Block Diagram Of Java Virtual Machine

Class loader sub system in Java Virtual Machine(JVM) will do the following tasks.

1.It loads the dot class files into memory.

2.Then it verifies byte code instructions.

3.Finally it will allot memory needed for the program.

Note:Class loader is a piece of software that is part of JVM and it is used to read the information available in the "dot class" file and put this information in the method area.

Note: We get dot class files(these files contain 'byte code') when we compile our source code.


The memory is divided into five parts called run-time data areas.

Method Area: Method area is used for storing the information about the java classes.

Stack Space: When the JVM runs a method it stores the parameters and the local variables of the method in the memory area called as stack space.

Heap Area : Objects are created on "Heap Area".

Java Stacks: Java stacks are the places where Java methods are executed. Each method is executed on a separate frame in Java Stacks.

Program Counter Register's: These registers show memory address of the next instruction to be executed by the micro processor.

Native Method Stacks:Native method stacks are executed on native method stacks.

Execution Engine: This contains interpreter and Just in Time Compiler(JIT) which converts the byte code into the machine code so that the micro processor will execute that machine code and display the results.