1) What is difference between JDK,JRE and JVM?


Ans).

Understanding the difference between JDK, JRE and JVM is important in Java. We are having brief description of JVM here.

If you want to get the detailed knowledge of Java Virtual  Machine. Firstly, let's see the basic differences between the JDK, JRE and JVM.


JVM
Java Virtual Machine is an abstract machine. It is a specification that provides runtime environment in which java bytecode can be executed.
JVMs are available for many hardware and software platforms. JVM, JRE and JDK are platform dependent because configuration of each OS differs. But, Java is platform independent.
The JVM performs following main tasks:
Loads code
Verifies code
Executes code
Provides runtime environment


JRE

JRE is an acronym for Java Runtime Environment.It is used to provide runtime environment.It is the implementation of JVM.It physically exists.It contains set of libraries + other files that JVM uses at runtime.
Implementation of JVMs are also actively released by other companies besides Sun Micro Systems.

JDK

JDK is an acronym for Java Development Kit.It physically exists.It contains JRE + development tools.

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