J2EE Interviews Question page13

1. What is keystore ?
   A file containing the keys and certificates used for authentication
     
2. 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.
     
3. 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.
     
4. What is local subset ?
   That part of the DTD that is defined within the current XML file.
     
5. What is managed bean creation facility ?
   A mechanism for defining the characteristics of JavaBeans components used in a JavaServer Faces application.
     
6. 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.
    
7. What is message consumer ?
   An object created by a JMS session that is used for receiving messages sent to a destination.
     
8. 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.
      
9. What is message producer ?
   An object created by a JMS session that is used for sending messages to a destination.
   
10. 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 (*).
      
11. What is method-binding expression ?
    A Java Server 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.
     
12. What is method permission ?
    An authorization rule that determines who is permitted to execute one or more enterprise bean methods.
      
13. What is mutual authentication ?
    An authentication mechanism employed by two parties for the purpose of proving each other's identity to one another.
        
14. 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.
      
15. What is naming context ?
    A set of associations between unique, atomic, people-friendly identifiers and objects.
     
16. 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.
       
17. What is normalization ?
    The process of removing redundancy by modularizing, as with subroutines, and of removing superfluous differences by reducing them to a common denominator. For example, line endings from different systems are normalized by reducing them to a single new line, and multiple whitespace characters are normalized to one space.