链接数据库增删改通用

实现对SQLServer和MySql数据库通用链接及数据的增删改

我们经常需要和数据库打交道，对数据库数据进行增改删查的操作，首先我们必须要先链接数据库，然后对数据内容进行相关增删改操作。

首先看一下目录结构
在这里插入图片描述
程序解读：一共有三个子包分别为model包test包和util包
@：model包是数据信息的类
@@：test包是对数据进行查询获取内容
@@@：util包里的DBUtil是对数据库进行链接和增删改操作的内容，info文件是数据库的相关信息包括，url,name和pwd等

下面向大家展示代码

util包的DBUtil.java

package com.util;import java.io.IOException;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;/** 通用增删改！！！！！！！！！！！！！！* 数据库驱动* 张叔行*/
public class DBUtil {public DBUtil() {System.out.println("启动jdbc");}/*** 定义变量*/private static String driver = null;//驱动private static String url    = null;//mysql链接private static String name   = null;//数据库链接账户private static String pwd    = null;//数据库链接密码/*** 定义静态代码块*/static {Properties porperties = new Properties();//java 的配置文件try {porperties.load(DBUtil.class.getResourceAsStream("info.properties"));driver = porperties.getProperty("driver");url = porperties.getProperty("url");name = porperties.getProperty("name");pwd = porperties.getProperty("pwd");} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}/*** 链接数据库*/public static Connection getConn() {Connection conn  = null;try {Driver.class.forName(driver);conn = DriverManager.getConnection(url,name,pwd);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}System.out.println("数据库链接成功");return conn;}/*** 关闭数据库*/public static void setClose(Connection conn,PreparedStatement ps , ResultSet rs) {try {if(conn != null) {conn.close();}else if(ps != null) {ps.close();}else if(rs != null) {rs.close();}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}/*** 通用增删改*/public static boolean executeUpdate(String sql , Object[] obj) {PreparedStatement ps = null;Connection conn = getConn();Boolean bool   = false;int rsInt = 0;try {sql = "insert into user(u_id,u_name,u_sex,u_phone,u_money,u_map) values(?,?,?,?,?,?)";ps = conn.prepareStatement(sql);for(int i = 0;i<obj.length;i++) {ps.setObject(i+1, obj[i]);}rsInt = ps.executeUpdate();if(rsInt < 0) {System.out.println("添加失败");bool = false;}else {System.out.println("添加成功");bool = true;}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return bool;}/*** 通用查通用查不能用list指定的返回类型要是通用的ResultSet来返回* 通用指的是任何查询都能用*/public static ResultSet executeSelect(String sql , Object[] obj) {Connection conn = getConn();PreparedStatement ps = null;ResultSet rs = null;try {ps = conn.prepareStatement(sql);//如果object的值不等于空来执行这一句话if( obj != null) {for(int i = 0;i<obj.length;i++) {ps.setObject(i+1, obj[i]);}}rs = ps.executeQuery();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return rs;}
}

util包里的info文件：

特别注意：此处是实现对不同数据库链接及增删改操作的重要部分，***链接不同的数据库要修改相对应的url,name和pwd***，修改了之后就可以实现对SQLServer或者MySql数据库等的链接及增删改操作了。

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/log?useUnicode=true&characterEncoding=utf8
name=root
pwd=root

test包里的test.java

package com.test;import com.util.DBUtil;import java.sql.ResultSet;
import java.sql.SQLException;public class test {public static void main(String[] args) {// TODO Auto-generated method stub//通用的增删改String sql = "select * from user where u_name = ?";Object obj[] = {"hwl"};ResultSet selectS  = DBUtil.executeSelect(sql, obj);try {while(selectS.next()) {System.out.println(selectS.getString(1)+"\t"+selectS.getString(2)+"\t"+selectS.getString(3)+"\t"+selectS.getInt(4)+"\t"+selectS.getString(5)+"\t"+selectS.getString(6));}} catch (SQLException e) {e.printStackTrace();}}}

model包里的user.java

package com.model;public class user {private static String UId;private static String UName;private static String USex;private static String UPhone;private static int    UMoney;private static String UMap;public static String getUId() {return UId;}public static void setUId(String uId) {UId = uId;}public static String getUName() {return UName;}public static void setUName(String uName) {UName = uName;}public static String getUSex() {return USex;}public static void setUSex(String uSex) {USex = uSex;}public static String getUPhone() {return UPhone;}public static void setUPhone(String uPhone) {UPhone = uPhone;}public static int getUMoney() {return UMoney;}public static void setUMoney(int uMoney) {UMoney = uMoney;}public static String getUMap() {return UMap;}public static void setUMap(String uMap) {UMap = uMap;}}