How does Java Garbage Collection work with Circular References?

Question

From my understanding, garbage collection in Java cleans up some objects if nothing else is \'pointing\' to that object.

My question is, what happens if we have some

Answer 1

Java's GC considers objects "garbage" if they aren't reachable through a chain starting at a garbage collection root, so these objects will be collected. Even though objects may point to each other to form a cycle, they're still garbage if they're cut off from the root.

See the section on unreachable objects in Appendix A: The Truth About Garbage Collection in Java Platform Performance: Strategies and Tactics for the gory details.