Tag: JDK

Java – introduction

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Java is a programming language originally developed by James Gosling Gosling at Sun Microsystems. It was acquired by the Oracle Corporation later.

Top features :

  • object-oriented, follow OOPS concepts like abstraction, encapsulation, inheritance, object-oriented, and polymorphism
  • Multithreading support
  • vast library of predefined objects and operations
  • Just-In_Time Compiler (JIT) to convert bytecode into executables
  • platform-independent thanks to JVM ( Java Virtual Machine ) . Oh, and by the way, JVM is platform dependent.

JRE (Java Runtime Environment )

JRE consists of the Java Virtual Machine (JVM), Java platform core classes, and supporting Java platform libraries.

Java Platform released by Oracle :
Standard Edition
Enterprise Edition
Micro Edition

JDK ( Java Development Development kit )

It is the set of tools to compile, document and package Java programs.

It includes:

  •  appletviewer : to run java applets(without actually using a java-compatible browser).
  • java : java interpreter for reading and interpreting bytecode files.
  • javac : java compiler which translates java source code to bytecode files that the interpreter can understand.
  • javadoc : Creates HTML format documentation from java source code files.
  • javah : Produces header files for use with native methods
  • javap : Java disassembler, enables us to convert bytecode files into a program description.
  • jdb : Java debugger, to find errors

JVM ( Java Virtual Machine )

A program that interprets the intermediate Java byte code and generates the desired output from Machine language code. Hence it provides runtime to execute the code making Java program platform-independent.

JavaFX 

JavaFX platform enables application developers to easily create and deploy Rich Internet Applications (RIA) that behave consistently across multiple platforms.

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Building Standalone JAVA Programs

  1. setting up environment: Give the path for JDK and JRE so that system can find javac and java command .
  2. Else write and store the file in c:\jdk\bin
  3. Make a simple java file with the main method in text editor and save it with .java extension. This makes it a java file . Assume the class-name is altanai.java
  4. Invoke the compiler from the terminal  with the command : javac altanai.java . This creates the altanai.class file .
  5. Run the java interpreter from the terminal with the command:  java altanai

Building Standalone Dynamic JAVA Web Applications

-tbd-