如何编写服务类来返回任何实现接口的实现类对象

public interface MyInterface {
    void doSomething();
}

public class MyImplementation1 implements MyInterface {
    @Override
    public void doSomething() {
        System.out.println("Implementation 1: Do something");
    }
}

public class MyImplementation2 implements MyInterface {
    @Override
    public void doSomething() {
        System.out.println("Implementation 2: Do something");
    }
}

public class MyService {
    public MyInterface getImplementation(String className) throws ClassNotFoundException, IllegalAccessException, InstantiationException {
        Class<?> clazz = Class.forName(className);
        Object obj = clazz.newInstance();
        return (MyInterface) obj;
    }
}

public class Main {
    public static void main(String[] args) throws InstantiationException, IllegalAccessException, ClassNotFoundException {
        MyService service = new MyService();
        MyInterface implementation1 = service.getImplementation("MyImplementation1");
        MyInterface implementation2 = service.getImplementation("MyImplementation2");
        implementation1.doSomething();
        implementation2.doSomething();
    }
}