package com.etc.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

/** 数据库访问基础类 */

public class BaseDao {

//String driver="com.mysql.cj.jdbc.Driver"; //mysql8

//String url="jdbc:mysql://localhost:3306/iotdemo?characterEncoding=utf8&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true";//mysql8

String driver="com.mysql.jdbc.Driver"; //mysql5

String url="jdbc:mysql://localhost:3306/myjob";//mysql5

String user="root";

String password="root";

/**

* 获得数据库连接

*

* @return 数据库连接对象

*/

public Connection getConnection() {

Connection conn = null;// 数据库连接对象

if (conn == null) {

try {

Class.forName(driver);// 加载驱动

conn = DriverManager.getConnection(url, user, password);// 建立连接

} catch (ClassNotFoundException e) {

e.printStackTrace();

} catch (SQLException e) {

e.printStackTrace();

}

}

return conn;

}

/**

* 关闭资源

*/

public void closeAll(ResultSet rs, PreparedStatement ps, Connection conn) {

try {

if (rs != null) {

rs.close();

}

if (ps != null) {

ps.close();

}

if (conn != null) {

conn.close();

}

} catch (SQLException e) {

e.printStackTrace();

}

}

/**

* 增删改通用方法

*

* @param sql

* 执行增删改的SQL语句

* @param args

* 参数数组

* @return 受影响行数

*/

public int executeUpdate(String sql, Object... args) {

int result = -1;

PreparedStatement ps = null;// 预编译对象

Connection conn = this.getConnection();

try {

ps = conn.prepareStatement(sql);

if (args != null) {

for (int i = 0; i < args.length; i++) {

ps.setObject(i + 1, args[i]);

}

}

result = ps.executeUpdate();// 执行增删改

} catch (SQLException e) {

e.printStackTrace();

} finally {

this.closeAll(null, ps, conn);

}

return result;

}

}