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static - problem creating object of inner class in java


Here is the code.

public class Test {
        class InnerClass{

               }

   public static void main(String[] args){
            InnerClass ic = new InnerClass();
        }
    }

It says the error message

non-static variable this cannot be referenced from a static context
after creation of object ic.

Can anyone give me the reason?

Thanks

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1 Answer

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by (71.8m points)

InnerClass needs to be static itself, i.e.

public class Test {

   static class InnerClass{    
   }

   public static void main(String[] args){
      InnerClass ic = new InnerClass();
   }
}

If InnerClass is not static, it can only be instantiated in the context of a parent instance of Test. The rather baroque syntax for this is:

public class Test {

   class InnerClass{    
   }

   public static void main(String[] args){
      Test test = new Test();
      InnerClass ic = test.new InnerClass();
   }
}

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