JAVA JVM

JVM is called as Java Virtual Machine or an abstract machine. It is called a virtual machine because it doesn't physically exist. It is a specification that provides a runtime environment in which Java bytecode can be executed. 

A Java virtual machine is a virtual machine that enables a computer to run Java programs as well as programs written in other languages that are also compiled to Java bytecode.

Java applications are called Write Once Run Anywhere. This means a programmer can develop Java code on one system and can expect it to run on any other Java-enabled system without any adjustment. This is all possible because of JVM.

JVM architecture

JVM architecture in Java contains classloader, memory area, execution engine etc as belows.

1. ClassLoader
2. Method Area
3. Heap
4. JVM language Stacks
5. PC Registers
6. Native Method Stacks
7. Execution Engine
8. Native Method interface
9. Native Method Libraries

Software Code Compilation & Execution process

We need the following to write and execute a software program.

1. Editor
2. Compiler
3. Linker
4. Loader
5. Execution