如何使用AJAX—III

package ajax;

import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

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

import com.alibaba.fastjson.JSON;

public class myServlet extends HttpServlet {

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		OutputStream out = resp.getOutputStream();

//		out.write("hell world!".getBytes());
		Map map=new HashMap();
		map.put("name", "小名");
		map.put("age",18);
		map.put("sex", "男");
		Object obj=JSON.toJSON(map);
		out.write(obj.toString().getBytes());
		out.close();
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		super.doPost(req, resp);
	}

}

package com.cvs.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import com.cvs.model.User;
import com.cvs.util.DBUtil;

public class UserDao {
	public List<User> findAllUsers() {
		List list = new ArrayList();

		Connection conn = DBUtil.getConnection();
		try {
			PreparedStatement ps = conn.prepareStatement("select * from user ");
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				User user = new User();
				user.setName("");
				user.setPassword("");
				String name = rs.getString("username");
				String password = rs.getString("password");
				user.setName(name);
				user.setPassword(password);
				list.add(user);
			}
			rs.close();
			ps.close();

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {// 無論有沒有異常都會執行
			DBUtil.closeConn();
		}
		return list;
	}

	public User findUserByName(String username) {
		User user = new User();
		user.setName("");
		user.setPassword("");
		Connection conn = DBUtil.getConnection();
		try {
			PreparedStatement ps = conn
					.prepareStatement("select * from user where username=?");
			ps.setString(1, username);
			ResultSet rs = ps.executeQuery();
			while (rs.next()) {
				String name = rs.getString("username");
				String password = rs.getString("password");
				user.setName(name);
				user.setPassword(password);
			}
			rs.close();
			ps.close();

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {// 無論有沒有異常都會執行
			DBUtil.closeConn();
		}
		return user;
	}

	public Boolean addUser(User user) {
		Connection conn = DBUtil.getConnection();
		boolean flg = false;
		try {
			PreparedStatement ps = conn
					.prepareStatement("insert into user(username,password,sex,hometown,birthday,ismery,address) value (?,?,?,?,?,?,?)");
			ps.setString(1, user.getName());
			ps.setString(2, user.getPassword());
			ps.setString(3, user.getSex());
			ps.setString(4, user.getHometown());
			ps.setString(5, user.getBirthday());
			ps.setString(6, user.getSex());
			ps.setString(7, user.getAddress());
			flg = ps.execute();
			ps.close();

		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			DBUtil.closeConn();
		}

		return true;
	}
}

package com.cvs.model;

public class User {

	private int id;
	private String name;
	private String password;
	private String sex;
	private String birthday;
	private String hometown;
	private String address;//現在住址
	private String isMer;
	
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getIsMer() {
		return isMer;
	}
	public void setIsMer(String isMer) {
		this.isMer = isMer;
	}
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public String getBirthday() {
		return birthday;
	}
	public void setBirthday(String birthday) {
		this.birthday = birthday;
	}
	public String getHometown() {
		return hometown;
	}
	public void setHometown(String hometown) {
		this.hometown = hometown;
	}
	@Override
	public String toString() {
		return "User [id=" + id + ", name=" + name + ", password=" + password + ", sex=" + sex + ", birthday="
				+ birthday + ", hometown=" + hometown + "]";
	}
	
}

package com.cvs.servlert;

import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

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

import com.alibaba.fastjson.JSON;
import com.cvs.dao.UserDao;
import com.cvs.model.User;

public class LoginServlert extends HttpServlet{

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		String username=req.getParameter("username");
		String password=req.getParameter("password");
		UserDao userDao=new UserDao();
		User user=userDao.findUserByName(username);
    	Map map=new HashMap();

        if (null!=user&&user.getName().equals(username)&&user.getPassword().equals(password)){
        	map.put("status", 1);
        	map.put("msg", "登錄成功！");

        }else{
        	map.put("status", 0);
        	map.put("msg", "登錄失敗！！！");
        	
        }
			OutputStream out= resp.getOutputStream();
			String json= JSON.toJSONString(map);
			out.write(json.getBytes());
			out.close();
	}
		


	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		super.doPost(req, resp);
	}

}

package com.cvs.util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DBUtil {

	private static Connection conn=null;
	//打開鏈接
	public static Connection getConnection () {
		//加載驅動
		try {
			Class.forName("com.mysql.jdbc.Driver");//加載驅動
			conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/qqs", "root", "123456");//獲取連接
			
			
		} catch (ClassNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return conn;
	}
	//關閉鏈接
	public static void closeConn() {
		if(null!=conn) {
			try {
				conn.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
	}
}

<%@ page language="java" import="java.util.*" pageEncoding="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%>">
    <script type="text/javascript" src="js/jquery.js"></script>
    <title>My JSP 'index.jsp' starting page</title>
	
  </head>
  
  <body>
   <input type="text" id="context"><span id="sp1">請輸入用戶名</span>
  </body>
  <script type="text/javascript">
$("#context").blur(function(){
$("#b001").click(function(){
   $.ajax(
   {
   url:"asd",
   success:function(data){
   $("#sp1").text(data);
   }
   }
   );
});
})



/*$("#b001").click(function(){
   $.ajax(
   {
   url:"abc.html",
   success:function(data){
   $("#myid").html(data);
   }
   }
   );
});*/
</script>
<html>

<%@ page language="java" import="java.util.*" pageEncoding="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 'login.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">
	-->
		<script type="text/javascript" src="js/jquery.js">
</script>
	</head>

	<body>
		<form action="">
			<input name="username" id="username" type="text">
			<input name="password" id="password" type="password">
			<input type="button" id="b001" value="登錄">

		</form>
		<script type="text/javascript">
$("#b001").click(function() {
	var username = $("#username").val();
	var password = $("#password").val();
	$.ajax( {
		url : "login",
		dataType : "json",
		data : {
			"username" : username,
			"password" : password
		},
		success : function(data) {
			alert(data.status);
			window.location.href = "success.jsp";
		}
	});
});
</script>
	</body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="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 'success.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>
 登錄成功！！！
  </body>
</html>

web.xml

package com.cvs.servlert;

import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

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

import com.alibaba.fastjson.JSON;
import com.cvs.dao.UserDao;
import com.cvs.model.User;

public class FindUsersServlet extends HttpServlet{

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		OutputStream out= resp.getOutputStream();
		Map map=new HashMap();
		UserDao userDao =new UserDao();
		List<User> users=userDao.findAllUsers();
		map.put("list", users);
		map.put("status", 1);
		out.write(JSON.toJSONString(map).getBytes());
		out.close();
	}

	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		super.doPost(req, resp);
	}
	

}

package com.cvs.servlert;

import java.io.IOException;
import java.io.OutputStream;
import java.util.HashMap;
import java.util.Map;

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

import com.alibaba.fastjson.JSON;
import com.cvs.dao.UserDao;
import com.cvs.model.User;

public class LoginServlert extends HttpServlet{

	@Override
	protected void doGet(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		String username=req.getParameter("username");
		String password=req.getParameter("password");
		UserDao userDao=new UserDao();
		User user=userDao.findUserByName(username);
    	Map map=new HashMap();

        if (null!=user&&user.getName().equals(username)&&user.getPassword().equals(password)){
        	map.put("status", 1);
        	map.put("msg", "登錄成功！");

        }else{
        	map.put("status", 0);
        	map.put("msg", "登錄失敗！！！");
        	
        }
			OutputStream out= resp.getOutputStream();
			String json= JSON.toJSONString(map);
			out.write(json.getBytes());
			out.close();
	}
		


	@Override
	protected void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		// TODO Auto-generated method stub
		super.doPost(req, resp);
	}

}

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
	<welcome-file-list>
		<welcome-file>index.jsp</welcome-file>
	</welcome-file-list>
	<servlet>
		<servlet-name>abc</servlet-name>
		<servlet-class>ajax.myServlet</servlet-class>

	</servlet>
	<servlet-mapping>
		<servlet-name>abc</servlet-name>
		<url-pattern>/asd</url-pattern>
	</servlet-mapping>


	<servlet>
		<servlet-name>login</servlet-name>
		<servlet-class>com.cvs.servlert.LoginServlert</servlet-class>

	</servlet>
	<servlet>
		<description>This is the description of my J2EE component</description>
		<display-name>This is the display name of my J2EE component</display-name>
		<servlet-name>FindUsersServlet</servlet-name>
		<servlet-class>com.cvs.servlert.FindUsersServlet</servlet-class>
	</servlet>

	<servlet-mapping>
		<servlet-name>login</servlet-name>
		<url-pattern>/login</url-pattern>
	</servlet-mapping>
	<servlet-mapping>
		<servlet-name>FindUsersServlet</servlet-name>
		<url-pattern>/servlet/FindUsersServlet</url-pattern>
	</servlet-mapping>


	<servlet>
		<servlet-name>users</servlet-name>
		<servlet-class>com.cvs.servlert.FindUsersServlet</servlet-class>

	</servlet>
	<servlet-mapping>
		<servlet-name>users</servlet-name>
		<url-pattern>/users</url-pattern>
	</servlet-mapping>


</web-app>