Data Structures and Algorithms
with Object-Oriented Design Patterns in Java 
The preceding section presents strategies for avoiding garbage collection. However, there are times when garbage collection is actually desirable. Imagine a program that requires a significant amount of memory. Suppose the amount of memory required is very close to the amount of memory available for use by the Java virtual machine. The performance of such a program is going to depend on the ability of the garbage collector to find and reclaim as much unused storage as possible. Otherwise, the garbage collector will run too often. In this case, it pays to help out the garbage collector.
How can we help out the garbage collector? Since the garbage collector collects only unreferenced objects it is necessary to eliminate all references to objects which are no longer needed. This is done by assigning the value null to every variable that refers to an object that is no longer needed. Consequently, helping the garbage collector requires a program to do a bit more work.
Copyright © 1998 by Bruno R. Preiss, P.Eng. All rights reserved.