# Installing OpenJDK with SDKMAN in Linux

### Installing SDKMAN

* Installing `SDKMAN` allows for easy installation and version switching of **OpenJDK**.
    

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

### Installing OpenJDK 21

* This is an example of installing `OpenJDK 21`, the most current **LTS** version.
    

```bash
# Install Amazon Corretto 21 and set as the default JDK
$ sdk i java 21.0.2-amzn
$ sdk default java 21.0.2-amzn

# Check installed version
$ java --version
openjdk 21.0.2 2024-01-16 LTS
```

### Switching between OpenJDK 17 and 21

* In a local development environment, there may be a need to switch between different versions of **OpenJDK** for different projects. This can be easily done by executing the `sdk default java {identifier}` command.
    

```bash
# Install Amazon Corretto 17
$ sdk i java 17.0.10-amzn

# Switch to OpenJDK 17
$ sdk default java 17.0.10-amzn
$ java --version
openjdk 17.0.10 2024-01-16 LTS

# Switch back to OpenJDK 21
$ sdk default java 21.0.2-amzn
$ java --version
openjdk 21.0.2 2024-01-16 LTS

# Create Aliases for quick and convenient transitions
$ nano ~/.bash_aliases
alias java17="sdk default java 17.0.10-amzn; java --version"
alias java21="sdk default java 21.0.2-amzn; java --version"
```

### Installing Kscript

* Additionally, installing `kscript` allows for the creation of shell scripts using **Kotlin**.
    

```bash
# Install kscript
$ sdk install kotlin
$ sdk install kscript
$ sdk install springboot
```