Java Heap Space

When a java program starts JVM gets some memory from operating operating system. JVM uses this memory for all its need and part of this memory is call java heap memory. Heap in Java generally located at bottom of address space and move upwards. whenever we create object using new operator or by any another means object is allocated memory from Heap and When object dies or garbage collected, memory goes back to Heap space in Java.

An Object becomes eligible for Garbage collection or GC if its not reachable from any live threads or any static references in other words you can say that an object becomes eligible for garbage collection if its all references are null.

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