只是用单纯的 servlet+jsp+ajax+json+mysql+jstl+jquery 做一个小测试
package Servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import Dao.UserDao;
import Dao.UserinfoDao;
import Entity.User;
import Page.PageUtil;
/**
* Servlet implementation class ServletLogin_JSON
*/
@WebServlet("/ServletLogin_JSON")
public class ServletLogin_JSON extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public ServletLogin_JSON() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doPost(request,response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
// 用来测试下 servlet ajax json 交互数据
System.out.println("进入了ServletLogin_JSON...");
response.setCharacterEncoding("UTF-8");
request.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");
PrintWriter print = response.getWriter();// 返回 json 类型数据的
UserDao userDao = new UserDao();
System.out.println("创建了UserDao对象...");
User user = new User();
HttpSession session = request.getSession();
String data = null;
String username = request.getParameter("UN");
String password = request.getParameter("PS");
user.setUsername(username);
user.setPassword(password);
try {
int flag = userDao.loginUser(user);
if(flag == 1){
data = "no_username";
print.print(data);// 以返回一个字符串，json形式
}
if(flag == 2){
data = "error_password";
print.print(data);
}
if(flag == 3){
data = "success";
print.print(data);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}