java - 如何基于接口实现创建新对象(How to create a new object based on interface implementation)

Question

Firstly, I believe my question is badly worded but don't really understand how to phrase it.

(首先，我认为我的问题措辞不佳，但并不真正理解该措辞。)

I have a starting interface that is being implemented by a number of classes.

(我有一个由多个类实现的启动接口。)

What I want to do is to see if there is a way to create a new object such that I am being passed the generic interface, then based on the method .getClass().getSimpleName(), create a new object based on that string.

(我想做的是查看是否有一种方法可以创建一个新对象，从而使我被传递给通用接口，然后基于.getClass（）。getSimpleName（）方法，基于该字符串创建一个新对象。 。)

Is the only way to create a switch case statement?

(是创建switch case语句的唯一方法吗？)

As the number of implementing classes are too many (about 100 or so).

(由于实现类的数量太多（大约100个左右）。)

Reference code:

(参考代码：)

public interface MyInterface {
  public void someMethod();
}

then I would have my implementing classes:

(然后我将有我的实现类：)

public class MyClass1 implements MyInterface {
  public void someMethod() { //statements }
}

public class MyClass2 implements MyInterface {
  public void someMethod() { //statements }
}

public class MyClass3 implements MyInterface {
  public void someMethod() { //statements }
}

What I want to have in the end is another class which is passed an argument of type MyInterface, get the simple name from that and create a new instance of MyClassX based on that simple name.

(最后，我要提供的另一个类是传递给MyInterface类型的参数的类，从中获取简单名称，然后基于该简单名称创建MyClassX的新实例。)

public class AnotherClass {
  public void someMethod(MyInterface interface) {
    if (interface == null) {
      System.err.println("Invalid reference!");
      System.exit(-1);
    } else {
      String interfaceName = interface.getClass().getSimpleName();
      /**
       * This is where my problem is!
       */
      MyInterface newInterface = new <interfaceName> // where interfaceName would be MyClass1 or 2 or 3...
    }
  }
}

Any help is highly appreciated!

(任何帮助深表感谢！)

  ask by Mariosyian translate from so

Answer 1

You can use reflection for this:

(您可以为此使用反射：)

public void someMethod(MyInterface myInterface) {
Class<MyInterface> cl = myInterface.getClass();
MyInteface realImplementationObject = cl.newInstance(); // handle exceptions in try/catch block
}