Method-Local Inner Class and Local Variable

[Mateus Brum]

The local variables of the method live on the stack, and exist only for
the lifetime of the method. You already know that the scope of a local variable is
limited to the method the variable is declared in. When the method ends, the stack
frame is blown away and the variable is history. But even after the method
completes, the inner class object created within it might still be alive on the heap if,
for example, a reference to it was passed into some other code and then stored in an
instance variable. Because the local variables aren't guaranteed to be alive as long
as the method-local inner class object, the inner class object can't use them. Unless
the local variables are marked final!

Why M-LIC can access a final marked variable and not a simple variable?
If the problem is the life cycle of the local variable - the variable die with the stack of method -, why a final don�t die ?

[Henry Wong]

Originally posted by Mateus Brum:

Why M-LIC can access a final marked variable and not a simple variable?
If the problem is the life cycle of the local variable - the variable die with the stack of method -, why a final don�t die ?

M-LIC? Please don't make up acronyms. It makes your question harder to understand. And I am assuming that you want people to actually understand your question, right?


As for your question, it is just how it is specified. Java will make a copy of the local variable for the inner class, but the inner class doesn't know that it is a copy. This way, it is no longer tied to the scope of the method.

But, for it to work, the spec requires that the original value doesn't change -- meaning that it is final.

Henry

[marc weber]

Originally posted by Henry Wong:
... M-LIC? ...

This is clearly meant to indicate a class M (Motorcycle) driver's license.

But seriously, I would like to see a source cited for this quote.