使用枚举数据类型实现单例模式

如：

public enum  MyObject {
connectionFactory;
private Connection connection;
private MyObject(){
try {
            System.out.println("调用了MyObject的构造");
            String url="jdbc:oracle:thin:@118.192.22.167:1521/lbdtest01";
            String username="lbdtest01";
            String pwd="lbd%^test01";
            String driverName="oracle.jdbc.driver.OracleDriver";
            Class.forName(driverName);
connection= DriverManager.getConnection(url,username,pwd);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
public Connection getConnection(){
return connection;
    }
}
class MyThread extends  Thread{
@Override
public void run() {
for (int i = 0; i < 5; i++) {
            System.out.println(MyObject.connectionFactory.getConnection().hashCode());
        }
    }
}
class MyRun{
public static void main(String[] args) {
        MyThread t1=new MyThread();
        MyThread t2=new MyThread();
        MyThread t3=new MyThread();
        t1.start();
        t2.start();
        t3.start();
    }
}