anonymous inner class

[Anonymous]

Hello All:
This question is from Javacaps Mock Exam.
Which of the following statements are true ?
a. An anonymous inner class cannot have any constructors.
b. An anonymous inner class can be created only inside a method.
c. An anonymous inner class can only access static fields of the enclosing class.
d. An anonymous inner class can implement an interface.
I think
a)true.
b)true. NOT SURE
c)false. It can access static as well as not-static fields of the enclosing class.
d)true. In the below code anonymous inner class is implementing ActionListener interface
button1.addActionListener(
new ActionListener() {
public void actionPerformed(ActionEvent e) {
.....
}
}
);
Please let me know if I'm wrong.
Thanks

[softie]

Hi
I feel that the answers you have entered are perfectly right.
Cheers
Venu

[Anonymous]

Yes, I think d is true too. But I think b is false. pls see:
Thread t = new Thread(new Runnable() {
public void run() {
//....
}
});

[Anonymous]

yiqinye,
Don't you think the code you mentioned must reside in some method/constructor ?
I don't know may be I'm moving in wrong direction.

[Anonymous]

This is from http://developer.java.sun.com/developer/Books/certification/page5.html
Some classes that you define inside a method do not need a name. A class defined in this way without a name is called an anonymous class. Clearly you cannot use new in the usual way to create an instance of a class if you do not know its name. In fact, anonymous classes are defined in the place they are constructed:
Ajit, Maha Anna, Paul any comments on this issue ?
Thanks

[Anonymous]

I think the anonymous class implementing Runnable interface i defined is not inside a method but belongs to an object of the enclosing class in which the reference variable Thread t was declared. do u agree?

[Anonymous]

Sounds perfect....
public class Class1 {
Thread t = new Thread(
new Runnable() {
public void run() {
System.out.println("In run method");
}
}
);
public static void main(String args[]) {
Class1 c = new Class1();
}
Class1() { t.start();}
}

[Ajith Kallambella]

Only (a) and (d) are the right answers.
Dilip, I can help you, but what is the issue here you are confused with?
Ajith

[Anonymous]

Ajith,
I was thinking that anonymous inner class can be created "only inside a method".
But yiqingye made me clear that it can be created outside method also.
Thanks for quick response.

[Jim Goodwin]

With regard to point (b):
I believe the sense of "inside" intended by the question refers to lexical scope, so it asks whether you can write
"... new Button() { blah blah };"
anywhere that is not within the outer {} of a method declaration.
And Dilip was on the right track before he got convinced to give up. I think the answer to the question is: False. You can write the above in a constructor as well (which is not technically a method) and in a static initializer too (which is not a method at all).
yiqingye got off on another idea entirely, I think because he understood "inside" in terms of the structural organization of the runtime data. But I don't understand what he meant well enough to say whether I think it's right.
jim goodwin