Java Development Notes

This document contains notes and guides related to Java development.

SDKMAN

SDKMAN is a tool for managing parallel versions of multiple Software Development Kits on most Unix-like systems. It’s particularly useful for managing different versions of Java, Scala, Groovy, and other JVM-based languages.

Installation

Install SDKMAN:
```
curl -s "https://get.sdkman.io" | bash
```
After running this, follow the instructions on the screen, which will likely involve sourcing a script in your shell profile.
Check the version to verify the installation:
```
sdk version
```
Update SDKMAN to the latest version:
```
sdk selfupdate force
```

Usage

Managing SDKs

List all available SDKs:
```
sdk list
```
List available versions of a specific SDK (e.g., Java):
```
sdk list java
```
Install the latest stable version of an SDK:
```
sdk install java
```
Install a specific version:
```
sdk install java 17.0.2-tem
```
Uninstall a version:
```
sdk uninstall java 17.0.2-tem
```

Switching Between Versions

Use a specific version in the current shell: This change is only active for the current terminal session.
```
sdk use java 11.0.12-tem
```
Set a default version for all new shells:
```
sdk default java 11.0.12-tem
```
Check the currently used version:
```
sdk current java
```

Project-Specific Java Version

You can define a specific Java version for a project, so you don’t have to manually switch every time you work on it.

Navigate to your project’s root directory.
Create a .sdkmanrc file. You can do this manually or by running:
```
sdk env init
```
Add the desired Java version to the .sdkmanrc file:
```
# .sdkmanrc
java=21.0.4-tem
```

Now, whenever you cd into this directory, SDKMAN will automatically prompt you to use the specified Java version if it’s not already active.