can interface declare.....???

[Aftab Ahmed]

Hi Frndz,
can interface declare in local inner class?? coz i try to do this give me compile time error why??

thanx
Aftab Abbasi

[Ajith Kallambella]

Why not?? Try this code

interface LocalInsideIFace
{
    static class LocalInnerClass1
    {
        void someMethod() { }
    }
    /*non static */ class LocalInnerClass2
    {
        void someMethod2() { }
    }
}

Since methods inside an interface cannot have a body, you will not be able to declare innerclasses within methods inside the interface. Top level classes are permitted and legal.
Ajith

[Aftab Ahmed]

thanx Ajith u help me, and onething more can local inner class declare interface if yes plz give any example
thanx
Aftab Abbasi

[Ajith Kallambella]

Aftab,
The best tool to learn Java is the Java compiler itself( javac.exe ). Whenever you don't understand a concept, write code and play with it. Nothing helps you more than hands-on learning experience.
Having said that, why don't you try to compile the following program and see what happens.

class Outer
{
    interface IFaceInClassScope
    {
        public void FooBar3() ;    
    }
    
    
    class Inner
    {
        interface IFaceInInnerClassScope 
        {
            public void FooBar() ;
        }
    
    
        public void CoolMethod()
        {
            class InnerClassWithinAMethod
            {
                interface IFaceInLocalInnerClassScope
                {
                    public void FooBar2() ;
                }
            }
        }
    }
}

Good luck,
Ajith

[Aftab Ahmed]

Hi Aijth,
thanx help me and give example code also. but your last code dosn't complie and give following error which given belown.
Outer.java:5: Member interfaces can only occur in interfaces
and op-level classes.
interface IFaceInInnerClassScope
^
Outer.java:10: Member interfaces can only occur in interfaces
and top-level classes.
IFaceInLocalInnerClassScope
^
2 errors
hope u tell me about this
thanx
Aftab

[vadiraj vd]

Hi Aftab,
You posted an interresting topic.
Now to your question.
As you may be knowing there are four types of nested classes/interfaces possible in Java.
*) Top-level nested class/interface.
*) Non-static class.
*) Local class.
*) Anonymous class.
The top-level classes are the static classes defined inside another class.
All the nested interfaces are by default static . meaning there's no thing like non-static interface or local interface defined inside a method.
So the compiler says just that.
Refer Khalid for more information.


------------------
Regards
---------
vadiraj

*****************
There's a lot of I in J.
*****************

[Aftab Ahmed]

thanx vadiraj vd for help
Aftab Abbasi