JQuery用户名校验的具体实现

$.get("http://localhost:8080/JQueryStudy/UserVerify?userName=" + encodeURI(encodeURI(userName)),null,
          function(response){
            $("#result").html(response);
          }
        )

/
  To change this template, choose Tools | Templates
  and open the template in the editor.
 /

package .linying;

import java.io.IOException;
import java.io.PrintWriter;
import java..URLDecoder;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/
  用户名验证Servlet
  @author Ying-er
  @time 2010-4-25下午08:02:08
  @version 1.0
 /
public class UserVerify extends HttpServlet {
  
  / 
   Processes requests for both HTTP <code>GET</code> and <code>POST</code> methods.
   @param request servlet request
   @param response servlet response
  /
  protected void processRequest(HttpServletRequest request, HttpServletResponse response)
  throws ServletException, IOException {
    response.setContentType("text/html;charset=UTF-8");
    PrintWriter out = response.getWriter();
    try {
      String param = request.getParameter("userName");
      if (param == null || param.length() == 0) {
        out.println("用户名不能为空");
      } else {
        String userName = URLDecoder.decode(param, "UTF-8");
        System.out.println(userName);
        if (userName.equals("Ying-er")) {
          out.println("用户名[" + userName + "]已经存在，请使用别的用户名注册");
        } else {
          out.println("可以使用用户名[" + userName + "]注册");
        }
      }
    } finally { 
      out.close();
    }
  } 

  // <editor-fold defaultstate="collapsed" desc="HttpServlet">
  / 
   Handles the HTTP <code>GET</code> method.
   @param request servlet request
   @param response servlet response
  /
  protected void doGet(HttpServletRequest request, HttpServletResponse response)
  throws ServletException, IOException {
    processRequest(request, response);
  } 

  / 
   Handles the HTTP <code>POST</code> method.
   @param request servlet request
   @param response servlet response
  /
  protected void doPost(HttpServletRequest request, HttpServletResponse response)
  throws ServletException, IOException {
    processRequest(request, response);
  }

  / 
   Returns a short description of the servlet.
  /
  public String getServletInfo() {
    return "Short description";
  }// </editor-fold>

}