garbage collection - Life cycle of local Java objects created during a method call

Question

In a method call, if I create an object during that call. When are those objects garbage collected?

Are they placed on the heap and then garbage collected along with other objects on the heap. Or are they garbage collected earlier because they are not needed. The execution of that method has completed.

Answer 1

Objects created within method scope are eligible for garbage collection when the method is closed - unless that reference is passed back as the return value. In that case, the caller may or may not hang onto that reference and prevent it from being gc'd.

Since the garbage collector runs on its own thread according to its own lights, you don't necessarily know when an object is cleaned up, or whether or not objects allocated elsewhere are eligible as well.