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Usage Guide

The Java Version Manager for Windows is designed to accommodate both casual developers and hardcore CI/CD engineers. It acts as both a visually guided Interactive TUI (Terminal User Interface) and a deeply powerful, highly-configurable Headless CLI.

This document outlines every command, flag override, and semantic route available in the engine.

🖥️ Interactive UI Mode

For the easiest, most visually appealing experience, you can rely entirely on the interactive menus.

To launch the main hub, simply run the tool from any terminal without arguments:

jvm

You can also launch it directly from:

  • Windows Terminal: Click the + dropdown menu and select Java Version Manager.
  • Start Menu: Search for Java Version Manager and press Enter.
  • Taskbar: Click the pinned DiamTek JVM icon.

From here, you can visually explore installed JDKs, fetch new versions, manage ecosystem tools, and change global settings. Exiting the menu automatically closes the dedicated terminal tab.

Initial Setup Note: If you have just downloaded the script manually, navigate to Settings (Global Command & Setup) (Option 3) and select Install Global Command (Option 1). Once installed globally, you can use the jvm command from anywhere on your system.

⚡ Quick-Switching (CLI)

You do not need to open the menu to change your active Java version. You can instantly update your JAVA_HOME and system PATH directly from the command line.

Basic Switching

Switch to a specific version globally:

jvm 21

Note: If there are multiple vendors installed for JDK 21 (e.g., Oracle and Adoptium), the engine will safely pause and prompt you to pick a vendor.

Semantic Target Routing

You don't need to memorize exact build numbers. You can speak to the tool semantically, and it will dynamically resolve the highest installed version that matches your request:

jvm latest
jvm lts

Architecture & Priority Overrides

You can chain flags to bypass prompts or override your global Settings for a single command.

Override the vendor prompt to silently select Adoptium:

jvm 21 --vendor adoptium

Force the engine to use Symlink Mode (UAC-Free Directory Junctions) for this specific switch, ignoring your saved default architecture:

jvm 21 --symlink

Force the engine to use Legacy Registry Mode (Requests Administrator UAC elevation) for this specific switch:

jvm 21 --legacy

Semantic routing combined with a vendor override (switches to the newest installed Amazon Corretto LTS version):

jvm lts --vendor corretto

True Session Isolation

If you only want to change the Java version for your current terminal window (without permanently altering your global Windows Registry or affecting background services), use the session flag:

jvm 21 --session

(Note: This feature requires the PowerShell Profile hook to be installed via the Settings menu).

📥 Headless Installations

The installation engine supports deep headless automation, allowing you to bypass menus incrementally—perfect for DevOps scripts and automated machine provisioning.

Interactive Installation

Open the Installation Wizard UI:

jvm install

Semi-Automated Installation

Initiate the installation of JDK 21 (the engine will pause to prompt you for your preferred Vendor):

jvm install 21

Prompts you to pick an LTS version (e.g., 17, 21, 25) and then prompts you for your preferred Vendor:

jvm install lts

Locks onto the highest available LTS version, but still pauses to ask which Vendor you want:

jvm install lts --latest

100% Fully Automated (CI/CD)

Bypass all prompts to silently download and install Oracle JDK 21:

jvm install 21 --vendor oracle

Silently resolve, download, and install the absolute newest Oracle LTS version without a single prompt:

jvm install lts --latest --vendor oracle

The Aggressive Override (-y / --yes) If you are running in a strict CI/CD pipeline, you can pass -y to aggressively bypass any remaining interactive safety warnings (such as Oracle's legacy version caps, or "already installed" overwrite warnings) for 100% uninterrupted automation:

jvm install 17 --vendor oracle -y

📦 Ecosystem Build Tools (SDKMAN! Parity)

JVM supports downloading, switching, and managing modern build tools natively alongside Java. You can manage these via the command line or through the interactive Ecosystem Management sub-menu.

Install the absolute newest version of Maven directly from Apache:

jvm install maven latest

Install a specific legacy version of Gradle:

jvm install gradle 8.9

Instantly switch your active KOTLIN_HOME (and system PATH) to the specified version:

jvm kotlin 2.0.20

Safely uninstall a specific tool and cleanly scrub its environment variables from your registry:

jvm uninstall groovy 4.0.23

🔄 Updates & Uninstalls

Updating Tools

Open the dynamic, vendor-sorted Updater menu UI:

jvm update

Bulk Updating: Silently check and automatically patch all installed JDKs and Ecosystem Tools (Maven, Gradle, etc.) to their absolute newest releases:

jvm update --all

Silently check and automatically patch only your installed Oracle JDKs:

jvm update --all --vendor oracle

Uninstalling Tools

Open the dynamic, vendor-sorted Uninstaller menu UI:

jvm uninstall

Headless uninstallation for JDK 21. If multiple vendors are found for the same version, it safely pauses to ask you which vendor you want to remove:

jvm uninstall 21

100% headless uninstallation specifically targeting the Oracle vendor (bypasses all prompts):

jvm uninstall 21 --vendor oracle

📂 Directory-Based Auto-Switching

Instantly configure a project's required environment by simply running the tool inside any directory containing a .java-version or SDKMAN .sdkmanrc file.

Silently parse the file and auto-switch to that version locally for the current terminal only:

jvm

Parse the file and force the version switch to apply globally to your system registry:

jvm --global

Syntax: .java-version

Your .java-version file can specify a standard build number:

21

It can also contain advanced inline CLI flags to lock specific vendors or architecture modes on a strict per-project basis. Make sure the version and flags are all on a single line:

21 --vendor adoptium --legacy

Syntax: .sdkmanrc (Hijacking)

If you are collaborating with developers on Linux/macOS, this tool natively reads their .sdkmanrc files. It dynamically maps SDKMAN vendor strings (like 17-tem or 21-amzn) to your native Windows JDKs and isolates all required ecosystem tools for that session.

java=21-tem
maven=3.9.6
gradle=8.5
kotlin=1.9.22

🧹 Global Environment Management

Inspection Commands

List all installed JDKs with their version, vendor, and path. The currently active JDK is highlighted with [ACTIVE]. (Scroll to the bottom to see installed Ecosystem tools).

jvm list

Display the exact path your current JAVA_HOME environment variable is pointing to:

jvm env

System Scrubbing

Instantly wipe JAVA_HOME and purge Java from your Windows PATH entirely:

jvm clear

Bring Your Own JDK (BYO-JDK)

Manually link an existing, custom JDK directory (or GraalVM native image) into the manager. Linked JDKs automatically integrate into the interactive UI under the "Custom (Local Links)" category:

jvm link C:\my-custom-jdk my-jdk

Remove a custom linked JDK from the manager:

jvm unlink my-jdk

Self-Updating

Display your current jvm.bat build number and compare it against the latest release on GitHub to check for engine updates:

jvm version

Automatically download and atomic-swap the core jvm.bat script if a newer version is available on GitHub:

jvm self-update

Self-Uninstallation

Launch the deep uninstallation process directly from the CLI to wipe JVM, environment variables, AppData caches, and installed tools:

jvm self-uninstall

Help & Command Reference

Display the full command-line reference, arguments, and flag overrides directly in your terminal:

jvm --help
# Or: jvm help, jvm -h, jvm /?