the language page
attribute is "java".
178. What is JSP standard action
An action that is defined in the JSP specification and
is always available to a JSP page.
179. What is JSP tag file
A source file containing a reusable fragment of JSP
code that is translated into a tag handler when a JSP
page is translated into a servlet.
180. What is JSP tag handler
A Java programming language object that implements the
behavior of a custom tag.
A JSP page written in XML syntax and subject to the
constraints of XML documents.
172. What is JSP element
A portion of a JSP page that is recognized by a JSP
translator. An element can be a directive, an action,
or a scripting element.
173. What is JSP _expression
A scripting element that contains a valid scripting
language _expression that is evaluated, converted to a
String, and placed into the implicit out object.
174. What is JSP _expression language
A language used to write expressions that access the
properties of JavaBeans components. EL expressions can
be used in static text and in any standard or custom
tag attribute that can accept an _expression.
175. What is JSP page
A text-based document containing static text and JSP
elements that describes how to process a request to
create a response. A JSP page is translated into and
handles requests as a servlet.
176. What is JSP scripting element
A JSP declaration, scriptlet, or _expression whose
syntax is defined by the JSP specification and whose
content is written according to the scripting language
used in the JSP page. The JSP specification describes
the syntax and semantics for the case where the
language page attribute is "java".
177. What is JSP scriptlet
A JSP scripting element containing any code fragment
that is valid in the scripting language used in the
JSP page. The JSP specification describes what is a
valid scriptlet for the case where the language page
attribute is "java".
178. What is JSP standard action
An action that is defined in the JSP specification and
is always available to a JSP page.
179. What is JSP tag file
A source file containing a reusable fragment of JSP
code that is translated into a tag handler when a JSP
page is translated into a servlet.
180. What is JSP tag handler
A Java programming language object that implements the
behavior of a custom tag.
J2EE Interview questions and answers
161. What is JNDI
Abbreviate of Java Naming and Directory Interface.
162. What is JSP
Abbreviate of JavaServer Pages.
163. What is JSP action
A JSP element that can act on implicit objects and
other server-side objects or can define new scripting
variables. Actions follow the XML syntax for elements,
with a start tag, a body, and an end tag; if the body
is empty it can also use the empty tag syntax. The tag
must use a prefix. There are standard and custom
actions.
164. What is JSP container
A container that provides the same services as a
servlet container and an engine that interprets and
processes JSP pages into a servlet.
165. What is JSP container, distributed
A JSP container that can run a Web application that is
tagged as distributable and is spread across multiple
Java virtual machines that might be running on
different hosts.
167. What is JSP custom action
A user-defined action described in a portable manner
by a tag library descriptor and imported into a JSP
page by a taglib directive. Custom actions are used to
encapsulate recurring tasks in writing JSP pages.
168. What is JSP custom tag
A tag that references a JSP custom action.
169. What is JSP declaration
A JSP scripting element that declares methods,
variables, or both in a JSP page.
170. What is JSP directive
A JSP element that gives an instruction to the JSP
container and is interpreted at translation time.
Abbreviate of Java Naming and Directory Interface.
162. What is JSP
Abbreviate of JavaServer Pages.
163. What is JSP action
A JSP element that can act on implicit objects and
other server-side objects or can define new scripting
variables. Actions follow the XML syntax for elements,
with a start tag, a body, and an end tag; if the body
is empty it can also use the empty tag syntax. The tag
must use a prefix. There are standard and custom
actions.
164. What is JSP container
A container that provides the same services as a
servlet container and an engine that interprets and
processes JSP pages into a servlet.
165. What is JSP container, distributed
A JSP container that can run a Web application that is
tagged as distributable and is spread across multiple
Java virtual machines that might be running on
different hosts.
167. What is JSP custom action
A user-defined action described in a portable manner
by a tag library descriptor and imported into a JSP
page by a taglib directive. Custom actions are used to
encapsulate recurring tasks in writing JSP pages.
168. What is JSP custom tag
A tag that references a JSP custom action.
169. What is JSP declaration
A JSP scripting element that declares methods,
variables, or both in a JSP page.
170. What is JSP directive
A JSP element that gives an instruction to the JSP
container and is interpreted at translation time.
J2EE Interview questions and answers
151. What is JavaServer Pages Standard Tag Library
(JSTL)
A tag library that encapsulates core functionality
common to many JSP applications. JSTL has support for
common, structural tasks such as iteration and
conditionals, tags for manipulating XML documents,
internationalization and locale-specific formatting
tags, SQL tags, and functions.
152. What is JAXR client
A client program that uses the JAXR API to access a
business registry via a JAXR provider.
153. What is JAXR provider
An implementation of the JAXR API that provides access
to a specific registry provider or to a class of
registry providers that are based on a common
specification.
154. What is JDBC
An JDBC for database-independent connectivity between
the J2EE platform and a wide range of data sources.
155. What is JMS
Java Message Service.
156. What is JMS administered object
A preconfigured JMS object (a resource manager
connection factory or a destination) created by an
administrator for the use of JMS clients and placed in
a JNDI namespace
157. What is JMS application
One or more JMS clients that exchange messages.
158. What is JMS client
A Java language program that sends or receives
messages.
159. What is JMS provider
A messaging system that implements the Java Message
Service as well as other administrative and control
functionality needed in a full-featured messaging
product.
160. What is JMS session
A single-threaded context for sending and receiving
JMS messages. A JMS session can be nontransacted,
locally transacted, or participating in a distributed
transaction.
(JSTL)
A tag library that encapsulates core functionality
common to many JSP applications. JSTL has support for
common, structural tasks such as iteration and
conditionals, tags for manipulating XML documents,
internationalization and locale-specific formatting
tags, SQL tags, and functions.
152. What is JAXR client
A client program that uses the JAXR API to access a
business registry via a JAXR provider.
153. What is JAXR provider
An implementation of the JAXR API that provides access
to a specific registry provider or to a class of
registry providers that are based on a common
specification.
154. What is JDBC
An JDBC for database-independent connectivity between
the J2EE platform and a wide range of data sources.
155. What is JMS
Java Message Service.
156. What is JMS administered object
A preconfigured JMS object (a resource manager
connection factory or a destination) created by an
administrator for the use of JMS clients and placed in
a JNDI namespace
157. What is JMS application
One or more JMS clients that exchange messages.
158. What is JMS client
A Java language program that sends or receives
messages.
159. What is JMS provider
A messaging system that implements the Java Message
Service as well as other administrative and control
functionality needed in a full-featured messaging
product.
160. What is JMS session
A single-threaded context for sending and receiving
JMS messages. A JMS session can be nontransacted,
locally transacted, or participating in a distributed
transaction.
J2EE Interview questions and answers
141. What is JavaServer Faces Technology
A framework for building server-side user interfaces
for Web applications written in the Java programming
language.
142. What is JavaServer Faces conversion model
A mechanism for converting between string-based markup
generated by JavaServer Faces UI components and
server-side Java objects.
143. What is JavaServer Faces event and listener model
A mechanism for determining how events emitted by
JavaServer Faces UI components are handled. This model
is based on the JavaBeans component event and listener
model.
144. What is JavaServer Faces _expression language
A simple _expression language used by a JavaServer
Faces UI component tag attributes to bind the
associated component to a bean property or to bind the
associated component's value to a method or an
external data source, such as a bean property. Unlike
JSP EL expressions, JavaServer Faces EL expressions
are evaluated by the JavaServer Faces implementation
rather than by the Web container.
145. What is JavaServer Faces navigation model
A mechanism for defining the sequence in which pages
in a JavaServer Faces application are displayed.
147. What is JavaServer Faces UI component
A user interface control that outputs data to a client
or allows a user to input data to a JavaServer Faces
application.
148. What is JavaServer Faces UI component class
A JavaServer Faces class that defines the behavior and
properties of a JavaServer Faces UI component.
149. What is JavaServer Faces validation model
A mechanism for validating the data a user inputs to a
JavaServer Faces UI component.
150. What is JavaServer Pages (JSP)
An extensible Web technology that uses static data,
JSP elements, and server-side Java objects to generate
dynamic content for a client. Typically the static
data is HTML or XML elements, and in many cases the
client is a Web browser.
A framework for building server-side user interfaces
for Web applications written in the Java programming
language.
142. What is JavaServer Faces conversion model
A mechanism for converting between string-based markup
generated by JavaServer Faces UI components and
server-side Java objects.
143. What is JavaServer Faces event and listener model
A mechanism for determining how events emitted by
JavaServer Faces UI components are handled. This model
is based on the JavaBeans component event and listener
model.
144. What is JavaServer Faces _expression language
A simple _expression language used by a JavaServer
Faces UI component tag attributes to bind the
associated component to a bean property or to bind the
associated component's value to a method or an
external data source, such as a bean property. Unlike
JSP EL expressions, JavaServer Faces EL expressions
are evaluated by the JavaServer Faces implementation
rather than by the Web container.
145. What is JavaServer Faces navigation model
A mechanism for defining the sequence in which pages
in a JavaServer Faces application are displayed.
147. What is JavaServer Faces UI component
A user interface control that outputs data to a client
or allows a user to input data to a JavaServer Faces
application.
148. What is JavaServer Faces UI component class
A JavaServer Faces class that defines the behavior and
properties of a JavaServer Faces UI component.
149. What is JavaServer Faces validation model
A mechanism for validating the data a user inputs to a
JavaServer Faces UI component.
150. What is JavaServer Pages (JSP)
An extensible Web technology that uses static data,
JSP elements, and server-side Java objects to generate
dynamic content for a client. Typically the static
data is HTML or XML elements, and in many cases the
client is a Web browser.
J2EE Interview questions and answers
131. What is Java API for XML Registries (JAXR)
An API for accessing various kinds of XML registries.
132. What is Java API for XML-based RPC (JAX-RPC)
An API for building Web services and clients that use
remote procedure calls and XML
133. What is Java IDL
A technology that provides CORBA interoperability and
connectivity capabilities for the J2EE platform. These
capabilities enable J2EE applications to invoke
operations on remote network services using the Object
Management Group IDL and IIOP.
134. What is Java Message Service (JMS)
An API for invoking operations on enterprise messaging
systems.
135. What is Java Naming and Directory Interface
(JNDI)
An API that provides naming and directory
functionality.
136. What is Java Secure Socket Extension (JSSE)
A set of packages that enable secure Internet
communications.
137. What is Java Transaction API (JTA)
An API that allows applications and J2EE servers to
access transactions.
138. What is Java Transaction Service (JTS)
Specifies the implementation of a transaction manager
that supports JTA and implements the Java mapping of
the Object Management Group Object Transaction Service
1.1 specification at the level below the API.
139. What is JavaBeans component
A Java class that can be manipulated by tools and
composed into applications. A JavaBeans component must
adhere to certain property and event interface
conventions.
140. What is JavaMail
An API for sending and receiving email.
An API for accessing various kinds of XML registries.
132. What is Java API for XML-based RPC (JAX-RPC)
An API for building Web services and clients that use
remote procedure calls and XML
133. What is Java IDL
A technology that provides CORBA interoperability and
connectivity capabilities for the J2EE platform. These
capabilities enable J2EE applications to invoke
operations on remote network services using the Object
Management Group IDL and IIOP.
134. What is Java Message Service (JMS)
An API for invoking operations on enterprise messaging
systems.
135. What is Java Naming and Directory Interface
(JNDI)
An API that provides naming and directory
functionality.
136. What is Java Secure Socket Extension (JSSE)
A set of packages that enable secure Internet
communications.
137. What is Java Transaction API (JTA)
An API that allows applications and J2EE servers to
access transactions.
138. What is Java Transaction Service (JTS)
Specifies the implementation of a transaction manager
that supports JTA and implements the Java mapping of
the Object Management Group Object Transaction Service
1.1 specification at the level below the API.
139. What is JavaBeans component
A Java class that can be manipulated by tools and
composed into applications. A JavaBeans component must
adhere to certain property and event interface
conventions.
140. What is JavaMail
An API for sending and receiving email.
J2EE Interview questions and answers
121. What is J2EE product
An implementation that conforms to the J2EE platform
specification.
122. What is J2EE product provider
A vendor that supplies a J2EE product.
123. What is J2EE server
The runtime portion of a J2EE product. A J2EE server
provides EJB or Web containers or both.
124. What is J2ME
Abbreviate of Java 2 Platform, Micro Edition.
125. What is J2SE
Abbreviate of Java 2 Platform, Standard Edition.
126. What is JAR
Java archive. A platform-independent file format that
permits many files to be aggregated into one file.
127. What is Java 2 Platform, Enterprise Edition
(J2EE)
An environment for developing and deploying enterprise
applications. The J2EE platform consists of a set of
services, application programming interfaces (APIs),
and protocols that provide the functionality for
developing multitiered, Web-based applications.
128. What is Java 2 Platform, Micro Edition (J2ME)
A highly optimized Java runtime environment targeting
a wide range of consumer products, including pagers,
cellular phones, screen phones, digital set-top boxes,
and car navigation systems.
129. What is Java 2 Platform, Standard Edition (J2SE)
The core Java technology platform.
130. What is Java API for XML Processing (JAXP)
An API for processing XML documents. JAXP leverages
the parser standards SAX and DOM so that you can
choose to parse your data as a stream of events or to
build a tree-structured representation of it. JAXP
supports the XSLT standard, giving you control over
the presentation of the data and enabling you to
convert the data to other XML documents or to other
formats, such as HTML. JAXP provides namespace
support, allowing you to work with schema that might
otherwise have naming conflicts.
An implementation that conforms to the J2EE platform
specification.
122. What is J2EE product provider
A vendor that supplies a J2EE product.
123. What is J2EE server
The runtime portion of a J2EE product. A J2EE server
provides EJB or Web containers or both.
124. What is J2ME
Abbreviate of Java 2 Platform, Micro Edition.
125. What is J2SE
Abbreviate of Java 2 Platform, Standard Edition.
126. What is JAR
Java archive. A platform-independent file format that
permits many files to be aggregated into one file.
127. What is Java 2 Platform, Enterprise Edition
(J2EE)
An environment for developing and deploying enterprise
applications. The J2EE platform consists of a set of
services, application programming interfaces (APIs),
and protocols that provide the functionality for
developing multitiered, Web-based applications.
128. What is Java 2 Platform, Micro Edition (J2ME)
A highly optimized Java runtime environment targeting
a wide range of consumer products, including pagers,
cellular phones, screen phones, digital set-top boxes,
and car navigation systems.
129. What is Java 2 Platform, Standard Edition (J2SE)
The core Java technology platform.
130. What is Java API for XML Processing (JAXP)
An API for processing XML documents. JAXP leverages
the parser standards SAX and DOM so that you can
choose to parse your data as a stream of events or to
build a tree-structured representation of it. JAXP
supports the XSLT standard, giving you control over
the presentation of the data and enabling you to
convert the data to other XML documents or to other
formats, such as HTML. JAXP provides namespace
support, allowing you to work with schema that might
otherwise have naming conflicts.
J2EE Interview questions and answers
111. What is IDL
Interface Definition Language. A language used to
define interfaces to remote CORBA objects. The
interfaces are independent of operating systems and
programming languages.
112. What is IIOP
Internet Inter-ORB Protocol. A protocol used for
communication between CORBA object request brokers.
113. What is impersonation
An act whereby one entity assumes the identity and
privileges of another entity without restrictions and
without any indication visible to the recipients of
the impersonator's calls that delegation has taken
place. Impersonation is a case of simple delegation.
114. What is initialization parameter
A parameter that initializes the context associated
with a servlet
115. What is ISO 3166
The international standard for country codes
maintained by the International Organization for
Standardization (ISO).
116. What is ISV
Independent software vendor.
117. What is J2EE
Java 2 Platform, Enterprise Edition.
118. What is J2EE application
Any deployable unit of J2EE functionality. This can be
a single J2EE module or a group of modules packaged
into an EAR file along with a J2EE application
deployment descriptor. J2EE applications are typically
engineered to be distributed across multiple computing
tiers.
119. What is J2EE component
A self-contained functional software unit supported by
a container and configurable at deployment time. The
J2EE specification defines the following J2EE
components: Application clients and applets are
components that run on the client. Java servlet and
JavaServer Pages (JSP) technology components are Web
components that run on the server. Enterprise
JavaBeans (EJB) components (enterprise beans) are
business components that run on the server. J2EE
components are written in the Java programming
language and are compiled in the same way as any
program in the language. The difference between J2EE
components and "standard" Java classes is that J2EE
components are assembled into a J2EE application,
verified to be well formed and in compliance with the
J2EE specification, and deployed to production, where
they are run and managed by the J2EE server or client
container.
120. What is J2EE module
A software unit that consists of one or more J2EE
components of the same container type and one
deployment descriptor of that type. There are four
types of modules: EJB, Web, application client, and
resource adapter. Modules can be deployed as
stand-alone units or can be assembled into a J2EE
application.
Interface Definition Language. A language used to
define interfaces to remote CORBA objects. The
interfaces are independent of operating systems and
programming languages.
112. What is IIOP
Internet Inter-ORB Protocol. A protocol used for
communication between CORBA object request brokers.
113. What is impersonation
An act whereby one entity assumes the identity and
privileges of another entity without restrictions and
without any indication visible to the recipients of
the impersonator's calls that delegation has taken
place. Impersonation is a case of simple delegation.
114. What is initialization parameter
A parameter that initializes the context associated
with a servlet
115. What is ISO 3166
The international standard for country codes
maintained by the International Organization for
Standardization (ISO).
116. What is ISV
Independent software vendor.
117. What is J2EE
Java 2 Platform, Enterprise Edition.
118. What is J2EE application
Any deployable unit of J2EE functionality. This can be
a single J2EE module or a group of modules packaged
into an EAR file along with a J2EE application
deployment descriptor. J2EE applications are typically
engineered to be distributed across multiple computing
tiers.
119. What is J2EE component
A self-contained functional software unit supported by
a container and configurable at deployment time. The
J2EE specification defines the following J2EE
components: Application clients and applets are
components that run on the client. Java servlet and
JavaServer Pages (JSP) technology components are Web
components that run on the server. Enterprise
JavaBeans (EJB) components (enterprise beans) are
business components that run on the server. J2EE
components are written in the Java programming
language and are compiled in the same way as any
program in the language. The difference between J2EE
components and "standard" Java classes is that J2EE
components are assembled into a J2EE application,
verified to be well formed and in compliance with the
J2EE specification, and deployed to production, where
they are run and managed by the J2EE server or client
container.
120. What is J2EE module
A software unit that consists of one or more J2EE
components of the same container type and one
deployment descriptor of that type. There are four
types of modules: EJB, Web, application client, and
resource adapter. Modules can be deployed as
stand-alone units or can be assembled into a J2EE
application.
J2EE Interview questions and answers
101. What is form-based authentication
An authentication mechanism in which a Web container
provides an application-specific form for logging in.
This form of authentication uses Base64 encoding and
can expose user names and passwords unless all
connections are over SSL.
102. What is general entity
An entity that is referenced as part of an XML
document's content, as distinct from a parameter
entity, which is referenced in the DTD. A general
entity can be a parsed entity or an unparsed entity.
103. What is group
An authenticated set of users classified by common
traits such as job title or customer profile. Groups
are also associated with a set of roles, and every
user that is a member of a group inherits all the
roles assigned to that group.
104. What is handle
An object that identifies an enterprise bean. A client
can serialize the handle and then later deserialize it
to obtain a reference to the enterprise bean.
105. What is home handle
An object that can be used to obtain a reference to
the home interface. A home handle can be serialized
and written to stable storage and deserialized to
obtain the reference.
107. What is home interface
One of two interfaces for an enterprise bean. The home
interface defines zero or more methods for managing an
enterprise bean. The home interface of a session bean
defines create and remove methods, whereas the home
interface of an entity bean defines create, finder,
and remove methods.
108. What is HTML
Hypertext Markup Language. A markup language for
hypertext documents on the Internet. HTML enables the
embedding of images, sounds, video streams, form
fields, references to other objects with URLs, and
basic text formatting.
109. What is HTTP
Hypertext Transfer Protocol. The Internet protocol
used to retrieve hypertext objects from remote hosts.
HTTP messages consist of requests from client to
server and responses from server to client.
110. What is HTTPS
HTTP layered over the SSL protocol.
An authentication mechanism in which a Web container
provides an application-specific form for logging in.
This form of authentication uses Base64 encoding and
can expose user names and passwords unless all
connections are over SSL.
102. What is general entity
An entity that is referenced as part of an XML
document's content, as distinct from a parameter
entity, which is referenced in the DTD. A general
entity can be a parsed entity or an unparsed entity.
103. What is group
An authenticated set of users classified by common
traits such as job title or customer profile. Groups
are also associated with a set of roles, and every
user that is a member of a group inherits all the
roles assigned to that group.
104. What is handle
An object that identifies an enterprise bean. A client
can serialize the handle and then later deserialize it
to obtain a reference to the enterprise bean.
105. What is home handle
An object that can be used to obtain a reference to
the home interface. A home handle can be serialized
and written to stable storage and deserialized to
obtain the reference.
107. What is home interface
One of two interfaces for an enterprise bean. The home
interface defines zero or more methods for managing an
enterprise bean. The home interface of a session bean
defines create and remove methods, whereas the home
interface of an entity bean defines create, finder,
and remove methods.
108. What is HTML
Hypertext Markup Language. A markup language for
hypertext documents on the Internet. HTML enables the
embedding of images, sounds, video streams, form
fields, references to other objects with URLs, and
basic text formatting.
109. What is HTTP
Hypertext Transfer Protocol. The Internet protocol
used to retrieve hypertext objects from remote hosts.
HTTP messages consist of requests from client to
server and responses from server to client.
110. What is HTTPS
HTTP layered over the SSL protocol.
J2EE Interview questions and answers
91. What is an entity
A distinct, individual item that can be included in an
XML document by referencing it. Such an entity
reference can name an entity as small as a character
(for example, <, which references the less-than symbol
or left angle bracket, <). An entity reference can
also reference an entire document, an external entity,
or a collection of DTD definitions.
92. What is entity bean
An enterprise bean that represents persistent data
maintained in a database. An entity bean can manage
its own persistence or can delegate this function to
its container. An entity bean is identified by a
primary key. If the container in which an entity bean
is hosted crashes, the entity bean, its primary key,
and any remote references survive the crash.
93. What is entity reference
A reference to an entity that is substituted for the
reference when the XML document is parsed. It can
reference a predefined entity such as < or reference
one that is defined in the DTD. In the XML data, the
reference could be to an entity that is defined in the
local subset of the DTD or to an external XML file (an
external entity). The DTD can also carve out a segment
of DTD specifications and give it a name so that it
can be reused (included) at multiple points in the DTD
by defining a parameter entity.
94. What is error
A SAX parsing error is generally a validation error;
in other words, it occurs when an XML document is not
valid, although it can also occur if the declaration
specifies an XML version that the parser cannot
handle. See also fatal error, warning.
95. What is Extensible Markup Language
XML.
96. What is external entity
An entity that exists as an external XML file, which
is included in the XML document using an entity
reference.
96. What is external subset
That part of a DTD that is defined by references to
external DTD files.
97. What is fatal error
A fatal error occurs in the SAX parser when a document
is not well formed or otherwise cannot be processed.
See also error, warning.
98. What is filter
An object that can transform the header or content (or
both) of a request or response. Filters differ from
Web components in that they usually do not themselves
create responses but rather modify or adapt the
requests for a resource, and modify or adapt responses
from a resource. A filter should not have any
dependencies on a Web resource for which it is acting
as a filter so that it can be composable with more
than one type of Web resource.
99. What is filter chain
A concatenation of XSLT transformations in which the
output of one transformation becomes the input of the
next.
100. What is finder method
A method defined in the home interface and invoked by
a client to locate an entity bean.
A distinct, individual item that can be included in an
XML document by referencing it. Such an entity
reference can name an entity as small as a character
(for example, <, which references the less-than symbol
or left angle bracket, <). An entity reference can
also reference an entire document, an external entity,
or a collection of DTD definitions.
92. What is entity bean
An enterprise bean that represents persistent data
maintained in a database. An entity bean can manage
its own persistence or can delegate this function to
its container. An entity bean is identified by a
primary key. If the container in which an entity bean
is hosted crashes, the entity bean, its primary key,
and any remote references survive the crash.
93. What is entity reference
A reference to an entity that is substituted for the
reference when the XML document is parsed. It can
reference a predefined entity such as < or reference
one that is defined in the DTD. In the XML data, the
reference could be to an entity that is defined in the
local subset of the DTD or to an external XML file (an
external entity). The DTD can also carve out a segment
of DTD specifications and give it a name so that it
can be reused (included) at multiple points in the DTD
by defining a parameter entity.
94. What is error
A SAX parsing error is generally a validation error;
in other words, it occurs when an XML document is not
valid, although it can also occur if the declaration
specifies an XML version that the parser cannot
handle. See also fatal error, warning.
95. What is Extensible Markup Language
XML.
96. What is external entity
An entity that exists as an external XML file, which
is included in the XML document using an entity
reference.
96. What is external subset
That part of a DTD that is defined by references to
external DTD files.
97. What is fatal error
A fatal error occurs in the SAX parser when a document
is not well formed or otherwise cannot be processed.
See also error, warning.
98. What is filter
An object that can transform the header or content (or
both) of a request or response. Filters differ from
Web components in that they usually do not themselves
create responses but rather modify or adapt the
requests for a resource, and modify or adapt responses
from a resource. A filter should not have any
dependencies on a Web resource for which it is acting
as a filter so that it can be composable with more
than one type of Web resource.
99. What is filter chain
A concatenation of XSLT transformations in which the
output of one transformation becomes the input of the
next.
100. What is finder method
A method defined in the home interface and invoked by
a client to locate an entity bean.
J2EE Interview questions and answers
81. What is EJB object
An object whose class implements the enterprise bean's
remote interface. A client never references an
enterprise bean instance directly; a client always
references an EJB object. The class of an EJB object
is generated by a container's deployment tools.
82. What is EJB server
Software that provides services to an EJB container.
For example, an EJB container typically relies on a
transaction manager that is part of the EJB server to
perform the two-phase commit across all the
participating resource managers. The J2EE architecture
assumes that an EJB container is hosted by an EJB
server from the same vendor, so it does not specify
the contract between these two entities. An EJB server
can host one or more EJB containers.
83. What is EJB server provider
A vendor that supplies an EJB server.
83. What is EJB server provider
What is element
A unit of XML data, delimited by tags. An XML element
can enclose other elements.
84. What is empty tag
A tag that does not enclose any content
85. What is enterprise bean
A J2EE component that implements a business task or
business entity and is hosted by an EJB container;
either an entity bean, a session bean, or a
message-driven bean.
86. What is enterprise bean provider
An application developer who produces enterprise bean
classes, remote and home interfaces, and deployment
descriptor files, and packages them in an EJB JAR
file.
87. What is enterprise information system
The applications that constitute an enterprise's
existing system for handling companywide information.
These applications provide an information
infrastructure for an enterprise. An enterprise
information system offers a well-defined set of
services to its clients. These services are exposed to
clients as local or remote interfaces or both.
Examples of enterprise information systems include
enterprise resource planning systems, mainframe
transaction processing systems, and legacy database
systems.
88. What is enterprise information system resource
An entity that provides enterprise information
system-specific functionality to its clients. Examples
are a record or set of records in a database system, a
business object in an enterprise resource planning
system, and a transaction program in a transaction
processing system.
89. What is Enterprise JavaBeans (EJB)
A component architecture for the development and
deployment of object-oriented, distributed,
enterprise-level applications. Applications written
using the Enterprise JavaBeans architecture are
scalable, transactional, and secure.
90. What is Enterprise JavaBeans Query Language (EJB
QL)
Defines the queries for the finder and select methods
of an entity bean having container-managed
persistence. A subset of SQL92, EJB QL has extensions
that allow navigation over the relationships defined
in an entity bean's abstract schema.
An object whose class implements the enterprise bean's
remote interface. A client never references an
enterprise bean instance directly; a client always
references an EJB object. The class of an EJB object
is generated by a container's deployment tools.
82. What is EJB server
Software that provides services to an EJB container.
For example, an EJB container typically relies on a
transaction manager that is part of the EJB server to
perform the two-phase commit across all the
participating resource managers. The J2EE architecture
assumes that an EJB container is hosted by an EJB
server from the same vendor, so it does not specify
the contract between these two entities. An EJB server
can host one or more EJB containers.
83. What is EJB server provider
A vendor that supplies an EJB server.
83. What is EJB server provider
What is element
A unit of XML data, delimited by tags. An XML element
can enclose other elements.
84. What is empty tag
A tag that does not enclose any content
85. What is enterprise bean
A J2EE component that implements a business task or
business entity and is hosted by an EJB container;
either an entity bean, a session bean, or a
message-driven bean.
86. What is enterprise bean provider
An application developer who produces enterprise bean
classes, remote and home interfaces, and deployment
descriptor files, and packages them in an EJB JAR
file.
87. What is enterprise information system
The applications that constitute an enterprise's
existing system for handling companywide information.
These applications provide an information
infrastructure for an enterprise. An enterprise
information system offers a well-defined set of
services to its clients. These services are exposed to
clients as local or remote interfaces or both.
Examples of enterprise information systems include
enterprise resource planning systems, mainframe
transaction processing systems, and legacy database
systems.
88. What is enterprise information system resource
An entity that provides enterprise information
system-specific functionality to its clients. Examples
are a record or set of records in a database system, a
business object in an enterprise resource planning
system, and a transaction program in a transaction
processing system.
89. What is Enterprise JavaBeans (EJB)
A component architecture for the development and
deployment of object-oriented, distributed,
enterprise-level applications. Applications written
using the Enterprise JavaBeans architecture are
scalable, transactional, and secure.
90. What is Enterprise JavaBeans Query Language (EJB
QL)
Defines the queries for the finder and select methods
of an entity bean having container-managed
persistence. A subset of SQL92, EJB QL has extensions
that allow navigation over the relationships defined
in an entity bean's abstract schema.
J2EE Interview questions and answers
71. What is durable subscription
In a JMS publish/subscribe messaging system, a
subscription that continues to exist whether or not
there is a current active subscriber object. If there
is no active subscriber, the JMS provider retains the
subscription's messages until they are received by the
subscription or until they expire.
72. What is EAR file
Enterprise Archive file. A JAR archive that contains a
J2EE application.
73. What is ebXML
Electronic Business XML. A group of specifications
designed to enable enterprises to conduct business
through the exchange of XML-based messages. It is
sponsored by OASIS and the United Nations Centre for
the Facilitation of Procedures and Practices in
Administration, Commerce and Transport (U.N./CEFACT).
74. What is EJB
Enterprise JavaBeans.
75. What is EJB container
A container that implements the EJB component contract
of the J2EE architecture. This contract specifies a
runtime environment for enterprise beans that includes
security, concurrency, life-cycle management,
transactions, deployment, naming, and other services.
An EJB container is provided by an EJB or J2EE server.
76. What is EJB container provider
A vendor that supplies an EJB container.
77. What is EJB context
A vendor that supplies an EJB container. An object
that allows an enterprise bean to invoke services
provided by the container and to obtain the
information about the caller of a client-invoked
method.
78. What is EJB home object
An object that provides the life-cycle operations
(create, remove, find) for an enterprise bean. The
class for the EJB home object is generated by the
container's deployment tools. The EJB home object
implements the enterprise bean's home interface. The
client references an EJB home object to perform
life-cycle operations on an EJB object. The client
uses JNDI to locate an EJB home object
79. What is EJB JAR file
A JAR archive that contains an EJB module.
80. What is EJB module
A deployable unit that consists of one or more
enterprise beans and an EJB deployment descriptor.
In a JMS publish/subscribe messaging system, a
subscription that continues to exist whether or not
there is a current active subscriber object. If there
is no active subscriber, the JMS provider retains the
subscription's messages until they are received by the
subscription or until they expire.
72. What is EAR file
Enterprise Archive file. A JAR archive that contains a
J2EE application.
73. What is ebXML
Electronic Business XML. A group of specifications
designed to enable enterprises to conduct business
through the exchange of XML-based messages. It is
sponsored by OASIS and the United Nations Centre for
the Facilitation of Procedures and Practices in
Administration, Commerce and Transport (U.N./CEFACT).
74. What is EJB
Enterprise JavaBeans.
75. What is EJB container
A container that implements the EJB component contract
of the J2EE architecture. This contract specifies a
runtime environment for enterprise beans that includes
security, concurrency, life-cycle management,
transactions, deployment, naming, and other services.
An EJB container is provided by an EJB or J2EE server.
76. What is EJB container provider
A vendor that supplies an EJB container.
77. What is EJB context
A vendor that supplies an EJB container. An object
that allows an enterprise bean to invoke services
provided by the container and to obtain the
information about the caller of a client-invoked
method.
78. What is EJB home object
An object that provides the life-cycle operations
(create, remove, find) for an enterprise bean. The
class for the EJB home object is generated by the
container's deployment tools. The EJB home object
implements the enterprise bean's home interface. The
client references an EJB home object to perform
life-cycle operations on an EJB object. The client
uses JNDI to locate an EJB home object
79. What is EJB JAR file
A JAR archive that contains an EJB module.
80. What is EJB module
A deployable unit that consists of one or more
enterprise beans and an EJB deployment descriptor.
J2EE Interview questions and answers
61. What is declaration
The very first thing in an XML document, which
declares it as XML. The minimal declaration is . The
declaration is part of the document prolog.
62. What is declarative security
Mechanisms used in an application that are expressed
in a declarative syntax in a deployment descriptor.
63. What is delegation
An act whereby one principal authorizes another
principal to use its identity or privileges with some
restrictions.
64. What is deployer
A person who installs J2EE modules and applications
into an operational environment.
65. What is deployment
The process whereby software is installed into an
operational environment.
66. What is deployment descriptor
An XML file provided with each module and J2EE
application that describes how they should be
deployed. The deployment descriptor directs a
deployment tool to deploy a module or application with
specific container options and describes specific
configuration requirements that a deployer must
resolve.
67. What is destination
A JMS administered object that encapsulates the
identity of a JMS queue or topic. See point-to-point
messaging system, publish/subscribe messaging system.
68. What is digest authentication
An authentication mechanism in which a Web application
authenticates itself to a Web server by sending the
server a message digest along with its HTTP request
message. The digest is computed by employing a one-way
hash algorithm to a concatenation of the HTTP request
message and the client's password. The digest is
typically much smaller than the HTTP request and
doesn't contain the password.
69. What is distributed application
An application made up of distinct components running
in separate runtime environments, usually on different
platforms connected via a network. Typical distributed
applications are two-tier (client-server), three-tier
(client-middleware-server), and multitier
(client-multiple middleware-multiple servers).
67. What is document
In general, an XML structure in which one or more
elements contains text intermixed with subelements.
68. What is Document Object Model
An API for accessing and manipulating XML documents as
tree structures. DOM provides platform-neutral,
language-neutral interfaces that enables programs and
scripts to dynamically access and modify content and
structure in XML documents.
69. What is document root
The top-level directory of a WAR. The document root is
where JSP pages, client-side classes and archives, and
static Web resources are stored.
70. What is DTD
Document type definition. An optional part of the XML
document prolog, as specified by the XML standard. The
DTD specifies constraints on the valid tags and tag
sequences that can be in the document. The DTD has a
number of shortcomings, however, and this has led to
various schema proposals. For example, the DTD entry
says that the XML element called username contains
parsed character data-that is, text alone, with no
other structural elements under it. The DTD includes
both the local subset, defined in the current file,
and the external subset, which consists of the
definitions contained in external DTD files that are
referenced in the local subset using a parameter
entity.
The very first thing in an XML document, which
declares it as XML. The minimal declaration is . The
declaration is part of the document prolog.
62. What is declarative security
Mechanisms used in an application that are expressed
in a declarative syntax in a deployment descriptor.
63. What is delegation
An act whereby one principal authorizes another
principal to use its identity or privileges with some
restrictions.
64. What is deployer
A person who installs J2EE modules and applications
into an operational environment.
65. What is deployment
The process whereby software is installed into an
operational environment.
66. What is deployment descriptor
An XML file provided with each module and J2EE
application that describes how they should be
deployed. The deployment descriptor directs a
deployment tool to deploy a module or application with
specific container options and describes specific
configuration requirements that a deployer must
resolve.
67. What is destination
A JMS administered object that encapsulates the
identity of a JMS queue or topic. See point-to-point
messaging system, publish/subscribe messaging system.
68. What is digest authentication
An authentication mechanism in which a Web application
authenticates itself to a Web server by sending the
server a message digest along with its HTTP request
message. The digest is computed by employing a one-way
hash algorithm to a concatenation of the HTTP request
message and the client's password. The digest is
typically much smaller than the HTTP request and
doesn't contain the password.
69. What is distributed application
An application made up of distinct components running
in separate runtime environments, usually on different
platforms connected via a network. Typical distributed
applications are two-tier (client-server), three-tier
(client-middleware-server), and multitier
(client-multiple middleware-multiple servers).
67. What is document
In general, an XML structure in which one or more
elements contains text intermixed with subelements.
68. What is Document Object Model
An API for accessing and manipulating XML documents as
tree structures. DOM provides platform-neutral,
language-neutral interfaces that enables programs and
scripts to dynamically access and modify content and
structure in XML documents.
69. What is document root
The top-level directory of a WAR. The document root is
where JSP pages, client-side classes and archives, and
static Web resources are stored.
70. What is DTD
Document type definition. An optional part of the XML
document prolog, as specified by the XML standard. The
DTD specifies constraints on the valid tags and tag
sequences that can be in the document. The DTD has a
number of shortcomings, however, and this has led to
various schema proposals. For example, the DTD entry
says that the XML element called username contains
parsed character data-that is, text alone, with no
other structural elements under it. The DTD includes
both the local subset, defined in the current file,
and the external subset, which consists of the
definitions contained in external DTD files that are
referenced in the local subset using a parameter
entity.
J2EE Interview questions and answers
41. What is commit
The point in a transaction when all updates to any
resources involved in the transaction are made
permanent.
42. What is component contract
The contract between a J2EE component and its
container. The contract includes life-cycle management
of the component, a context interface that the
instance uses to obtain various information and
services from its container, and a list of services
that every container must provide for its components.
43. What is component-managed sign-on
A mechanism whereby security information needed for
signing on to a resource is provided by an application
component.
44. What is connector
A standard extension mechanism for containers that
provides connectivity to enterprise information
systems. A connector is specific to an enterprise
information system and consists of a resource adapter
and application development tools for enterprise
information system connectivity. The resource adapter
is plugged in to a container through its support for
system-level contracts defined in the Connector
architecture.
45. What is Connector architecture
An architecture for integration of J2EE products with
enterprise information systems. There are two parts to
this architecture: a resource adapter provided by an
enterprise information system vendor and the J2EE
product that allows this resource adapter to plug in.
This architecture defines a set of contracts that a
resource adapter must support to plug in to a J2EE
product-for example, transactions, security, and
resource management.
46. What is container
An entity that provides life-cycle management,
security, deployment, and runtime services to J2EE
components. Each type of container (EJB, Web, JSP,
servlet, applet, and application client) also provides
component-specific services.
47. What is container-managed persistence
The mechanism whereby data transfer between an entity
bean's variables and a resource manager is managed by
the entity bean's container.
48. What is container-managed sign-on
The mechanism whereby security information needed for
signing on to a resource is supplied by the container.
49. What is container-managed transaction
A transaction whose boundaries are defined by an EJB
container. An entity bean must use container-managed
transactions.
50. What is content
In an XML document, the part that occurs after the
prolog, including the root element and everything it
contains.
The point in a transaction when all updates to any
resources involved in the transaction are made
permanent.
42. What is component contract
The contract between a J2EE component and its
container. The contract includes life-cycle management
of the component, a context interface that the
instance uses to obtain various information and
services from its container, and a list of services
that every container must provide for its components.
43. What is component-managed sign-on
A mechanism whereby security information needed for
signing on to a resource is provided by an application
component.
44. What is connector
A standard extension mechanism for containers that
provides connectivity to enterprise information
systems. A connector is specific to an enterprise
information system and consists of a resource adapter
and application development tools for enterprise
information system connectivity. The resource adapter
is plugged in to a container through its support for
system-level contracts defined in the Connector
architecture.
45. What is Connector architecture
An architecture for integration of J2EE products with
enterprise information systems. There are two parts to
this architecture: a resource adapter provided by an
enterprise information system vendor and the J2EE
product that allows this resource adapter to plug in.
This architecture defines a set of contracts that a
resource adapter must support to plug in to a J2EE
product-for example, transactions, security, and
resource management.
46. What is container
An entity that provides life-cycle management,
security, deployment, and runtime services to J2EE
components. Each type of container (EJB, Web, JSP,
servlet, applet, and application client) also provides
component-specific services.
47. What is container-managed persistence
The mechanism whereby data transfer between an entity
bean's variables and a resource manager is managed by
the entity bean's container.
48. What is container-managed sign-on
The mechanism whereby security information needed for
signing on to a resource is supplied by the container.
49. What is container-managed transaction
A transaction whose boundaries are defined by an EJB
container. An entity bean must use container-managed
transactions.
50. What is content
In an XML document, the part that occurs after the
prolog, including the root element and everything it
contains.
J2EE Interview questions and answers
21. What is business logic
The code that implements the functionality of an
application. In the Enterprise JavaBeans architecture,
this logic is implemented by the methods of an
enterprise bean.
22.What is business method
A method of an enterprise bean that implements the
business logic or rules of an application.
23. What is callback methods
Component methods called by the container to notify
the component of important events in its life cycle.
24. What is caller
Same as caller principal.
25. What is caller principal
The principal that identifies the invoker of the
enterprise bean method.
26. What is cascade delete
A deletion that triggers another deletion. A cascade
delete can be specified for an entity bean that has
container-managed persistence.
27. What is CDATA
A predefined XML tag for character data that means
"don't interpret these characters," as opposed to
parsed character data (PCDATA), in which the normal
rules of XML syntax apply. CDATA sections are
typically used to show examples of XML syntax.
28. What is certificate authority
A trusted organization that issues public key
certificates and provides identification to the
bearer.
29. What is client-certificate authentication
An authentication mechanism that uses HTTP over SSL,
in which the server and, optionally, the client
authenticate each other with a public key certificate
that conforms to a standard that is defined by X.509
Public Key Infrastructure.
30. What is comment
In an XML document, text that is ignored unless the
parser is specifically told to recognize it.
The code that implements the functionality of an
application. In the Enterprise JavaBeans architecture,
this logic is implemented by the methods of an
enterprise bean.
22.What is business method
A method of an enterprise bean that implements the
business logic or rules of an application.
23. What is callback methods
Component methods called by the container to notify
the component of important events in its life cycle.
24. What is caller
Same as caller principal.
25. What is caller principal
The principal that identifies the invoker of the
enterprise bean method.
26. What is cascade delete
A deletion that triggers another deletion. A cascade
delete can be specified for an entity bean that has
container-managed persistence.
27. What is CDATA
A predefined XML tag for character data that means
"don't interpret these characters," as opposed to
parsed character data (PCDATA), in which the normal
rules of XML syntax apply. CDATA sections are
typically used to show examples of XML syntax.
28. What is certificate authority
A trusted organization that issues public key
certificates and provides identification to the
bearer.
29. What is client-certificate authentication
An authentication mechanism that uses HTTP over SSL,
in which the server and, optionally, the client
authenticate each other with a public key certificate
that conforms to a standard that is defined by X.509
Public Key Infrastructure.
30. What is comment
In an XML document, text that is ignored unless the
parser is specifically told to recognize it.
J2EE Interview questions and answers
14. What is backing bean
A JavaBeans component that corresponds to a JSP page
that includes JavaServer Faces components. The backing
bean defines properties for the components on the page
and methods that perform processing for the component.
This processing includes event handling, validation,
and processing associated with navigation.
15. What is basic authentication
An authentication mechanism in which a Web server
authenticates an entity via a user name and password
obtained using the Web application's built-in
authentication mechanism.
16. What is bean-managed persistence
The mechanism whereby data transfer between an entity
bean's variables and a resource manager is managed by
the entity bean.
17. What is bean-managed transaction
A transaction whose boundaries are defined by an
enterprise bean.
18. What is binding (XML)
Generating the code needed to process a well-defined
portion of XML data.
19. What is binding (JavaServer Faces technology)
Wiring UI components to back-end data sources such as
backing bean properties.
20. What is build file
The XML file that contains one or more asant targets.
A target is a set of tasks you want to be executed.
When starting asant, you can select which targets you
want to have executed. When no target is given, the
project's default target is executed.
A JavaBeans component that corresponds to a JSP page
that includes JavaServer Faces components. The backing
bean defines properties for the components on the page
and methods that perform processing for the component.
This processing includes event handling, validation,
and processing associated with navigation.
15. What is basic authentication
An authentication mechanism in which a Web server
authenticates an entity via a user name and password
obtained using the Web application's built-in
authentication mechanism.
16. What is bean-managed persistence
The mechanism whereby data transfer between an entity
bean's variables and a resource manager is managed by
the entity bean.
17. What is bean-managed transaction
A transaction whose boundaries are defined by an
enterprise bean.
18. What is binding (XML)
Generating the code needed to process a well-defined
portion of XML data.
19. What is binding (JavaServer Faces technology)
Wiring UI components to back-end data sources such as
backing bean properties.
20. What is build file
The XML file that contains one or more asant targets.
A target is a set of tasks you want to be executed.
When starting asant, you can select which targets you
want to have executed. When no target is given, the
project's default target is executed.
J2EE Interview questions and answers
10. What is "applet container"
A container that includes support for the applet
programming model.
11. What is authorization?
The process by which access to a method or resource is
determined. Authorization depends on the determination
of whether the principal associated with a request
through authentication is in a given security role. A
security role is a logical grouping of users defined
by the person who assembles the application. A
deployer maps security roles to security identities.
Security identities may be principals or groups in the
operational environment.
12. What is authorization constraint
An authorization rule that determines who is permitted
to access a Web resource collection.
13. What is B2B
B2B stands for Business-to-business.
A container that includes support for the applet
programming model.
11. What is authorization?
The process by which access to a method or resource is
determined. Authorization depends on the determination
of whether the principal associated with a request
through authentication is in a given security role. A
security role is a logical grouping of users defined
by the person who assembles the application. A
deployer maps security roles to security identities.
Security identities may be principals or groups in the
operational environment.
12. What is authorization constraint
An authorization rule that determines who is permitted
to access a Web resource collection.
13. What is B2B
B2B stands for Business-to-business.
J2EE Interview questions and answers
8. What is the difference between Session bean and
Entity bean?one?
The Session bean and Entity bean are two main parts of
EJB container.
Session Bean
--represents a workflow on behalf of a cliennt
--one-to-one logical mapping to a client. --created
and destroyed by a client
--not permanent objects
--lives its EJB container(generally) does noot survive
system shut down
--two types: stateless and stateful beans Entity Bean
--represents persistent data and behavior off this
data
--can be shared among multiple clients
--persists across multiple invocations
--findable permanent objects
--outlives its EJB container, survives systeem
shutdown
--two types: container managed persistence(CCMP) and
bean managed persistence(BMP)
9. What is "applet"
A J2EE component that typically executes in a Web
browser but can execute in a variety of other
applications or devices that support the applet
programming model.
Entity bean?one?
The Session bean and Entity bean are two main parts of
EJB container.
Session Bean
--represents a workflow on behalf of a cliennt
--one-to-one logical mapping to a client. --created
and destroyed by a client
--not permanent objects
--lives its EJB container(generally) does noot survive
system shut down
--two types: stateless and stateful beans Entity Bean
--represents persistent data and behavior off this
data
--can be shared among multiple clients
--persists across multiple invocations
--findable permanent objects
--outlives its EJB container, survives systeem
shutdown
--two types: container managed persistence(CCMP) and
bean managed persistence(BMP)
9. What is "applet"
A J2EE component that typically executes in a Web
browser but can execute in a variety of other
applications or devices that support the applet
programming model.
J2EE Interview questions and answers
7. What are the differences between Ear, Jar and War
files? Under what circumstances should we use each
one?
There are no structural differences between the files;
they are all archived using zip-jar compression.
However, they are intended for different purposes.
--Jar files (files with a .jar extension) arre
intended to hold generic libraries of Java classes,
resources, auxiliary files, etc.
--War files (files with a .war extension) arre
intended to contain complete Web applications. In this
context, a Web application is defined as a single
group of files, classes, resources, .jar files that
can be packaged and accessed as one servlet context.
--Ear files (files with a .ear extension) arre
intended to contain complete enterprise applications.
In this context, an enterprise application is defined
as a collection of .jar files, resources, classes, and
multiple Web applications.
Each type of file (.jar, .war, .ear) is processed
uniquely by application servers, servlet containers,
EJB containers, etc.
files? Under what circumstances should we use each
one?
There are no structural differences between the files;
they are all archived using zip-jar compression.
However, they are intended for different purposes.
--Jar files (files with a .jar extension) arre
intended to hold generic libraries of Java classes,
resources, auxiliary files, etc.
--War files (files with a .war extension) arre
intended to contain complete Web applications. In this
context, a Web application is defined as a single
group of files, classes, resources, .jar files that
can be packaged and accessed as one servlet context.
--Ear files (files with a .ear extension) arre
intended to contain complete enterprise applications.
In this context, an enterprise application is defined
as a collection of .jar files, resources, classes, and
multiple Web applications.
Each type of file (.jar, .war, .ear) is processed
uniquely by application servers, servlet containers,
EJB containers, etc.
J2EE Interview questions and answers
3. What are the components of J2EE application?
A J2EE component is a self-contained functional
software unit that is assembled into a J2EE
application with its related classes and files and
communicates with other components. The J2EE
specification defines the following J2EE components:
Application clients and applets are client components.
Java Servlet and JavaServer PagesTM (JSPTM) technology
components are web components.
Enterprise JavaBeansTM (EJBTM) components (enterprise
beans) are business components.
Resource adapter components provided by EIS and tool
vendors.
4. What are the four types of J2EE modules?
1. Application client module
2. Web module
3. Enterprise JavaBeans module
4. Resource adapter module
5. What does application client module contain?
The application client module contains:
--class files,
--an application client deployment descriptoor.
Application client modules are packaged as JAR files
with a .jar extension.
6. What does web module contain?
The web module contains:
--JSP files,
--class files for servlets,
--GIF and HTML files, and
--a Web deployment descriptor.
Web modules are packaged as JAR files with a .war (Web
ARchive) extension.
A J2EE component is a self-contained functional
software unit that is assembled into a J2EE
application with its related classes and files and
communicates with other components. The J2EE
specification defines the following J2EE components:
Application clients and applets are client components.
Java Servlet and JavaServer PagesTM (JSPTM) technology
components are web components.
Enterprise JavaBeansTM (EJBTM) components (enterprise
beans) are business components.
Resource adapter components provided by EIS and tool
vendors.
4. What are the four types of J2EE modules?
1. Application client module
2. Web module
3. Enterprise JavaBeans module
4. Resource adapter module
5. What does application client module contain?
The application client module contains:
--class files,
--an application client deployment descriptoor.
Application client modules are packaged as JAR files
with a .jar extension.
6. What does web module contain?
The web module contains:
--JSP files,
--class files for servlets,
--GIF and HTML files, and
--a Web deployment descriptor.
Web modules are packaged as JAR files with a .war (Web
ARchive) extension.
J2EE Interview questions and answers
J2EE Interview questions and answers
1. What is J2EE?
J2EE is an environment for developing and deploying
enterprise applications. The J2EE platform consists of
a set of services, application programming interfaces
(APIs), and protocols that provide the functionality
for developing multitiered, web-based applications.
2. What is the J2EE module?
A J2EE module consists of one or more J2EE components
for the same container type and one component
deployment descriptor of that type.
1. What is J2EE?
J2EE is an environment for developing and deploying
enterprise applications. The J2EE platform consists of
a set of services, application programming interfaces
(APIs), and protocols that provide the functionality
for developing multitiered, web-based applications.
2. What is the J2EE module?
A J2EE module consists of one or more J2EE components
for the same container type and one component
deployment descriptor of that type.
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