How to Install Java on Windows, MacOS, Linux

Introduction

Installing Java is a crucial step for developers who need to run applications written in Java, use development tools like Apache Maven, Apache Ant, and others, or develop Android apps using the Android SDK. This article provides a comprehensive guide on how to install Java on various operating systems.

Understanding Java Editions

Java comes in different editions, each serving different purposes. The two primary editions you might consider installing are:

Java Standard Edition (SE): Used for developing and running Java applications on desktops, servers, and similar devices.
Java Development Kit (JDK): Includes tools for developing Java applications, most notably the Java compiler.

Downloading Java

Before installing Java, you need to download the appropriate version for your system from the official Oracle website or other OpenJDK providers.

Steps to Download Java:

Visit the official Oracle website: Oracle Java or an OpenJDK version like AdoptOpenJDK.
Choose the Java version suitable for your development needs and operating system.
Download the installer package (e.g., .exe for Windows, .dmg for macOS, .tar.gz for Linux).

Installing Java on Windows

Windows users can install Java by following these steps:

Steps for Installation:

Run the Installer: Double-click the downloaded installer file and follow the instructions.
Set Environment Variables:
- Right-click on 'This PC' and select 'Properties'.
- Click on 'Advanced system settings' and then 'Environment Variables'.
- Under 'System Variables', click 'New' and add JAVA_HOME pointing to the Java installation directory (e.g., C:\Program Files\Java\jdk-11.0.1).
- Edit the 'Path' variable to include %JAVA_HOME%\bin.

Installing Java on macOS

Mac users can use the downloaded installer or manage installations via Homebrew, a package manager for macOS.

Installation via Downloaded Installer:

Open the Installer: Double-click the downloaded .dmg file and follow the on-screen instructions.

Installation via Homebrew:

Install Homebrew: If not already installed, open Terminal and run /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
Install Java: Type brew install java.

Installing Java on Linux

For Linux users, Java can be installed from the package manager or by using the tarball downloaded from Oracle.

Installation via Package Manager (e.g., Ubuntu):

Open Terminal.
Update Package List: Run sudo apt update.
Install Java: Type sudo apt install default-jdk.

Installation via Tarball:

Extract Tarball: Run tar zxvf jdk-8uversion-linux-x64.tar.gz.
Move to Installation Directory: Move the extracted folder to /usr/lib/jvm.
Set Environment Variables: Similar to Windows, update the JAVA_HOME and Path variables.

Verifying the Installation

After installation, you can verify that Java is installed correctly by running the following command in your command line interface:

bash
java -version

This command should return the installed Java version.

Conclusion

Installing Java properly allows you to develop and run Java applications effectively. Whether you're setting up a development environment on Windows, macOS, or Linux, following these detailed steps will ensure a successful installation of Java, preparing you for Java development activities.