JVM Architecture

I. Class Loader Sub system :


    1. Loads the .class files into memory.
    2. Verifies the byte code.
    3. Allocates memory to execute the program which is divided into    
       5 areas called runtime data areas viz.


                     a). Method Area.
                     b). Heap
                     c). Java Stacks
                     d). pc registers
                     e). native method stacks


II. Native method interface connects native libraries to JVM.


III. Execution Engine consist of interpreter and JIT(Just In Time) compiler.


    a. Single Instruction is executed by interpreter
    b. Block of Instruction (called HotSpot) is executed by JIT compiler