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Java Environment Setup

Installing the JDK is just the first step. A complete Java development environment includes a configured IDE, a build tool, version management, and the right JVM settings for your workflow. Here's how to set up a professional Java environment from scratch.

The Complete Java Toolchain

A professional Java environment has five components working together: - JDK — The compiler and runtime. The foundation everything else needs. - JAVA_HOME — Environment variable pointing to the JDK. Required by build tools. - IDE — IntelliJ IDEA or VS Code. Where you write and debug code. - Build Tool — Maven or Gradle. Manages dependencies, compilation, and packaging. - Version Manager (optional but recommended) — SDKMAN for switching between Java versions. You can write Java with just the JDK and a text editor. But adding the other pieces is what takes you from running experiments to building real software.

Step 1 — Install the JDK

Install Java 21 (current LTS). Eclipse Temurin is the recommended open-source distribution — it's what most enterprises use.

Shell

# macOS (Homebrew):
brew install --cask temurin@21

# Ubuntu/Debian:
sudo apt update && sudo apt install openjdk-21-jdk

# Windows — download installer from: adoptium.net

# Verify:
java -version && javac -version

Step 2 — Configure JAVA_HOME

Build tools read JAVA_HOME to find the JDK. Set it in your shell profile so it persists across sessions.

Shell

# macOS (add to ~/.zshrc):
export JAVA_HOME=$(/usr/libexec/java_home -v 21)
export PATH=$JAVA_HOME/bin:$PATH

# Linux (add to ~/.bashrc):
export JAVA_HOME=/usr/lib/jvm/java-21-openjdk-amd64
export PATH=$JAVA_HOME/bin:$PATH

# Reload:
source ~/.zshrc     # or source ~/.bashrc

# Verify:
echo $JAVA_HOME

Step 3 — Choose and Configure an IDE

IntelliJ IDEA is the industry standard for Java. The free Community Edition covers everything you need — commercial frameworks like Spring are supported through plugins. After installing IntelliJ: 1. Open Preferences → Build, Execution, Deployment → Build Tools → Maven/Gradle 2. Set the JDK: File → Project Structure → SDK → add your JDK path 3. Install plugins: Lombok (if using Lombok), SonarLint (code quality), GitToolBox VS Code is a good lightweight alternative. Install the "Extension Pack for Java" by Microsoft — it adds IntelliSense, debugging, Maven/Gradle support, and test running.

Step 4 — Install a Build Tool

Maven and Gradle are the two dominant Java build tools. Both manage dependencies, compile your code, run tests, and package your application. Gradle is faster; Maven is more established in enterprise environments.

Shell

# Install Maven (macOS):
brew install maven
mvn -version

# Install Gradle (macOS):
brew install gradle
gradle -version

# Install Maven (Ubuntu):
sudo apt install maven

# Create a new Maven project from the command line:
mvn archetype:generate   -DgroupId=com.example   -DartifactId=my-app   -DarchetypeArtifactId=maven-archetype-quickstart   -DinteractiveMode=false

# Create a new Gradle project:
mkdir my-app && cd my-app
gradle init --type java-application

Step 5 — SDKMAN for Version Management

If you work on multiple Java projects, they may require different Java versions. SDKMAN makes switching between versions a single command — and it manages Maven, Gradle, and other JVM tools too.

Shell

# Install SDKMAN (macOS/Linux):
curl -s "https://get.sdkman.io" | bash
source "$HOME/.sdkman/bin/sdkman-init.sh"

# Install Java versions:
sdk install java 21-tem       # Eclipse Temurin 21
sdk install java 17-tem       # Eclipse Temurin 17
sdk install java 21-graalce   # GraalVM Community 21

# Switch versions:
sdk use java 17-tem           # switch for current session
sdk default java 21-tem       # set permanent default

# Install build tools via SDKMAN:
sdk install maven
sdk install gradle

# List all available Java versions:
sdk list java

Verifying the Full Setup

Run through this checklist to confirm everything is wired correctly:

Shell

# 1. JDK installed and on PATH:
java -version
javac -version

# 2. JAVA_HOME set correctly:
echo $JAVA_HOME
ls $JAVA_HOME/bin/javac   # should exist

# 3. Build tool working:
mvn -version      # or: gradle -version

# 4. Create and run a test project end-to-end:
mkdir TestProject && cd TestProject
cat > Main.java << 'EOF'
public class Main {
    public static void main(String[] args) {
        System.out.println("Environment works!");
    }
}
EOF
javac Main.java && java Main
# Output: Environment works!

Java Environment Setup

The Complete Java Toolchain

Step 1 — Install the JDK

Step 2 — Configure JAVA_HOME

Step 3 — Choose and Configure an IDE

Step 4 — Install a Build Tool

Step 5 — SDKMAN for Version Management

Verifying the Full Setup

Related Topics in Introduction