What is difference between JDK, JRE and JVM?

Question

What is the difference between JDK, JRE and JVM in Java?

Sundaram Subramanian · Answer

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.

Rajkiran Swain · Answer

JVM The Java Virtual machine (JVM) is the virtual machine that runs the Java bytecodes. The JVM doesn't understand Java source code, that's why you compile your *.java files to obtain *.class files that contain the bytecodes understood by the JVM. It's also the entity that allows Java to be a "portable language" ( write once, run anywhere ). Indeed, there are specific implementations of the JVM for different systems (Windows, Linux, MacOS, see the Wikipedia list), the aim is that with the same bytecodes they all give the same results. JDK and JRE To explain the difference between JDK and JRE, the best is to read the Oracle documentation and consult the diagram: Java Runtime Environment (JRE) The Java Runtime Environment (JRE) provides the libraries, the Java Virtual Machine, and other components to run applets and applications written in the Java programming language. In addition, two key deployment technologies are part of the JRE: Java Plug-in, which enables applets to run in popular browsers; and Java Web Start, which deploys standalone applications over a network. It is also the foundation for the technologies in the Java 2 Platform, Enterprise Edition (J2EE) for enterprise software development and deployment. The JRE does not contain tools and utilities such as compilers or debuggers for developing applets and applications.

Naveen Arumugam · Answer

Its easy to understand...Thank You