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Accessing Effectively Final Variables From Anonymous Inner Classes in Java 8
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Before Java 8, you could only use final variables from a surrounding class in an anonymous inner class. In Java 8, within anonymous class (or lambda expressions) you can use effectively final variables: not declared as final but only assigned once.
Important points about accessing variables from within an anonymous inner class (or lambda expression)
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If you don't assign any value and try to access it from within a lambda expression, you will get the older error that the variable might not have been initialized.
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You cannot reassign a local variable even after being used in the lambda expression. You will get error within the lambda expression where you actually use it.
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There is not restriction on the use of instance or static variables within a lambda expression or an anonynous inner class.
TODO
Add examples, before and after telling which line code will fail. For all cases.
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