JDBC数据库编程操作类(适用于MySQL)_MySQL
package com.msit.Uitll;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
/**
* 数据库帮助类 连接MySQL数据库
*
* @author ruanj_000
*
*/
public class SQLHelp {
private static String dirverName = "com.mysql.jdbc.Driver";
private static String url = "jdbc:mysql://127.0.0.1:3306/misidb";
private static String user = "root";
private static String password = "root";
private static Connection connection = null;
// 编写静态代码块(比构造函数加载更快),用来加载驱动类
static {
try {
Class.forName(dirverName);
// 创建连接对象
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
/**
* 获得连接对象
*
* @return
*/
public static Connection getConnection() {
try {
connection = DriverManager.getConnection(url, user, password);
} catch (SQLException e) {
e.printStackTrace();
}
return connection;
}
/**
* 用来执行 添加、删除、修改的sql语句
*
* @param sql
* @return 受影响的行数
*/
public static int ExecuteNonQuery(String sql) {
int num = 0;
Connection conn = getConnection();
Statement sta = null;
try {
sta = conn.createStatement();
} catch (SQLException e) {
e.printStackTrace();
}
try {
num = sta.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
Close(null, sta, conn);
}
return num;
}
/**
* 执行查询语句方法
* @param sql 数据查询SQL脚本语言
* @return 返回结果集
*/
public static ResultSet ExecuteQuery(String sql){
ResultSet rs=null;
Connection con=getConnection();
Statement sta=null;
try {
sta=con.createStatement();
} catch (SQLException e) {
e.printStackTrace();
}
try {
rs=sta.executeQuery(sql);
} catch (SQLException e) {
e.printStackTrace();
}
finally{
//Close(rs, sta, con);
}
return rs;
}
/**
* 关闭资源的方法
*
* @param rs
* 结果集
* @param sta
* 执行对象
* @param conn
* 连接对象
*/
private static void Close(ResultSet rs, Statement sta, Connection conn) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
System.out.println("数据结果集关闭异常..!");
e.printStackTrace();
}
}
if (sta != null) {
try {
sta.close();
} catch (SQLException e) {
System.out.println("执行对象关闭异常、、!");
e.printStackTrace();
}
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
System.out.println("数据连接关闭异常、、!");
e.printStackTrace();
}
}
rs=null; sta=null; conn=null;
}
/**
* 执行预编译sql语句的方法
* @param sql
* @param prgm
* @return
*/
public static int pstm(String sql,String prgm[]){
int num=0;
PreparedStatement pstm=null;
try {
pstm =getConnection().prepareStatement(sql);
for (int i =1; i pstm.setString(i, prgm[i-1]);
}
num=pstm.executeUpdate();
pstm.close();
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
return num;
}
}

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