Java Garbage Collection Explained: Mechanisms and Best Practices

Java Garbage Collection (GC) is an automatic memory management process that helps reclaim unused memory. Java uses several garbage collectors, such as Serial, Parallel, and G1. Each serves different needs.

The garbage collector works in the background, identifying objects that are no longer referenced and removing them from memory. To make your application GC-friendly, avoid creating too many short-lived objects. Here’s an example to force garbage collection:

public class GarbageCollectionDemo {
    public static void main(String[] args) {
        GarbageCollectionDemo demo = new GarbageCollectionDemo();
        demo = null;
        System.gc();  // Requesting JVM to run Garbage Collection
    }
}
            

In this example, setting the object to null and calling System.gc() suggests that garbage collection should occur. However, it’s just a request, and the JVM decides when to actually run it. To improve performance, it’s important to choose the right garbage collector for your application’s needs.