Finalizer

Every class has a special method, called a finalizer, which is called before an object is reclaimed by the Java VM garbage collector. The JVM calls the finalizer for you as appropriate; you never call a finalizer directly. Think of the finalizer as a friendly warning from the virtual machine. Your finalizer should perform two tasks: performing whatever cleanup is appropriate to the object, and
calling the superclass finalizer. Finalizers are not guaranteed to be called just because an object becomes eligible for garbage collection, or before a program shuts down,
so you should not rely on them.