JDBC连接数据库

JDBC连接数据库

  连接mysql必导包【mysql-connector-java-5.1.47.jar】

  这里提供了连接mysql相关jar包的所有版本： https://mvnrepository.com/artifact/mysql/mysql-connector-java

相关配置文件：（jdbc.properties）

# 加载驱动
jdbc.driver=com.mysql.jdbc.Driver
# 注册驱动
jdbc.url=jdbc:mysql://localhost:3306/stmng?useUnicode=true&characterEncoding=utf8&useSSL=true
# 连接数据库的用户名
jdbc.user=root
# 连接数据库的密码
jdbc.password=root

JDBC连接工具类

package com.lyang.util;

import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;

/**
 * jdbc连接工具类
 */
public class JDBCUtil {
	
	  private static final String DRIVER;
	  private static final String URL; 
	  private static final String USER;
	  private static final String PASSWORD;
	 
	static {
		InputStream ips = null;
		Properties prop = null;
		try {
			// 加载配置文件
			ips = JDBCUtil.class.getClassLoader().getResourceAsStream("jdbc.properties");
			prop = new Properties();
			prop.load(ips);
		} catch (IOException e) {
			e.printStackTrace();
		}
		DRIVER = prop.getProperty("jdbc.driver");
		URL = prop.getProperty("jdbc.url");
		USER = prop.getProperty("jdbc.user");
		PASSWORD = prop.getProperty("jdbc.password");
		// 加载驱动
		try {
			Class.forName(DRIVER);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 获取连接
	 * @return
	 */
	public static Connection getConn() {
		Connection conn = null;
		try {
			conn = DriverManager.getConnection(URL, USER, PASSWORD);
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return conn;
	}
	
	/**
	 * 释放资源
	 * @param conn
	 * @param prep
	 */
	public static void close(Connection conn, PreparedStatement prep) {
		try {
			if (null != conn) {
				conn.close();
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
		try {
			if (null != prep) {
				prep.close();
			}
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void close(Connection conn,PreparedStatement prep,ResultSet rs) {
		try {
			if (null!=rs) {
				rs.close();
			}
			close(conn, prep);
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}
	
	public static void main(String[] args) {
		System.out.println(getConn());
	}
	
}