What is the Use of Inner classes

[painless]

Can any one justify the use of inner classes with example(if possible)

[Ramy Mahrous]

To be visible to just parent class.

namespace Example
{
class Parent 
{
void Method()
{
Child c = new Child();//No error
}
class Child
{
}
}
class Painless
{
void Method()
{
Child c = new Child();//error
}
}
}

[JamesCherrill]

Sometimes you need an instance of a class - eg as a Listener for a Swing Event,, or a Runnable for a Thread - and these are most conveniently and compactly created locally as inner classes, often anonymous inner classes.

[BestJewSinceJC]

And inner classes can provide specific functionality for their parent classes. There are relevant examples in the Sun tutorials on inner classes.