JVM Architecture

 

 JVM Architecture
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Class loader sub system does the following tasks.
1)It loads .class files into memory(i.e.,RAM).
2)It verifies byte code instructions.
3)It allots neccessary memory needed by the program.
   The memory alloted by class loader sub system is divided into 5 parts called Run-time areas. They are
1)Method area:-
     The class code and methods code is stored on method area.
2)Heap:-
     Objects will be created by the JVM on heap memory.
3)Java stacks:-
     These are the places where Java methods are executed
4)PC (program counter) registers:-
They are provide memory address of the next instruction to be executed by the Micro-processor.
5)Native method stacks:-
    These are the places where native methods(c,c++ programs) are executed.

Note:- Native method interface is a program that copies native method libraries(c,c++ header files) into JVM.
  since,Jvm can run c,c++ programs also.

Execute engine:-
   It contains interpreter and JIT(Just in Time) compiler which converts byte code into mechine code.So that the processor executes it and displays the result.

Hotspot:-
           It is a block of code executed by JIT compiler.
          So Jvm is known as Hotspot JVM.