JSP application object

an introduction

 

 

Two common methods

 

 

Three examples

<%@ 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 > application built-in objects </ h1 >

    <%

       application.setAttribute( "city" , "北京" );

       application.setAttribute( "postcode" , "10000" );

       application.setAttribute( "email" , " [email protected] " );

      

    %>

         The city is: <%= application.getAttribute( "city" ) %> < br >

    The attributes in the application are: <%

         Enumeration attributes = application.getAttributeNames();

         while (attributes.hasMoreElements())

         {

            out.println(attributes.nextElement()+ "  " );

         }

    %> < br >

    JSP (SERVLET) engine name and version number: <%= application.getServerInfo() %> < br >              

                  

  </ body >

</ html >

 

Four running results