Introduction

SDKBOY is a graphical user interface for managing Software Development Kits (SDKs) through SDKMAN!. It provides an intuitive way to browse, install, uninstall, and switch between different versions of development tools like Java, Gradle, Maven, and many others.

What is SDKMAN!?

SDKMAN! is a command-line tool for managing parallel versions of multiple Software Development Kits on most Unix-based systems. SDKBOY provides a user-friendly graphical interface to all SDKMAN! functionality.

System Requirements

  • SDKMAN! installed and configured

  • Operating system supported by SDKMAN! (Unix-based systems)

Getting Started

First Launch

When you first launch SDKBOY, the application will:

  1. Connect to the SDKMAN! API

  2. Load the list of available SDKs (candidates)

  3. Display them in the left panel

Main Interface

The SDKBOY interface consists of three main areas:

Left Panel - Candidates

Lists all available SDKs (Java, Gradle, Maven, etc.) with the number of installed versions for each.

Right Panel - Versions

Shows all available versions for the selected SDK, with installation status and other details.

Shortcut Panel (Optional)

Displays keyboard shortcuts and application information. Toggle with Alt+S or the "?" button.

Working with SDKs

Browsing Available SDKs

The left panel shows all available SDKs (called "candidates" in SDKMAN!):

  • Name: The SDK name (e.g., "Java", "Gradle")

  • Installed: Number of versions currently installed

Filtering SDKs:

  • Use the filter field at the bottom to search by name

  • Check "Installed" to show only SDKs with installed versions

  • Use Up/Down arrow keys to navigate the list

Managing Versions

Select an SDK from the left panel to view its versions in the right panel.

Version Information:

  • Vendor: Provider of the version (visible for Java)

  • Version: Version number or identifier

  • Installed: ✓ if the version is installed locally

  • Downloaded: ✓ if the version is downloaded but not installed

  • Used: ✓ if this is the currently active global version

Filtering Versions:

  • Filter field: Search by version number or vendor name

    • Multiple terms are supported: tem 24 finds "Temurin 24.x"

    • Partial matching: 24 7 finds both "24.0.7" and "24.7.0"

  • Installed: Show only installed versions

  • Downloaded: Show only downloaded versions

  • Used: Show only the currently active version

Installing Versions

To install an SDK version:

  1. Select the SDK from the left panel

  2. Select the desired version from the right panel

  3. Use one of these methods:

    • Press Alt+I or Alt+Insert

    • Double-click an uninstalled version

    • Right-click and select Install (if available)

Installation Process:

  1. If not downloaded, the version will be downloaded first

  2. Progress bar shows download and extraction progress

  3. Press Escape or click "Cancel" to cancel during download

  4. Once complete, the version becomes available for use

Setting Active Version

To set a version as your global default:

  1. Select the installed version

  2. Use one of these methods:

    • Press Alt+U

    • Double-click an installed (but not used) version

    • If the version isn’t installed, it will be installed first

The active version will be marked with ✓ in the "Used" column.

Uninstalling Versions

To remove an installed version:

  1. Select the installed version

  2. Use one of these methods:

    • Press Alt+D or Alt+Delete

    • Double-click the currently used version

    • Right-click and select Uninstall (if available)

You can uninstall the currently active version. The system will revert to the previously used version or system default.

Copying Use Commands

To get the SDKMAN! command for setting a version:

  1. Select any version (installed or not)

  2. Press Alt+C

  3. The command (e.g., sdk use java 11.0.12-open) is copied to your clipboard

  4. If the version isn’t installed, it will be installed first

Keyboard Shortcuts

SDKBOY is designed for efficient keyboard operation:

Global Shortcuts

Shortcut Action

Alt+R

Refresh candidates and versions

Alt+P

Open preferences

Alt+S

Toggle shortcut panel

Alt+X

Exit application

Escape

Cancel current operation

Filter Shortcuts

Shortcut Action

Alt+T

Toggle "Installed" filter (Candidates)

Alt+N

Toggle "Installed" filter (Versions)

Alt+A

Toggle "Downloaded" filter

Alt+E

Toggle "Used" filter

Navigation

Shortcut Action

Enter

Switch focus between candidate and version filter fields

Up

Previous item (wraps to bottom)

Down

Next item (wraps to top)
Selection starts empty. Press Down to select the first item or Up to select the last item.

Version Management

Shortcut Action

Alt+I / Alt+Insert

Install selected version

Alt+D / Alt+Delete

Uninstall selected version

Alt+U

Use selected version

Alt+C

Copy use command to clipboard

Double-Click Actions

Double-clicking a version performs different actions based on its status:

  • Uninstalled version: Install

  • Installed version: Use (set as active)

  • Used version: Uninstall

Preferences

Access preferences with Alt+P or the Preferences menu.

General Settings

Confirm Actions (Alt+I)

When enabled, shows confirmation dialogs before install, uninstall, and use operations.

Confirm Exit (Alt+X)

When enabled, asks for confirmation before closing the application.

Archive Tools

Configure paths to archive extraction tools:

Zip Path (Alt+Z)

Path to zip executable for handling .zip archives.

Unzip Path (Alt+U)

Path to unzip executable for extracting .zip archives.

Tar Path (Alt+T)

Path to tar executable for handling .tar.gz archives.

Use the folder button next to each field to browse for the executable.

Advanced Settings

Keep Downloads Available (Alt+K)

When enabled, downloaded archives are kept after installation for faster reinstallation.

Log Level (Alt+V)

Controls the verbosity of application logging. Use the buttons to open log files (Alt+F) or the log directory (Alt+D).

Look & Feel (Alt+L)

Choose the application’s visual theme.

Tips and Best Practices

Efficient Workflow

  1. Use filters: Narrow down large lists with the filter fields

  2. Keyboard navigation: Learn the shortcuts for faster operation

  3. Use Enter key: Quickly switch between candidate and version filters

  4. Check versions: Use the "Used" filter to quickly see your active versions

Managing Disk Space

  • Use "Keep Downloads Available" sparingly if disk space is limited

  • Regularly uninstall unused versions

  • Monitor the "Downloaded" column to see what’s cached locally

Working with Java

  • The vendor column is automatically shown for Java versions

  • Popular vendors include OpenJDK, Oracle, Amazon Corretto, GraalVM

  • Consider your project requirements when choosing between vendors

Troubleshooting

Common Issues

No SDKs appear in the list

  • Check that SDKMAN! is properly installed and in your PATH

  • Verify internet connectivity

  • Try refreshing with Alt+R

Installation fails

  • Check available disk space

  • Verify archive tool paths in preferences

  • Check log files for detailed error information

Version not available for use

  • Ensure the version completed installation successfully

  • Some versions may require manual configuration

Application won’t start

  • Check that SDKMAN! is properly configured

  • Review application logs

Getting Help

  • Use Alt+S to show the shortcut panel with keyboard shortcuts and about information

  • Check log files through Preferences → Log Level → Open Log File

  • Visit the SDKBOY GitHub repository for issues and updates

  • Consult SDKMAN! documentation for SDK-specific questions

Advanced Usage

SDKMAN! Home Directory

SDKBOY uses the default SDKMAN! home directory (~/.sdkman/). Custom locations are not currently supported.

Integration with IDEs

After setting a version with SDKBOY:

  1. Restart your terminal or source your shell profile

  2. Verify the change with java -version or the appropriate command

  3. Some IDEs may need to be restarted to recognize the new version

Command Line Equivalent

SDKBOY operations correspond to these SDKMAN! commands:

SDKBOY Action SDKMAN! Command

Install

sdk install <candidate> <version>

Uninstall

sdk uninstall <candidate> <version>

Use

sdk use <candidate> <version>

List candidates

sdk list

List versions

sdk list <candidate>

Appendices

Supported SDKs

SDKBOY supports all SDKs available through SDKMAN!, including but not limited to:

  • JVMs: Java, GraalVM

  • Build Tools: Maven, Gradle, SBT, Mill

  • Languages: Kotlin, Scala, Groovy

  • Frameworks: Spring Boot CLI, Micronaut

  • Cloud Tools: Google Cloud SDK

  • **And many more!

File Locations

SDKMAN! Home: ~/.sdkman/

Downloaded Archives: ~/.sdkman/archives/

Installed Versions: ~/.sdkman/candidates/<candidate>/<version>/

Configuration: ~/.sdkman/etc/config

Version History

This manual corresponds to SDKBOY version 1.0.

For the latest updates and changes, visit the project repository.

Copyright © Björn Darri Sigurðsson. Licensed under GPL v3.

Source code: https://github.com/codion-is/sdkboy