Java连接Mysql数据库的五种方法

说明: 本文通过maven构建,连接的数据库是mysql 数据库

pom.xml

 <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.38</version>
    </dependency>

数据库连接方式一

 public static void Connection1() throws SQLException {
        Driver drive=new com.mysql.jdbc.Driver();
        String  url="jdbc:mysql://localhost:3306/test";
        Properties info=new Properties();
        info.setProperty("user","root");
        info.setProperty("password","root");
        Connection connect = drive.connect(url, info);
        System.out.println(connect);
    }

数据库连接方式二

 public static void Connection2() throws ClassNotFoundException, InstantiationException, IllegalAccessException, SQLException {
        // 1.获取Driver实现类对象：使用反射
        Class clazz = Class.forName("com.mysql.jdbc.Driver");
        Driver driver = (Driver) clazz.newInstance();
        // 2.提供要连接的数据库
        String url = "jdbc:mysql://localhost:3306/test";
        // 3.提供连接需要的用户名和密码
        Properties info = new Properties();
        info.setProperty("user", "root");
        info.setProperty("password", "root");
        // 4.获取连接
        Connection conn = driver.connect(url, info);
        System.out.println(conn);
    }

 

数据库连接方式三

 // 1.获取Driver实现类的对象
        Class clazz = Class.forName("com.mysql.jdbc.Driver");
        Driver driver = (Driver) clazz.newInstance();
        // 2.提供另外三个连接的基本信息：
        String url = "jdbc:mysql://localhost:3306/test";
        String user = "root";
        String password = "root";
        // 注册驱动
        DriverManager.registerDriver(driver);
        // 获取连接
        Connection conn = DriverManager.getConnection(url, user, password);
        System.out.println(conn);

 

数据库连接方式四

String url = "jdbc:mysql://localhost:3306/test";
        String user = "root";
        String password = "root";

        // 2.加载Driver
        Class.forName("com.mysql.jdbc.Driver");
        // 3.获取连接
        Connection conn = DriverManager.getConnection(url, user, password);
        System.out.println(conn);

 

数据库连接方式五 非常推荐使用

好处:

• 1.实现了数据与代码的分离。实现了解耦

• 2.如果需要修改配置文件信息，可以避免程序重新打包。

user=root
password=root
url=jdbc:mysql://localhost:3306/test?rewriteBatchedStatements=true
driverClass=com.mysql.jdbc.Driver

        InputStream is = connDate.class.getClassLoader().getResourceAsStream("jdbc.properties");
        Properties pros = new Properties();
        pros.load(is);
        String user = pros.getProperty("user");
        String password = pros.getProperty("password");
        String url = pros.getProperty("url");
        String driverClass = pros.getProperty("driverClass");
        //2.加载驱动
        Class.forName(driverClass);
        //3.获取连接
        Connection conn = DriverManager.getConnection(url, user, password);
        System.out.println(conn);