Introduction To Java

In This Blog, We Will Learn About the Basics of the Java language such as JDK, JVM, JRE, Compile Time And Run Time etc. This is from 7th video lecture of DSA Playlist By Kunal Kushwaha

Java Development Kit

Java Runtime Environment

Java Virtual Machine

Just In Time Compiler

Computer Machines understand the language of Binary Language (0's and 1's). But it is difficult for human beings to understand this language and writing code in it is a very tedious job.

So Programmers have found a solution to it such that anybody can code in a human-understandable language, which is known as a Programming language.

Examples of Programming languages are Java, C++, C, JavaScript etc.

Here we are going to do the basics of Java.

Image credits: Kunal Kushwaha

Here In The above picture, we can see the mechanism behind the compilation and interpretation of a java file.

The code in human-readable format is written in and saved with .java extension. Then the entire file is compiled with .javac compiler and it is converted into bytecode with the .class extension.

This bytecode can be run on any operating system with the help of a Java virtual machine . Therefore Java is Platform Independent. We obtained machine-level code (0's and 1's).

Now, We will discuss what is Java Development Kit (JDK), Java Runtime Environment (JRE), Java Virtual Machine (JVM), and Just In Time (JIT).

Image credits: Kunal Kushwaha

Java Development Kit (JDK)

Java Development Kit can be installed through Oracle, download it using your Operating System

Java Development Kit Download

JDK provides an environment to deploy and execution of Java files.

Java Runtime Environment (JRE)

Java Runtime Environment provides facilities to run the java program only

JRE = JVM + docs generator (.javadoc) + interpreter + development tools + archiver

Java Virtual Machine (JVM)

Java Virtual Machine converts byte code into machine code.

This feature of Java makes it platform-independent.

JVM = JIT + User Interface Toolkit + Deployment Technologies + Integration Libraries + Base Libraries

Just in Time (JIT)

JIT = Java Interpreter + Garbage Collector

Reference Links

Introduction To Java