finalize method in java is a special method much like the main method in java. finalize() is called before Garbage collector reclaim the Object, its last chance for any object to perform cleanup activity i.e. releasing any system resources held, closing connection if open etc. The main issue with finalize method in Java is it's not guaranteed by JLS that it will be called by Garbage collector or exactly when it will be called, for example, an object may wait indefinitely after becoming eligible for garbage collection and before its finalize() method gets called. similarly even after finalize gets called it's not guaranteed it will be immediately collected. Because of above reason it makes no sense to finalize method for releasing critical resources or perform any time critical activity inside finalize. It may work in development in one JVM but may not work in other JVM.
