Read the most frequently asked 100 top J2EE interview questions and answers for freshers and experienced.....
J2EE Interview Questions and Answers PDF Experienced Freshers
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.
3. What are the four types of J2EE modules?
1. Application client module
2. Web module
3. Enterprise JavaBeans module
4. Resource adapter module
4. 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.
5. 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 client
--one-to-one logical mapping to a client.
--created and destroyed by a client
--not permanent objects
--lives its EJB container(generally) does not survive system shut down
--two types: stateless and stateful beans
Entity Bean
--represents persistent data and behavior of this data
--can be shared among multiple clients
--persists across multiple invocations
--findable permanent objects
--outlives its EJB container, survives system shutdown
--two types: container managed persistence(CMP) and bean managed persistence(BMP)
6. What is applet container?
A container that includes support for the applet programming model.
7. What is application client?
A first-tier J2EE client component that executes in its own Java virtual machine. Application clients have access to some J2EE platform APIs.
8. What is application client module?
A software unit that consists of one or more classes and an application client deployment descriptor.
9. What is application configuration resource file?
An XML file used to configure resources for a JavaServer Faces application, to define navigation rules for the application, and to register converters, validators, listeners, renderers, and components with the application.
10. What is asant?
A Java-based build tool that can be extended using Java classes. The configuration files are XML-based, calling out a target tree where various tasks get executed.
11. What is authorization constraint?
An authorization rule that determines who is permitted to access a Web resource collection.
12. 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.
13. 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.
14. What is binding (XML)?
Generating the code needed to process a well-defined portion of XML data.
15. 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.
16. What is business method?
A method of an enterprise bean that implements the business logic or rules of an application.
17. What is caller?
Same as caller principal.
18. 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.
19. 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.
20. 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.
21. What is certificate authority?
A trusted organization that issues public key certificates and provides identification to the bearer.
22. What is caller principal?
The principal that identifies the invoker of the enterprise bean method.
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 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.
25. What is binding (JavaServer Faces technology)?
Wiring UI components to back-end data sources such as backing bean properties.
26. What is bean-managed transaction?
A transaction whose boundaries are defined by an enterprise bean.
27. 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.
28. What is B2B?
B2B stands for Business-to-business.
29. 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.
30. What is attribute What is asant?
A qualifier on an XML tag that provides additional information.
31. What is archiving?
The process of saving the state of an object and restoring it.
32. What is application component provider?
A vendor that provides the Java classes that implement components' methods, JSP page definitions, and any required deployment descriptors.
33. What is application client container?
A container that supports application client components.
34. What is application assembler?
A person who combines J2EE components and modules into deployable application units.
35. 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) are intended to hold generic libraries of Java classes, resources, auxiliary files, etc.
--War files (files with a .war extension) are 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) are 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.
36. What does application client module contain?
The application client module contains:
--class files,
--an application client deployment descriptor.
Application client modules are packaged as JAR files with a .jar extension.
37. 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.
38. 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.
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 component-managed sign-on?
A mechanism whereby security information needed for signing on to a resource is provided by an application component.
41. 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.
42. 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.
43. What is container-managed transaction?
A transaction whose boundaries are defined by an EJB container. An entity bean must use container-managed transactions.
44. What is context attribute?
An object bound into the context associated with a servlet.
45. What is create method?
A method defined in the home interface and invoked by a client to create an enterprise bean.
46. 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.
47. 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.
48. 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.
49. 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.
50. What is document?
In general, an XML structure in which one or more elements contains text intermixed with subelements.
51. 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.
52. 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.
53. 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).
54. What is EJB JAR file?
A JAR archive that contains an EJB module.
55. What is EJB server provider?
A vendor that supplies an EJB server.
56. What is empty tag?
A tag that does not enclose any content.
57. 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.
58. 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.
59. 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.
60. What is external entity?
An entity that exists as an external XML file, which is included in the XML document using an entity reference.
61. 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.
62. What is filter chain?
A concatenation of XSLT transformations in which the output of one transformation becomes the input of the next.
63. 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.
64. 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.
65. What is ISO 3166?
The international standard for country codes maintained by the International Organization for Standardization (ISO).
66. 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.
67. 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.
68. What is finder method?
A method defined in the home interface and invoked by a client to locate an entity bean.
69. What is external subset?
That part of a DTD that is defined by references to external DTD files.
70. What is Extensible Markup Language?
XML.
71. 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.
72. 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.
73. What is EJB module?
A deployable unit that consists of one or more enterprise beans and an EJB deployment descriptor.
74. What is EJB container provider?
A vendor that supplies an EJB container.
75. What is EAR file?
Enterprise Archive file. A JAR archive that contains a J2EE application.
76. 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.
77. 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.
78. What is deployer?
A person who installs J2EE modules and applications into an operational environment.
79. What is deployment?
The process whereby software is installed into an operational environment.
80. What is declarative security?
Mechanisms used in an application that are expressed in a declarative syntax in a deployment descriptor.
81. What is DDP?
Document-driven programming. The use of XML to define applications.
82. What is CTS?
Compatibility test suite. A suite of compatibility tests for verifying that a J2EE product complies with the J2EE platform specification.
83. What is context root?
A name that gets mapped to the document root of a Web application.
84. What is content?
In an XML document, the part that occurs after the prolog, including the root element and everything it contains.
85. What is container-managed sign-on?
The mechanism whereby security information needed for signing on to a resource is supplied by the container.
86. 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.
87. What is initialization parameter?
A parameter that initializes the context associated with a servlet.
88. What is ISV?
Independent software vendor.
89. 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.
90. What is J2EE product?
An implementation that conforms to the J2EE platform specification.
91. What is J2EE server?
The runtime portion of a J2EE product. A J2EE server provides EJB or Web containers or both.
92. What is J2SE?
Abbreviate of Java 2 Platform, Standard Edition.
93. 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.
94. What is Java 2 Platform, Standard Edition (J2SE)?
The core Java technology platform.
95. What is Java API for XML Registries (JAXR)?
An API for accessing various kinds of XML registries.
96. What is Java Transaction API (JTA)?
An API that allows applications and J2EE servers to access transactions.
97. 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.
98. 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.
99. What is JAXR client?
A client program that uses the JAXR API to access a business registry via a JAXR provider.
100. What is JMS client?
A Java language program that sends or receives messages.
J2EE Interview Questions and Answers PDF Experienced Freshers
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.
3. What are the four types of J2EE modules?
1. Application client module
2. Web module
3. Enterprise JavaBeans module
4. Resource adapter module
4. 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.
5. 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 client
--one-to-one logical mapping to a client.
--created and destroyed by a client
--not permanent objects
--lives its EJB container(generally) does not survive system shut down
--two types: stateless and stateful beans
Entity Bean
--represents persistent data and behavior of this data
--can be shared among multiple clients
--persists across multiple invocations
--findable permanent objects
--outlives its EJB container, survives system shutdown
--two types: container managed persistence(CMP) and bean managed persistence(BMP)
6. What is applet container?
A container that includes support for the applet programming model.
7. What is application client?
A first-tier J2EE client component that executes in its own Java virtual machine. Application clients have access to some J2EE platform APIs.
8. What is application client module?
A software unit that consists of one or more classes and an application client deployment descriptor.
9. What is application configuration resource file?
An XML file used to configure resources for a JavaServer Faces application, to define navigation rules for the application, and to register converters, validators, listeners, renderers, and components with the application.
10. What is asant?
A Java-based build tool that can be extended using Java classes. The configuration files are XML-based, calling out a target tree where various tasks get executed.
11. What is authorization constraint?
An authorization rule that determines who is permitted to access a Web resource collection.
12. 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.
13. 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.
14. What is binding (XML)?
Generating the code needed to process a well-defined portion of XML data.
15. 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.
16. What is business method?
A method of an enterprise bean that implements the business logic or rules of an application.
17. What is caller?
Same as caller principal.
18. 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.
19. 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.
20. 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.
21. What is certificate authority?
A trusted organization that issues public key certificates and provides identification to the bearer.
22. What is caller principal?
The principal that identifies the invoker of the enterprise bean method.
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 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.
25. What is binding (JavaServer Faces technology)?
Wiring UI components to back-end data sources such as backing bean properties.
26. What is bean-managed transaction?
A transaction whose boundaries are defined by an enterprise bean.
27. 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.
28. What is B2B?
B2B stands for Business-to-business.
29. 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.
30. What is attribute What is asant?
A qualifier on an XML tag that provides additional information.
31. What is archiving?
The process of saving the state of an object and restoring it.
32. What is application component provider?
A vendor that provides the Java classes that implement components' methods, JSP page definitions, and any required deployment descriptors.
33. What is application client container?
A container that supports application client components.
34. What is application assembler?
A person who combines J2EE components and modules into deployable application units.
35. 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) are intended to hold generic libraries of Java classes, resources, auxiliary files, etc.
--War files (files with a .war extension) are 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) are 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.
36. What does application client module contain?
The application client module contains:
--class files,
--an application client deployment descriptor.
Application client modules are packaged as JAR files with a .jar extension.
37. 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.
38. 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.
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 component-managed sign-on?
A mechanism whereby security information needed for signing on to a resource is provided by an application component.
41. 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.
42. 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.
43. What is container-managed transaction?
A transaction whose boundaries are defined by an EJB container. An entity bean must use container-managed transactions.
44. What is context attribute?
An object bound into the context associated with a servlet.
45. What is create method?
A method defined in the home interface and invoked by a client to create an enterprise bean.
46. 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.
47. 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.
48. 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.
49. 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.
50. What is document?
In general, an XML structure in which one or more elements contains text intermixed with subelements.
51. 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.
52. 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.
53. 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).
54. What is EJB JAR file?
A JAR archive that contains an EJB module.
55. What is EJB server provider?
A vendor that supplies an EJB server.
56. What is empty tag?
A tag that does not enclose any content.
57. 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.
58. 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.
59. 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.
60. What is external entity?
An entity that exists as an external XML file, which is included in the XML document using an entity reference.
61. 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.
62. What is filter chain?
A concatenation of XSLT transformations in which the output of one transformation becomes the input of the next.
63. 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.
64. 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.
65. What is ISO 3166?
The international standard for country codes maintained by the International Organization for Standardization (ISO).
66. 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.
67. 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.
68. What is finder method?
A method defined in the home interface and invoked by a client to locate an entity bean.
69. What is external subset?
That part of a DTD that is defined by references to external DTD files.
70. What is Extensible Markup Language?
XML.
71. 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.
72. 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.
73. What is EJB module?
A deployable unit that consists of one or more enterprise beans and an EJB deployment descriptor.
74. What is EJB container provider?
A vendor that supplies an EJB container.
75. What is EAR file?
Enterprise Archive file. A JAR archive that contains a J2EE application.
76. 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.
77. 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.
78. What is deployer?
A person who installs J2EE modules and applications into an operational environment.
79. What is deployment?
The process whereby software is installed into an operational environment.
80. What is declarative security?
Mechanisms used in an application that are expressed in a declarative syntax in a deployment descriptor.
81. What is DDP?
Document-driven programming. The use of XML to define applications.
82. What is CTS?
Compatibility test suite. A suite of compatibility tests for verifying that a J2EE product complies with the J2EE platform specification.
83. What is context root?
A name that gets mapped to the document root of a Web application.
84. What is content?
In an XML document, the part that occurs after the prolog, including the root element and everything it contains.
85. What is container-managed sign-on?
The mechanism whereby security information needed for signing on to a resource is supplied by the container.
86. 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.
87. What is initialization parameter?
A parameter that initializes the context associated with a servlet.
88. What is ISV?
Independent software vendor.
89. 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.
90. What is J2EE product?
An implementation that conforms to the J2EE platform specification.
91. What is J2EE server?
The runtime portion of a J2EE product. A J2EE server provides EJB or Web containers or both.
92. What is J2SE?
Abbreviate of Java 2 Platform, Standard Edition.
93. 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.
94. What is Java 2 Platform, Standard Edition (J2SE)?
The core Java technology platform.
95. What is Java API for XML Registries (JAXR)?
An API for accessing various kinds of XML registries.
96. What is Java Transaction API (JTA)?
An API that allows applications and J2EE servers to access transactions.
97. 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.
98. 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.
99. What is JAXR client?
A client program that uses the JAXR API to access a business registry via a JAXR provider.
100. What is JMS client?
A Java language program that sends or receives messages.
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