How does the garbage collector work in Java?

Garbage collection is the process of automatically managing memory in java. It is helpful to finds the unused objects that are no longer used by the program and deletes or remove them to free up the memory. The internal structure of the garbage collection mechanism uses several GC algorithms. It works with the most popular algorithm such as Mark and Sweep. Garbage collection is controlled by a thread known as Garbage Collector.

In Java, System.gc() and Runtime.gc() are two methods that sends requests to the JVM for garbage collection. It totally depends on the JVM. If the Heap Memory is full, the JVM will not allow creating a new object and shows an error java.lang.OutOfMemoryError. When the garbage collector removes the object from the memory, first, the garbage collector thread calls the finalize() method of that object and then remove it.