How does Java Garbage Collection work with Circular References?

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.

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