JSP pageContext object and config object

a pageContext object

 

 

Two common methods of pageContext object

 

 

Three pageContext method tests

Code 1:

<%@ page language = "java" import = "java.util.*,java.text.*" contentType = "text/html; charset=utf-8" %>

<%

String path = request.getContextPath();

String basePath = request.getScheme()+ "://" +request.getServerName()+ ":" +request.getServerPort()+path+ "/" ;

%>

 

<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

< html >

  < head >

    < base href = " <%= basePath %> " >

   

    < title > My JSP 'index.jsp' starting page </ title >

         < meta http-equiv = "pragma" content = "no-cache" >

         < meta http-equiv = "cache-control" content = "no-cache" >

         < meta http-equiv = "expires" content = "0" >    

         < meta http-equiv = "keywords" content = "keyword1,keyword2,keyword3" >

         < meta http-equiv = "description" content = "This is my page" >

         <!--

        <link rel =" stylesheet " type="text/ css " href ="styles.css">

        -->

  </ head >

 

  < body >

    < h1 > session built-in object </ h1 >

    < hr >

    <%

      SimpleDateFormat sdf = new SimpleDateFormat( "yyyy year MM month dd day HH:mm:ss" );

      Date d = new Date(session.getCreationTime());

      session.setAttribute( "username" , "admin" );

      session.setAttribute( "password" , "123456" );

      session.setAttribute( "age" , 20);

     

      //Set the maximum generation period of the current session in seconds

      //session.setMaxInactiveInterval(10);//10 seconds

     

    %>

    Session creation time: <%= sdf.format(d) %> < br >    

    Session的ID编号： <%= session.getId() %> < BR >

         Get username from Session: <%= session.getAttribute( "username" ) %> < br >

        

    < a href = "session_page2.jsp" target = "_blank" > 跳转到Session_page2. jsp </ a >     

       

  </ body >

</ html >

Code 2:

<%@ page language = "java" import = "java.util.*,java.text.*" contentType = "text/html; charset=utf-8" %>

<%

 String path = request.getContextPath();

 String basePath = request.getScheme()+ "://" +request.getServerName()+ ":" +request.getServerPort()+path+ "/" ;

 Date date = new Date();

 SimpleDateFormat sdf = new SimpleDateFormat( "MM, MM, DD, YYYY" );

 String s = sdf.format(date);

 out.println(s+ "<br>" );

%>

Code 3:

<%@ page language = "java" import = "java.util.*" contentType = "text/html; charset=utf-8" %>

<%

String path = request.getContextPath();

String basePath = request.getScheme()+ "://" +request.getServerName()+ ":" +request.getServerPort()+path+ "/" ;

%>

 

<! DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

< html >

  < head >

    < base href = " <%= basePath %> " >

   

    < title > My JSP 'index.jsp' starting page </ title >

         < meta http-equiv = "pragma" content = "no-cache" >

         < meta http-equiv = "cache-control" content = "no-cache" >

         < meta http-equiv = "expires" content = "0" >    

         < meta http-equiv = "keywords" content = "keyword1,keyword2,keyword3" >

         < meta http-equiv = "description" content = "This is my page" >

         <!--

        <link rel =" stylesheet " type="text/ css " href ="styles.css">

        -->

  </ head >

 

  < body >

    < h1 > pageContext built-in object </ h1 >

    < hr >    

        用户名是： <%= pageContext.getSession().getAttribute( "username" ) %> < br >      

    <%

       // Jump to the registration page

       //pageContext.forward("reg.jsp");

       pageContext.include( "include.jsp" );

    %>                

  </ body >

</ html >

Validation results:

 

 

Four config objects