TP1.1 — Installation of Java JDK 17

Objectives

This practical work will allow you to:

• Install the JDK 17 (Java Development Kit) on your operating system
• Configure environment variables (JAVA_HOME, PATH)
• Verify the installation with the commands java, javac, and which java
• Understand the difference between JDK, JRE, and the different distributions

Estimated duration: 20-30 minutes

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Why Java 17?

Reason	Detail
LTS (Long Term Support)	Long-term support by Oracle and the community (until 2029+)
Spring Boot 3.x	Minimum version required by Spring Boot 3
Modern features	Records, sealed classes, pattern matching, text blocks
Stability	Proven production version since 2021

Which distribution to choose?

• Eclipse Temurin (Adoptium) — Recommended, free, open source
• Oracle JDK — Free for development, commercial license in production
• Amazon Corretto — Free, maintained by Amazon
• Azul Zulu — Free, certified

We recommend Eclipse Temurin for this course.

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Installation on Windows

🪟 Click here for Windows installation (graphical method)

Step 1: Download the JDK 17

1. Go to https://adoptium.net/
2. Select:
   • Operating System: Windows
   • Architecture: x64
   • Package Type: JDK
   • Version: 17 (LTS)
3. Click on "Latest LTS Release" to download the .msi file

Direct link

Temurin JDK 17 Windows x64 (.msi)

Step 2: Install the JDK

1. Double-click the downloaded .msi file
2. Follow the installation wizard
3. IMPORTANT: During installation, check these options:
   • ✅ Add to PATH
   • ✅ Set JAVA_HOME variable
   • ✅ Associate .jar files

┌──────────────────────────────────────┐
│  Eclipse Temurin JDK 17 Setup        │
│                                      │
│  ✅ Add to PATH                      │
│  ✅ Set JAVA_HOME variable           │
│  ✅ Associate .jar                   │
│                                      │
│  Install to: C:\Program Files\       │
│  Eclipse Adoptium\jdk-17.0.x.x\     │
│                                      │
│           [Install]                  │
└──────────────────────────────────────┘

Step 3: Verify the installation

Close all open terminals, then open a new PowerShell or CMD:

java -version

Expected result:

openjdk version "17.0.13" 2024-10-15
OpenJDK Runtime Environment Temurin-17.0.13+11 (build 17.0.13+11)
OpenJDK 64-Bit Server VM Temurin-17.0.13+11 (build 17.0.13+11, mixed mode, sharing)

javac -version

Expected result:

javac 17.0.13

Step 4: Verify JAVA_HOME

$env:JAVA_HOME

Expected result:

C:\Program Files\Eclipse Adoptium\jdk-17.0.13.11-hotspot

where.exe java

Expected result:

C:\Program Files\Eclipse Adoptium\jdk-17.0.13.11-hotspot\bin\java.exe

If JAVA_HOME is not set automatically

1. Start Menu → type "environment variables"
2. Click on "Edit the system environment variables"
3. Click on "Environment Variables..."
4. In System variables, click on New:
   • Name: JAVA_HOME
   • Value: C:\Program Files\Eclipse Adoptium\jdk-17.0.13.11-hotspot
5. Find the Path variable → Edit → New:
   • %JAVA_HOME%\bin
6. OK everywhere → Restart the terminal

🪟 Windows installation with Chocolatey (quick alternative)

If you have Chocolatey installed:

choco install temurin17

Verification:

java -version
javac -version
$env:JAVA_HOME
where.exe java

Chocolatey automatically configures JAVA_HOME and the PATH.

🪟 Windows installation with Scoop (quick alternative)

If you have Scoop installed:

scoop bucket add java
scoop install temurin17-jdk

Verification:

java -version
javac -version
$env:JAVA_HOME
where.exe java

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Installation on macOS

🍎 macOS installation with Homebrew (Recommended)

Step 1: Install Homebrew (if not already done)

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

Step 2: Install the JDK 17

brew install --cask temurin@17

Step 3: Verify the installation

java -version

Expected result:

openjdk version "17.0.13" 2024-10-15
OpenJDK Runtime Environment Temurin-17.0.13+11 (build 17.0.13+11)
OpenJDK 64-Bit Server VM Temurin-17.0.13+11 (build 17.0.13+11, mixed mode)

javac -version

Expected result:

javac 17.0.13

Step 4: Verify the path and JAVA_HOME

which java

Expected result:

/Library/Java/JavaVirtualMachines/temurin-17.jdk/Contents/Home/bin/java

/usr/libexec/java_home -v 17

Expected result:

/Library/Java/JavaVirtualMachines/temurin-17.jdk/Contents/Home

Step 5: Configure JAVA_HOME (permanent)

Open your shell profile file:

nano ~/.zshrc

Add at the end:

export JAVA_HOME=$(/usr/libexec/java_home -v 17)
export PATH=$JAVA_HOME/bin:$PATH

Reload:

source ~/.zshrc

Verify:

echo $JAVA_HOME

Expected result:

/Library/Java/JavaVirtualMachines/temurin-17.jdk/Contents/Home

🍎 macOS installation with SDKMAN! (alternative)

Install SDKMAN!

curl -s "https://get.sdkman.io" | bash
source "$HOME/.sdkman/bin/sdkman-init.sh"

List available Java 17 versions

sdk list java | grep tem

Result (example):

 Temurin       |     | 17.0.13      | tem    | installed  | 17.0.13-tem

Install

sdk install java 17.0.13-tem

Verify

java -version
which java
echo $JAVA_HOME

SDKMAN! Advantage

Allows installing multiple versions of Java and easily switching:

sdk use java 17.0.13-tem    # Use Java 17
sdk use java 21.0.5-tem     # Switch to Java 21
sdk default java 17.0.13-tem # Set Java 17 as default

🍎 Manual macOS installation (direct download)

Step 1: Download

1. Go to https://adoptium.net/
2. Select macOS → aarch64 (Apple Silicon M1/M2/M3) or x64 (Intel)
3. Download the .pkg file

Step 2: Install

Double-click the .pkg file and follow the wizard.

Step 3: Configure JAVA_HOME

echo 'export JAVA_HOME=$(/usr/libexec/java_home -v 17)' >> ~/.zshrc
echo 'export PATH=$JAVA_HOME/bin:$PATH' >> ~/.zshrc
source ~/.zshrc

Step 4: Verify

java -version
javac -version
which java
echo $JAVA_HOME

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Installation on Linux

🐧 Ubuntu / Debian (apt)

Step 1: Update packages

sudo apt update && sudo apt upgrade -y

Step 2: Install the JDK 17

Option A — OpenJDK from official repositories:

sudo apt install openjdk-17-jdk -y

Option B — Eclipse Temurin (recommended for uniformity):

sudo apt install -y wget apt-transport-https gpg

wget -qO - https://packages.adoptium.net/artifactory/api/gpg/key/public | \
  gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/adoptium.gpg > /dev/null

echo "deb https://packages.adoptium.net/artifactory/deb $(lsb_release -cs) main" | \
  sudo tee /etc/apt/sources.list.d/adoptium.list

sudo apt update
sudo apt install temurin-17-jdk -y

Step 3: Verify the installation

java -version

Expected result:

openjdk version "17.0.13" 2024-10-15
OpenJDK Runtime Environment Temurin-17.0.13+11 (build 17.0.13+11)
OpenJDK 64-Bit Server VM Temurin-17.0.13+11 (build 17.0.13+11, mixed mode, sharing)

javac -version

Expected result:

javac 17.0.13

Step 4: Verify the path

which java

Expected result:

/usr/bin/java

readlink -f $(which java)

Expected result (shows the real path):

/usr/lib/jvm/temurin-17-jdk-amd64/bin/java

Step 5: Configure JAVA_HOME

sudo nano /etc/environment

Add this line:

JAVA_HOME="/usr/lib/jvm/temurin-17-jdk-amd64"

Or for OpenJDK:

JAVA_HOME="/usr/lib/jvm/java-17-openjdk-amd64"

Reload:

source /etc/environment
echo $JAVA_HOME

Alternative — in ~/.bashrc

echo 'export JAVA_HOME=/usr/lib/jvm/temurin-17-jdk-amd64' >> ~/.bashrc
echo 'export PATH=$JAVA_HOME/bin:$PATH' >> ~/.bashrc
source ~/.bashrc

If multiple versions of Java are installed

sudo update-alternatives --config java

This displays all installed versions and allows you to choose:

There are 2 choices for the alternative java.

  Selection   Path                                            Priority  Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-21-openjdk-amd64/bin/java        2111      auto mode
  1            /usr/lib/jvm/java-17-openjdk-amd64/bin/java        1711      manual mode
  2            /usr/lib/jvm/java-21-openjdk-amd64/bin/java        2111      manual mode

Press <Enter> to keep the current choice[*] or type the selection number: 1

Same for javac:

sudo update-alternatives --config javac

🐧 Fedora / CentOS / RHEL (dnf/yum)

Fedora

sudo dnf install java-17-openjdk-devel -y

CentOS / RHEL

sudo yum install java-17-openjdk-devel -y

Verify

java -version
javac -version
which java

Configure JAVA_HOME

echo 'export JAVA_HOME=/usr/lib/jvm/java-17-openjdk' >> ~/.bashrc
echo 'export PATH=$JAVA_HOME/bin:$PATH' >> ~/.bashrc
source ~/.bashrc
echo $JAVA_HOME

Choose the active version

sudo alternatives --config java
sudo alternatives --config javac

🐧 Arch Linux / Manjaro (pacman)

sudo pacman -S jdk17-openjdk

Choose the active version

sudo archlinux-java status
sudo archlinux-java set java-17-openjdk

Verify

java -version
javac -version
which java
echo $JAVA_HOME

🐧 Installation with SDKMAN! (all distributions)

Install SDKMAN!

curl -s "https://get.sdkman.io" | bash
source "$HOME/.sdkman/bin/sdkman-init.sh"

Install Java 17

sdk list java | grep tem
sdk install java 17.0.13-tem

Verify

java -version
javac -version
which java
echo $JAVA_HOME

Manage multiple versions

sdk list java                      # See all available versions
sdk install java 21.0.5-tem        # Install Java 21 additionally
sdk use java 17.0.13-tem           # Use Java 17 for this session
sdk default java 17.0.13-tem       # Java 17 as default

🐧 Manual installation (direct download)

Step 1: Download

cd /tmp
wget https://github.com/adoptium/temurin17-binaries/releases/download/jdk-17.0.13%2B11/OpenJDK17U-jdk_x64_linux_hotspot_17.0.13_11.tar.gz

Step 2: Extract

sudo mkdir -p /usr/lib/jvm
sudo tar -xzf OpenJDK17U-jdk_x64_linux_hotspot_17.0.13_11.tar.gz -C /usr/lib/jvm

Step 3: Configure

echo 'export JAVA_HOME=/usr/lib/jvm/jdk-17.0.13+11' >> ~/.bashrc
echo 'export PATH=$JAVA_HOME/bin:$PATH' >> ~/.bashrc
source ~/.bashrc

Step 4: Verify

java -version
javac -version
which java
echo $JAVA_HOME

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Final verification (all OS)

Open a new terminal and run all these commands:

1. Java version

java -version

✅ Should display openjdk version "17.0.x"

2. Java compiler

javac -version

✅ Should display javac 17.0.x

3. Where is Java installed?

# macOS / Linux
which java
readlink -f $(which java)    # real path (Linux)

# Windows PowerShell
where.exe java

4. Is JAVA_HOME set?

# macOS / Linux
echo $JAVA_HOME

# Windows PowerShell
$env:JAVA_HOME

# Windows CMD
echo %JAVA_HOME%

✅ Should display a path to JDK 17

5. Quick test — compile and run a program

Create a file Hello.java:

public class Hello {
    public static void main(String[] args) {
        System.out.println("Java " + System.getProperty("java.version") + " is working!");
        System.out.println("JAVA_HOME = " + System.getProperty("java.home"));
    }
}

Compile and run:

javac Hello.java
java Hello

Expected result:

Java 17.0.13 is working!
JAVA_HOME = /Library/Java/JavaVirtualMachines/temurin-17.jdk/Contents/Home

Clean up:

rm Hello.java Hello.class

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Troubleshooting

❌ java is not recognized as a command

Cause	Solution
Java is not installed	Follow the installation steps above
PATH not configured	Add JAVA_HOME/bin to PATH
Terminal not reloaded	Close and reopen the terminal

Windows: Check that %JAVA_HOME%\bin is in the system PATH.

macOS/Linux: Check that your ~/.zshrc or ~/.bashrc contains:

export JAVA_HOME=...
export PATH=$JAVA_HOME/bin:$PATH

❌ Wrong Java version displayed

If java -version displays Java 8, 11, or 21 instead of 17:

Windows:

1. Check the PATH: version 17 should appear before others
2. Remove old versions from the PATH

macOS:

/usr/libexec/java_home -V          # List all versions
export JAVA_HOME=$(/usr/libexec/java_home -v 17)
java -version                       # Should now display 17

Linux:

sudo update-alternatives --config java    # Choose version 17
sudo update-alternatives --config javac

❌ JAVA_HOME is not set

Windows:

1. Start Menu → "environment variables"
2. System variables → New
3. Name: JAVA_HOME, Value: C:\Program Files\Eclipse Adoptium\jdk-17.0.13.11-hotspot

macOS:

echo 'export JAVA_HOME=$(/usr/libexec/java_home -v 17)' >> ~/.zshrc
source ~/.zshrc

Linux:

echo 'export JAVA_HOME=/usr/lib/jvm/temurin-17-jdk-amd64' >> ~/.bashrc
source ~/.bashrc

❌ Difference between java and javac

Command	Role	Included in
java	Run a compiled Java program	JRE and JDK
javac	Compile .java source code into .class	JDK only

If java works but not javac → you installed the JRE instead of the JDK. Reinstall the JDK.

❓ JDK vs JRE vs JVM — what's the difference?

┌─────────────────────────────────────┐
│              JDK                     │
│  (Java Development Kit)             │
│  ┌────────────────────────────────┐ │
│  │           JRE                  │ │
│  │  (Java Runtime Environment)    │ │
│  │  ┌──────────────────────────┐  │ │
│  │  │         JVM              │  │ │
│  │  │  (Java Virtual Machine)  │  │ │
│  │  │  Executes bytecode       │  │ │
│  │  └──────────────────────────┘  │ │
│  │  + Standard libraries         │ │
│  │  + java (run)                 │ │
│  └────────────────────────────────┘ │
│  + javac (compile)                 │
│  + jdb (debugger)                  │
│  + javadoc, jar, jshell...         │
└─────────────────────────────────────┘

Component	What it does	For whom
JVM	Executes Java bytecode	Everyone
JRE	JVM + libraries to run	End users
JDK	JRE + tools to develop (javac, jdb...)	Developers ← This is the one you need

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Validation checklist

Before moving on to the next TP (Maven Installation), check:

• java -version displays 17.0.x
• javac -version displays 17.0.x
• which java (or where.exe java) returns a valid path
• echo $JAVA_HOME (or $env:JAVA_HOME) is set
• The Hello.java program compiles and runs correctly

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Next Step

Java 17 is installed! Now proceed to the Maven installation:

➡️ Next TP: Installation of Maven 3.9.x

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⬅️ Back to Module 1