anonymous-inner-class

I think I understand the basics of Anonymous classes but I'd like to clarify something. when I have a syntax such as this class A { class AnonymousClass1 Implements ActionListener{} } class A { public A() { JButton btn = new JButton(); btn.addActionListener( new ActionListener(){} ); } } If the anonymous class is actually an inner class of class A, as in the first example: in theory, is the semantics right? What happens exactly? I think when the java file is compiled, a .class file is created for the anonymous class so it can be referenced (but I couldn't find it). When an object of A is

in Java android application how can i access variables of outer class from the inner anonymous class ? Example: ProgressDialog dialog = new ProgressDialog(this); ..... send.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { //here i'd like to do something with **dialog** variable ....... } }); If the dialog variable is a field of the outer class, you can use this prefixed with the outer class name ( a qualified this ): send.setOnClickListener(new View.OnClickListener() { public void onClick(View v) { ProgressDialog dlg = OuterClass.this.dialog; ....... } });

What is the difference between these two ways of instantiating new objects of a class as follows: Test t1=new Test(); Test t2=new Test(){ }; When I tried the following code, I could see that both objects could access the method foo() , but t2 cannot access the variable x ( variable x cannot be resolved): public class Test { int x=0; public void foo(){ } public static void main (String args[]) { Test t1=new Test(); Test t2=new Test(){ }; t1.x=10; t2.x=20; t1.foo(); t2.foo(); System.out.println(t1.x+" "t2.x); } } Test t2=new Test(); will create the object of Test class. But Test t2=new Test(){ }

I'm in the process of writing a C# Wicket implementation in order to deepen my understanding of C# and Wicket. One of the issues we're running into is that Wicket makes heavy use of anonymous inner classes, and C# has no anonymous inner classes. So, for example, in Wicket, you define a Link like this: Link link = new Link("id") { @Override void onClick() { setResponsePage(...); } }; Since Link is an abstract class, it forces the implementor to implement an onClick method. However, in C#, since there are no anonymous inner classes, there is no way to do this. As an alternative, you could use

I have a enum type class: public enum Operation { PLUS() { @Override double apply(double x, double y) { // ERROR: Cannot make a static reference // to the non-static method printMe()... printMe(x); return x + y; } }; private void printMe(double val) { System.out.println("val = " + val); } abstract double apply(double x, double y); } As you see above, I have defined one enum type which has value PLUS . It contains a constant-specific body. In its body, I tried to call printMe(val); , but I got the compilation error: Cannot make a static reference to the non-static method printMe(). Why do I get