Q 10) Heap And Stack ?

Java Heap Memory:

•    Heap memory is used by java runtime to allocate memory to Objects and JRE classes.

•     Whenever we create any object, it’s always created in  the Heap space.

•      Garbage Collection runs on the heap memory to free  the memory used by objects that doesn’t have any  reference.

•       Any object created in the heap space has global access  and can be referenced from anywhere of the  application.

Java Stack Memory:

•     Java Stack memory is used for execution of a thread. They contain method specific values that are short-lived and references to other objects in the heap that are getting referred from the method.

•     Stack memory is always referenced in LIFO (Last-In-First-Out) order.

•     Whenever a method is invoked, a new block is created in the stack memory for the method to hold local primitive values and reference to other objects in the method.

•     As soon as method ends, the block becomes unused and become available for next method.

•     Stack memory size is very less compared to Heap memory.