Java Web Development - Servlets and JSP

The key advantage of JSP over Servlet is that it allows embedding Java code directly in HTML, making it easier to maintain the presentation layer. Options B, C, and D are capabilities shared by both JSP and Servlets - they're platform-independent, can create database-driven apps, and both are server-side technologies.

JSP lifecycle methods are jspInit() (called once when JSP is initialized), _jspService() (called for each request, equivalent to service() in servlets), and jspDestroy() (called when JSP is destroyed). Option B lists servlet lifecycle methods. Option C is only one method (doPost is HTTP method handler, not lifecycle).

In the MVC (Model-View-Controller) architecture, JSP serves as the View component - it handles presentation and display. The Model represents data and business logic. The Controller (often a Servlet) handles request processing and coordinates between Model and View.

JSP translation refers to the process where the JSP container converts the JSP file into a corresponding Servlet source code. This generated servlet is then compiled. The servlet handles requests by generating HTML output. Option A is wrong because JSP uses its own parser, not generic XML. Option B is wrong because JSP becomes dynamic servlet code, not static HTML.

J2EE supports multiple client types for accessing enterprise applications. Applets are client-side Java programs that run in browsers. Web browsers are the most common J2EE clients using HTTP. Wireless clients include mobile devices and PDAs that access J2EE applications through WAP or similar protocols. Since all three are valid J2EE client types, option D is correct.

JSP (JavaServer Pages) allows embedding Java code directly within the page using scriptlets (<% %>) and expressions (<%= %>). You can write pure Java code including variable declarations, method calls, control flow statements, and expressions. The JSP container translates this Java code into servlet code during compilation.

The statement is false because while HTTP-based servlets extend HttpServlet, the Servlet API also supports generic servlets that extend javax.servlet.GenericServlet. GenericServlet is protocol-independent and can be used for any protocol, not just HTTP. HttpServlet specifically handles HTTP requests and responses.

The JSP translation to servlet happens only once when the JSP is first requested or when it has been modified. The web container compiles the JSP into a servlet class and caches it. Subsequent requests execute the already-compiled servlet without retranslation. This makes JSP processing efficient after the initial compilation.

JSP pages can include both other JSP pages and HTML pages. The jsp:include standard action can include any resource, including HTML pages, at runtime. The <%@ include %> directive can include static content like HTML files at translation time. There is no restriction that only JSP pages can be included.

JSP provides four scopes: page scope (default, accessible only within the page), request scope (accessible during the current request), session scope (accessible across multiple requests from the same user session), and application scope (globally accessible across the entire application). Option C correctly lists all four scopes.

The ServletContext interface defines a set of methods that a servlet uses to communicate with its servlet container, offering details about the server environment. It does not contain information specific to individual client requests or sessions.

JSP provides several implicit objects that are automatically available: request (HttpServletRequest), response (HttpServletResponse), session (HttpSession), application (ServletContext), out (JspWriter), pageContext, page, config, and exception. Option C correctly identifies the core implicit objects for request handling and session/application management.

GET method submits form data as part of the URL in the query string, which is visible in browser history, logs, and can be bookmarked - making it insecure for sensitive data. POST method sends data in the request body, which is not visible in the URL and more secure. Additionally, GET has length limitations (URL length restrictions), while POST can send much larger amounts of data.