jdbc-获取连接的五种方式

package JDBCTest;

import org.junit.jupiter.api.Test;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

import static org.junit.jupiter.api.Assertions.*;

class ConnectionTestTest {
    @Test
    public void test5() throws  Exception{
        //final version  
        InputStream resourceAsStream = ConnectionTestTest.class.getClassLoader().getResourceAsStream("jdbc.properties");
        Properties properties = new Properties();
        properties.load(resourceAsStream);
        String user = properties.getProperty("user");
        String password = properties.getProperty("password");
        String url = properties.getProperty("url");
        String driverClass = properties.getProperty("driverClass");
        Class.forName(driverClass);
        Connection connection = DriverManager.getConnection(url, user, password);
        System.out.println(connection);
        resourceAsStream.close();


    }
    @Test
    public void test4() throws  Exception{
        String user = "root";
        String password = "110120";
        String url = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8";
        Class.forName("com.mysql.jdbc.Driver");//driver 有静态代码块  会自动加载

        Connection connection = DriverManager.getConnection(url,user,password);
        System.out.println(connection);
    }
    @Test
    public void test3() throws  Exception{
        Class<?> aClass = Class.forName("com.mysql.jdbc.Driver");
        Driver driver = (Driver) aClass.newInstance();
        //获取driver的实例化对象

        try {
            DriverManager.registerDriver(driver);
        } catch (SQLException throwables) {
            throwables.printStackTrace();
        }
        String user = "root";
        String password = "110120";
        String url = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8";
        Connection connection = DriverManager.getConnection(url,user,password);
        System.out.println(connection);
    }
    @Test
    public void test2() throws Exception{
        //获取方拾贰//为了不出现sun公司的第三方类
        Class<?> aClass = Class.forName("com.mysql.jdbc.Driver");
        Driver driver = (Driver) aClass.newInstance();
        //提供需要连接的数据库
        String url = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8";
        Properties info = new Properties();
        info.setProperty("user","root");
        info.setProperty("password","110120");
        Connection connect = driver.connect(url, info);
        System.out.println(connect);
    }

    @Test
    public void test1() throws SQLException {
        //方式一
        Driver driver = new com.mysql.jdbc.Driver();
        String url = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8";
        Properties info = new Properties();
        info.setProperty("user","root");
        info.setProperty("password","110120");
        Connection connect = driver.connect(url, info);
        System.out.println(connect);

    }A

}