J2EE Interview Tips Part 4
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.
(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.
