Linux Java Guide - ryzendew/Linux-Tips-and-Tricks GitHub Wiki

Linux Java Guide

Complete beginner-friendly guide to Java on Linux, covering Arch Linux, CachyOS, and other distributions including installation, JDK setup, and Java development.

Table of Contents

  1. Java Installation
  2. JDK Setup
  3. Java Development
  4. IDE Setup
  5. Troubleshooting

Java Installation

Install Java

Arch/CachyOS:

# Install OpenJDK
sudo pacman -S jdk-openjdk

# Or Oracle JDK
yay -S jdk

# Check version
java --version

Debian/Ubuntu:

sudo apt install default-jdk

Fedora:

sudo dnf install java-latest-openjdk-devel

Verify Installation

Check Java:

# Check version
java --version
javac --version

# Check JAVA_HOME
echo $JAVA_HOME

JDK Setup

Set JAVA_HOME

Configure environment:

# Set JAVA_HOME
export JAVA_HOME=/usr/lib/jvm/default

# Make permanent
echo 'export JAVA_HOME=/usr/lib/jvm/default' >> ~/.bashrc

Multiple JDK Versions

Switch versions:

# List installed JDKs
archlinux-java status

# Set default
sudo archlinux-java set java-11-openjdk

Java Development

Hello World

Basic program:

public class Hello {
    public static void main(String[] args) {
        System.out.println("Hello, World!");
    }
}

Compile and Run

Build:

# Compile
javac Hello.java

# Run
java Hello

IDE Setup

IntelliJ IDEA

Install IntelliJ:

# Arch/CachyOS
yay -S intellij-idea-community-edition

# Launch
idea

Eclipse

Install Eclipse:

# Arch/CachyOS
sudo pacman -S eclipse-java

Troubleshooting

Java Not Found

Check installation:

# Check Java
which java
which javac

# Install if missing
sudo pacman -S jdk-openjdk

Version Issues

Check version:

# List versions
archlinux-java status

# Set version
sudo archlinux-java set java-17-openjdk

Summary

This guide covered Java installation, JDK setup, and development for Arch Linux, CachyOS, and other distributions.

Next Steps

This guide covers Arch Linux, CachyOS, and other Linux distributions. For distribution-specific details, refer to your distribution's documentation.