本文实例讲述了jquery访问servlet并返回数据到页面的方法。分享给大家供大家参考。具体实现方法如下：

1. servlet:AjaxServlet.java如下：

import java.io.IOException; 
import java.io.PrintWriter; 
import java.net.URLDecoder; 

import javax.servlet.ServletException; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 

public class AjaxServlet extends HttpServlet { 
    private static final long serialVersionUID = 1L; 
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) 
            throws ServletException, IOException { 
        Integer total = (Integer) req.getSession().getAttribute(\"total\"); 
        int temp = 0; 
        if(total == null ){ 
            temp = 1; 
        }else{ 
            temp = total.intValue() + 1; 
        } 
    req.getSession().setAttribute(\"total\",temp); 
        try { 
            //1.取参数 
            resp.setContentType(\"text/html;charset=GBK\"); 
            PrintWriter out = resp.getWriter(); 
            String old = req.getParameter(\"name\"); 
            //2.检查参数是否有问题 
            //String name = new String(old.getBytes(\"iso8859-1\"),\"UTF-8\"); 
            String name = URLDecoder.decode(old,\"UTF-8\"); 
            if(\"\".equals(old) || old == null){ 
                out.println(\"用户名必须输入\"); 
            }else{ 
                if(\"liling\".equals(name)){ 
                    out.println(\"恭喜登录成功\"); 
                    return; 
                }else{ 
                    out.println(\"该用户名未注册，您可以注册[\"+name+\"]这个用户名\"+temp); 
                } 
            } 
        } catch (Exception e) { 
            // TODO Auto-generated catch block 
            e.printStackTrace(); 
        } 
        //3.检验操作 
    } 
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) 
            throws ServletException, IOException { 
        doGet(req, resp); 
    } 
}