// instanceconcurrenttest.jsp
<%@ page contentType="text/html;charset=GBK" %>
<%!	
    //定義實(shí)例變量	
    String username;	
    String password;
    java.io.PrintWriter output;
%>
<%	
    //從request中獲取參數(shù)
    username = request.getParameter("username");
    password = request.getParameter("password");
    output = response.getWriter();
    showUserInfo();	
 %>
 <%!	
    public void showUserInfo() {		
       //為了突出并發(fā)問(wèn)題，在這兒首先執(zhí)行一個(gè)費(fèi)時(shí)操作		
       int i =0;		
       double sum = 0.0;		
       while (i++ < 200000000) {
             sum += i;		
       }				
       
       output.println(Thread.currentThread().getName() + "<br>");
       output.println("username:" + username + "<br>");	
       output.println("password:" + password + "<br>");	
    }
 %>

// InstanceConcurrentTest.java
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.PrintWriter;
public class InstanceConcurrentTest extends HttpServlet
 {	
      String username;	
      String password;	
      PrintWriter out;	
      public void doGet(HttpServletRequest request, 
       HttpServletResponse response)          
       throws ServletException,java.io.IOException	
       {		
           //從request中獲取參數(shù)		
	   username = request.getParameter("username");
	   password = request.getParameter("password");	
	   System.out.println(Thread.currentThread().getName() +
	    " | set username:" + username);
	   out = response.getWriter();	
	   showUserInfo();		
       }	
       public void showUserInfo() {		
           //為了突出并發(fā)問(wèn)題，在這兒首先執(zhí)行一個(gè)費(fèi)時(shí)操作		
	   int i =0;		
	   double sum = 0.0;		
	   while (i++ < 200000000) {	
	     sum += i;		
	   }		
	   out.println("thread:" + Thread.currentThread().getName());
	   out.println("username:"+ username);	
	   out.println("password:" + password);	
	}
}

<%@ page contentType="text/html;charset=GBK" %>
<%	
    //使用局部變量
    String username;
    String password;
    java.io.PrintWriter output;
    //從request中獲取參數(shù)
    username = request.getParameter("username");
    password = request.getParameter("password");
    output = response.getWriter();
    showUserInfo(output, username, password);
%>
<%!	
    public void showUserInfo(java.io.PrintWriter _output,
     String _username, String _password) {
    //為了突出并發(fā)問(wèn)題，在這兒首先執(zhí)行一個(gè)費(fèi)時(shí)操作
      int i =0;	
      double sum = 0.0;	
      while (i++ < 200000000) {	
        sum += i;		
      }				
      _output.println(Thread.currentThread().getName() + "<br>");
      _output.println("username:" + _username + "<br>");
      _output.println("password:" + _password + "<br>");
      }
%>