J2EE Interview questions and answers

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.

A J2EE module consists of one or more J2EE components for the same container type and one component deployment descriptor of that type.

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.

The application client module contains:
--class files,
--an application client deployment descriptoor.
Application client modules are packaged as JAR files with a .jar extension.

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.

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.

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)

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.

A container that includes support for the applet programming model.

21. 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. 


22. What is authorization constraint 

An authorization rule that determines who is permitted
to access a Web resource collection. 

23. What is B2B 

B2B stands for Business-to-business. 

24. 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. 

25. 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. 

26. 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. 

27. What is bean-managed transaction 

A transaction whose boundaries are defined by an
enterprise bean. 

28. What is binding (XML) 

Generating the code needed to process a well-defined
portion of XML data. 

29. What is binding (JavaServer Faces technology) 

Wiring UI components to back-end data sources such as
backing bean properties. 

30. 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. 



31. 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. 

32.What is business method 

A method of an enterprise bean that implements the
business logic or rules of an application. 

33. What is callback methods 

Component methods called by the container to notify
the component of important events in its life cycle. 

34. What is caller 

Same as caller principal. 

35. What is caller principal 

The principal that identifies the invoker of the
enterprise bean method. 

36. 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. 

37. 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. 

38. What is certificate authority 

A trusted organization that issues public key
certificates and provides identification to the
bearer. 

39. 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. 

40. What is comment 

In an XML document, text that is ignored unless the
parser is specifically told to recognize it. 


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. 

51. What is context attribute 

An object bound into the context associated with a
servlet. 

52. What is context root 

A name that gets mapped to the document root of a Web
application. 

53. What is conversational state 

The field values of a session bean plus the transitive
closure of the objects reachable from the bean's
fields. The transitive closure of a bean is defined in
terms of the serialization protocol for the Java
programming language, that is, the fields that would
be stored by serializing the bean instance. 

54. What is CORBA 

Common Object Request Broker Architecture. A
language-independent distributed object model
specified by the OMG. 

55. What is create method 

A method defined in the home interface and invoked by
a client to create an enterprise bean. 

56. What is credentials 

The information describing the security attributes of
a principal. 

57. What is CSS 

Cascading style sheet. A stylesheet used with HTML and
XML documents to add a style to all elements marked
with a particular tag, for the direction of browsers
or other presentation mechanisms. 

58. What is CTS 

Compatibility test suite. A suite of compatibility
tests for verifying that a J2EE product complies with
the J2EE platform specification. 

59. What is data 

The contents of an element in an XML stream, generally
used when the element does not contain any
subelements. When it does, the term content is
generally used. When the only text in an XML structure
is contained in simple elements and when elements that
have subelements have little or no data mixed in, then
that structure is often thought of as XML data, as
opposed to an XML document. 

60. What is DDP 

Document-driven programming. The use of XML to define
applications. 

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. 

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. 

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.


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. 

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. 

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. 


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. 


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. 


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. 


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. 

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. 

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. 


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. 

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.