Java连接MySql数据库

读取属性文件的类:

package com.lxf.jdbc;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class LoadConfig {

    private static Properties prop = new Properties();
    private static LoadConfig instance = new LoadConfig();

    // 读取属性文件
    private LoadConfig() {
	InputStream in =    this.getClass().getResourceAsStream("db.properties");
	try {
	    prop.load(in);
	} catch (IOException e) {
	    e.printStackTrace();
	}
    }
    //单列
    public static LoadConfig getInstance() {
	return instance;
    }

    // 获取对应属性的值
    public String getProperty(String key) {
	return (String) prop.get(key);
    }

}

连接数据库工具类：

package com.lxf.jdbc;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public final class JdbcUtils {
    
    private static LoadConfig lo = LoadConfig.getInstance();
    private static String driverClass = lo.getProperty("driverClass");
    private static String url = lo.getProperty("url");
    private static String user = lo.getProperty("username");
    private static String password = lo.getProperty("password");

    private JdbcUtils() {
    }
    
    // 静态代码块，只加载一次
    static {
	try {
	    Class.forName(driverClass);
	} catch (ClassNotFoundException e) {
	    throw new ExceptionInInitializerError(e);
	}
    }

    // 获取链接
    public static Connection getConnection() throws SQLException {
	return DriverManager.getConnection(url, user, password);
    }

    // 关闭数据流
    public static void closeConnection(ResultSet rs, Statement statement,
	    Connection con) {
	try {
	    if (rs != null) {
		rs.close();
	    }
	} catch (SQLException e) {
	    e.printStackTrace();
	} finally {
	    try {
		if (statement != null) {
		    statement.close();
		}
	    } catch (Exception e) {
		e.printStackTrace();
	    } finally {
		try {
		    if (con != null) {
			con.close();
		    }
		} catch (SQLException e) {
		    e.printStackTrace();
		}
	    }
	}
    }

}

属性文件：db.propertise

driverClass=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1/jdbc
user：name=root
password=root

附加Mysql驱动