Question

I have several classes that all have DoSomething() method within them. And a separate function that expects a Class as a parameter:

public void DoStuff(Class c) {
     c.DoSomething();
} 

But this code throws error: DoSomething() is undefined for the type Class. I also tried instantiating the Class like this:

public void DoStuff(Class c) {

Object o;

try {
   o = c.newInstance();
} catch (InstantiationException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
} catch (IllegalAccessException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
}
} 

And then calling the DoSomething() method, but i get the same error.

What’s the correct way to pass a class as a parameter?

Answer 1

Create an interface that declares your method doSomething like this:

   public interface Something {
      void doSomething();   
   }

and then have your class implement this interface like:

public class SomeClass implements Something {
    public void doSomething() {
        // do what?
    }
}

You can then do

public void DoStuff(Something pInstance) {
   pInstance.doSomething();
}