JDBC连接Mysql8

原生方式

public static void main(String[] args) throws Exception{
	jdbc();
}

public static void jdbc() throws Exception {
	final String DRIVER = "com.mysql.cj.jdbc.Driver";
	final String URL = "jdbc:mysql://localhost:3306/myjdbctest?serverTimezone=CST";
	final String USER = "root";
	final String PASS = "w1234";
	String sql = "select username,password from user";
	Connection connection = null;
	PreparedStatement preparedStatement = null;
	ResultSet result=null;
	try {
		Class.forName(DRIVER);
		connection = DriverManager.getConnection(URL, USER, PASS);
		preparedStatement = connection.prepareStatement(sql);
		result = preparedStatement.executeQuery();
		while (result.next()) {
			String str1 = result.getString(1);
            String str2 = result.getString(2);
            System.out.println(str1 + " --- " + str2);
        }
    } catch (Exception e) {
        e.printStackTrace();
   	} finally {
		if (result!=null){
			result.close();
		}
		if (preparedStatement != null) {
			preparedStatement.close();
		}
		if (connection != null) {
			connection.close();
		}
	}
}

连接池druid

配置文件
druid.properties

driverClassName=com.mysql.cj.jdbc.Driver
url=jdbc:mysql://localhost:3306/myjdbctest?serverTimezone=CST
username=root
password=w1234

# 初始化大小
initialSize=5
# 最小空闲数
minIdle=10
# 最大活跃数
maxActive=20
# 获取连接的等待时间
maxWait=10000
# 间隔多长时间  检测是否关闭空闲连接  单位是毫秒
timeBetweenEvictionRunsMillis=2000
# 控制一个连接在资源池中  最大或最小的生存时间  单位也是毫秒
minEvictableIdleTimeMillis=600000
maxEvictableIdleTimeMillis=900000

public static void main(String[] args) throws Exception{
       	druid();
}

public static void druid() throws Exception {
	String sql = "select username,password from user";
	ResultSet result=null;
	DataSource dataSource = null;
	Connection connection = null;
	PreparedStatement preparedStatement = null;
	Properties properties = new Properties();
	InputStream resourceAsStream = MainClass.class.getClassLoader().getResourceAsStream("druid.properties");
	try {
		properties.load(resourceAsStream);
		dataSource = DruidDataSourceFactory.createDataSource(properties);
		connection = dataSource.getConnection();
		preparedStatement = connection.prepareStatement(sql);
		result = preparedStatement.executeQuery();
		while (result.next()) {
			String str1 = result.getString(1);
			String str2 = result.getString(2);
			System.out.println(str1 + " --- " + str2);
		}
	} catch (Exception e) {
		e.printStackTrace();
	} finally {
		if (result!=null){
      		result.close();
		}
		if (preparedStatement != null) {
			preparedStatement.close();
		}
		if (connection != null) {
			connection.close();
		}
		if (resourceAsStream != null) {
			resourceAsStream.close();
		}
	}
}