JDBC查询数据返回给jsp页面(注解方式完成)

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所需要jar包：

mysql图表

eclipse框架

input.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"

pageEncoding="ISO-8859-1"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">

<title>Insert title here</title>

</head>

<body>

<form id="myForm">

ID:<input type="text" name="id" /> <input type="button"

value="submit" id="btn">

</form>

</body>

<script>

var oBtn = document.getElementById("btn");

oBtn.onclick = function() {//js点击事件

var oInput = document.getElementsByTagName("input")[0];

var id = oInput.value;

location.href = "/jdbc/Servlet?id=" + id;

}

/* oBtn.onclick = function(){

document.getElementById("myForm").submit();

} */

</script>

</html>

return.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

pageEncoding="UTF-8"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

</head>

<body>

<div>姓名：${map.Id}</div>

<div>年龄：${map.Name}</div>

<div>年龄：${map.Sex}</div>

<div>年龄：${map.Age}</div>

</body>

</html>

Jdbc.java

package com.jdbc;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.HashMap;

import java.util.Map;

public class Jdbc {

// 声明Connection对象

java.sql.Connection con;

// 驱动程序名

String driver = "com.mysql.jdbc.Driver";

// URL指向要访问的数据库名mydata

String url = "jdbc:mysql://localhost:3306/testmysql";

// MySQL配置时的用户名

String user = "root";

// MySQL配置时的密码

String password = "root";

// 结果集

java.sql.ResultSet rs;

java.sql.Statement statement = null;

public Map<String, Object> get(String userId) {

// 遍历查询结果集

try {

// 加载驱动程序

Class.forName(driver);

// 1.getConnection()方法，连接MySQL数据库！！

con = DriverManager.getConnection(url, user, password);

// 2.创建statement类对象，用来执行SQL语句！！

statement = con.createStatement();

// 要执行的SQL语句

String sql = "SELECT * FROM student WHERE Id=" + userId;

// 3.ResultSet类，用来存放获取的结果集！！

rs = statement.executeQuery(sql);

Map<String, Object> m = null;

while (rs.next()) {

String Id = rs.getString("Id");

String Name = rs.getString("Name");

String Sex = rs.getString("Sex");

String Age = rs.getString("Age");

m = new HashMap<String, Object>();

m.put("Id", Id);

m.put("Name", Name);

m.put("Sex", Sex);

m.put("Age", Age);

}

return m;

} catch (Exception e) {

System.out.println("Sorry,can`t find the Driver!");

} finally {

try {

rs.close();

} catch (SQLException e) {

e.printStackTrace();

}

try {

statement.close();

} catch (SQLException e1) {

e1.printStackTrace();

}

try {

con.close();

} catch (SQLException e) {

e.printStackTrace();

}

}

return null;

}

}

Servlet.java

package com.jdbc;

import java.io.IOException;

import java.util.Map;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

@WebServlet("/Servlet")

public class Servlet extends HttpServlet {

private static final long serialVersionUID = 1L;

protected void service(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException {

String userId = request.getParameter("id");

Map<String, Object> map = new Jdbc().get(userId);

request.setAttribute("map", map);

request.getRequestDispatcher("/return.jsp").forward(request,response);

}

}

测试结果

主要是主要这里面的数据怎么传的，先是从input获得查询条件——提交到servlet中——jdbc调取mysql中的数据——return反馈给用户查询结果

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