Java Enterprise and Web Technologies

In EJB Container-Managed Persistence (CMP), the ejbCreate() method must return null (or the primary key type, but per the EJB specification, the container manages primary key generation/mapping and CMP bean's ejbCreate() returns null so the container can initialize the primary key). The Home Object and Remote Object are client-side references, not returned by bean lifecycle methods.

When a new window is opened via JavaScript from a JSP page, session cookies are passed to the new window if it's within the same domain. This means the existing HTTP session remains valid and accessible in the new window. Option A is incorrect because sessions do persist across window opens. Option C is incorrect because a new session is not automatically created.

The servlet lifecycle follows init() for initialization, service() for processing requests, and destroy() for cleanup. The service() method is called repeatedly for each request until the servlet is destroyed.

A web module comprises JSP pages for presentation, Java classes for business logic (servlets, utilities), HTML for static content, and deployment descriptors (web.xml) for configuration. All four are essential components.

Session tracking is the mechanism servlets use to maintain state information about a series of requests from the same user across multiple HTTP connections, which are otherwise stateless.

In J2EE MVC architecture, the Model represents business logic and data, typically implemented as Java classes (EJBs or POJOs). The Model handles data access, business rules, and application state, independent of the View or Controller.

In J2EE MVC architecture, the View handles presentation and user interface, typically implemented as JSP (JavaServer Pages). JSPs combine HTML with Java code to dynamically generate web pages for display.

JSP provides several implicit objects (predefined variables) including request (HttpServletRequest), response (HttpServletResponse), session (HttpSession), out, application, config, page, and pageContext - all automatically available without declaration.

Apache Struts is an MVC framework that combines Java Servlets, JSP, custom tags, and message resources into a unified architecture for building web applications, providing structure and reusable components.

A Java EE/Jakarta EE web module contains web components such as JSP files, static resources (HTML, GIF), Java classes (servlets/beans), and deployment descriptors (web.xml). Therefore, all the listed components are correct.

Servlets are Java programs that extend server capabilities, handling client requests and generating dynamic responses. They run within a web container and provide request/response processing functionality for Java-enabled web servers, making them ideal modular extensions.

The servlet container (such as Tomcat or Jetty) is responsible for managing the servlet lifecycle, which includes instantiating the servlet class and invoking its init() method.

Java Web Server, JRun, and Apache Server (configured with a servlet container like Tomcat) are all historically valid servers capable of developing and deploying Java Servlets. Thus, 'All the above' is correct.

In MVC architecture implemented with servlets, the Servlet acts as the Controller, receiving requests and routing them to appropriate Model components and View pages. The Controller handles request processing flow, not direct database connections, page display, or frontend validations which are handled by other components.

Stateful session beans in EJB (Enterprise JavaBeans) architecture consist of three components: the Home Interface for lifecycle management, the Remote Interface for client access, and the Bean Class containing business logic.