JSP Elements

JSP Elements

JSP page is converted to Servlet java class. Therefore following elements in JSP will be copied in Servelet. Suppose there is a JSP page named "DisplayCounter.jsp". It will be converted to DisplayCounter_jsp class when it is placed in container. DisplayCounter_jsp will be extended from HttpServlet. Inside this class _jspService() method will be created and all the java code will be populated there.

• Directives
  Page directive
  <%@ page import="java.util.*" %>
  Page directive defines page-spacific properties such as character encoding, the content type, whether this page should have the implicit session object.
  Attributes in page directives are
  • import
  • isThreadSafe
  • contentType
  • isELIgnored
  • isErrorPage
  • errorPage
  Taglib directive
  <%@ taglib tagdir="/WEB-INF/tags/cool" prefix="cool" %>
  It defines tag libraries available to the JSP.
  Include directive
  <%@ include file="wickedHeader.html" %>
  It defines text and code that gets added into the current page at translation time. This lets you build reusable chunks withou having to duplicate all that code in each JSP.
• Declaration
  <%! int count=0; %>
  Declare count will be a member variable. You can define method or member variable.
• Scriptlet
  <% out.println(count); %>
  Inside the scriptlet, you can write java code which will be copeid to converted servelet.
• Expression
  <%=count+1 %>
• Jsp Comment
  `<%-- --%>