jwmv — Java Version Manager for Windows

A fast, lightweight CLI tool to install, manage, and switch between multiple Java (JDK) versions on Windows. Built with .NET 8, inspired by tools like SDKMAN! and nvm.

Features

• Install any JDK — Temurin, Zulu, GraalVM, Microsoft, Corretto, Liberica, SAP, Oracle and more via Foojay Disco API
• Switch versions instantly — per-session, per-project (.jwmvrc), or set a persistent default
• Shell integration — PowerShell profile bootstrap for automatic version switching
• Self-update — update jwmv itself from GitHub Releases
• Diagnostics — doctor command detects PATH conflicts and misconfigurations
• Single-file executable — no runtime dependencies, just download and run
• Windows x64 & ARM64 support

Installation

winget (recommended)

winget install stescobedo92.jwmv

npm

npm install -g @stescobedo9205/jwmv

Downloads the native binary for your architecture automatically. No .NET runtime needed.

.NET global tool

dotnet tool install -g jwmv

Requires the .NET 8 runtime.

Download from GitHub Releases

# Download the latest release for your architecture
# https://github.com/stescobedo92/jwmv/releases

# Extract and place jwmv.exe somewhere in your PATH, for example:
Expand-Archive jwmv-win-x64.zip -DestinationPath "$HOME\.jwmv\bin"

# Add to PATH (run once)
[Environment]::SetEnvironmentVariable(
    "Path",
    "$HOME\.jwmv\bin;" + [Environment]::GetEnvironmentVariable("Path", "User"),
    "User"
)

Quick Start

# See what's available
jwmv list

# Install Java 21 (Temurin) and set it as default
jwmv install 21-tem --default

# Verify
jwmv current
java -version

# Install another version
jwmv install 17-zulu

# Switch for this session
jwmv use 17-zulu

Commands

jwmv list [filter]

List available JDK distributions from the Foojay catalog.

# List all available JDKs
jwmv list

# Filter by major version
jwmv list 21

# Filter by distribution
jwmv list tem

# Filter by version + distribution
jwmv list 17-zulu

# Force catalog refresh
jwmv list --refresh

Aliases: ls

| Option | Description | |-----------------|------------------------------------| | [filter] | Optional version/distribution filter | | -r, --refresh | Force refresh the catalog cache |

jwmv install [identifier]

Install a JDK version. Runs interactively if no identifier is provided.

# Interactive mode — prompts for filter and selection
jwmv install

# Install a specific version
jwmv install 21-tem

# Install and set as the default JAVA_HOME
jwmv install 21.0.4-tem --default

# Install with forced catalog refresh
jwmv install 17-zulu --refresh

| Option | Description | |-----------------|--------------------------------------------| | [identifier] | Version identifier (e.g. 21-tem, 17-zulu) | | -d, --default | Set as default JAVA_HOME after install | | -r, --refresh | Force refresh the catalog before install |

Identifier format: <version>-<distribution> where distribution is a short alias:

| Alias | Distribution | |-----------|---------------------| | tem | Eclipse Temurin | | zulu | Azul Zulu | | ms | Microsoft OpenJDK | | graalvm | GraalVM Community | | cor | Amazon Corretto | | lib | Liberica | | sap | SAP Machine | | ojdk | Oracle OpenJDK | | oracle | Oracle JDK |

jwmv uninstall [identifier]

Remove an installed JDK version.

# Interactive selection
jwmv uninstall

# Remove a specific version
jwmv uninstall 17-zulu

Aliases: remove, delete, rm

jwmv installed

List all locally installed JDK versions.

jwmv installed

Aliases: local

jwmv use <identifier>

Activate a JDK for the current shell session. Does not modify the persistent default.

# Switch to Java 17 for this session
jwmv use 17-zulu

# Specify shell explicitly
jwmv use 21-tem --shell powershell

Note: When running as an executable, use emits a PowerShell script to stdout. For seamless switching, set up shell integration.

| Option | Description | |------------------|-------------------------------| | <identifier> | Version to activate (required) | | --shell <SHELL> | Target shell (default: powershell) |

jwmv default <identifier>

Set the persistent default JAVA_HOME for all new shell sessions.

# Set Java 21 Temurin as the system-wide default
jwmv default 21-tem

This updates the Windows User environment variables (JAVA_HOME, PATH) and broadcasts the change so new terminals pick it up immediately.

jwmv current

Show the currently active Java version and how it was resolved.

jwmv current

Output shows:

• Active version alias
• Resolution source: Default, Session, or Project
• Resolved JAVA_HOME and bin paths
• Project .jwmvrc path (if applicable)

jwmv home [identifier]

Print the JAVA_HOME path for a version. Useful for scripting.

# Current JAVA_HOME
jwmv home

# JAVA_HOME for a specific version
jwmv home 17-zulu

# Use in scripts
$env:JAVA_HOME = $(jwmv home 21-tem)

jwmv upgrade [identifier]

Upgrade installed JDK(s) to the latest patch in the same major/vendor track.

# Upgrade a specific installation
jwmv upgrade 21-tem

# Upgrade all installed versions
jwmv upgrade

jwmv update

Refresh the local catalog cache from the Foojay API.

jwmv update

The catalog is cached locally and auto-refreshes every 6 hours (configurable). Use this to force an immediate refresh.

jwmv doctor

Run diagnostics to detect common issues.

jwmv doctor

Checks for:

• JAVA_HOME correctness
• PATH conflicts (e.g. system Java taking precedence)
• PowerShell profile integration status
• java.exe resolution via where.exe

jwmv config

Display the current jwmv configuration.

jwmv config

Shows: root directory, config file path, preferred distribution, catalog refresh interval, auto-env setting, default shell, and self-update repository.

jwmv integrate

Install the PowerShell profile hook for automatic version switching.

# Auto-detect profile
jwmv integrate

# Specify shell
jwmv integrate --shell powershell

# Custom profile path
jwmv integrate --profile "C:\Users\me\Documents\PowerShell\Microsoft.PowerShell_profile.ps1"

| Option | Description | |---------------------|---------------------------------| | --shell <SHELL> | Target shell (default: powershell) | | --profile <PATH> | Custom profile file path |

jwmv env

Print environment activation scripts or show project configuration.

# Show project .jwmvrc
jwmv env

# Emit initialization script
jwmv env --init

# Emit for a specific directory
jwmv env --cwd ./my-project

| Option | Description | |------------------|-----------------------------------------| | --shell <SHELL> | Target shell | | --cwd <PATH> | Working directory to scan for .jwmvrc | | --init | Emit shell initialization script |

jwmv flush

Clear cached files selectively.

# Clear downloaded archives
jwmv flush --archives

# Clear temporary files
jwmv flush --temp

# Clear catalog cache
jwmv flush --catalog

# Clear everything
jwmv flush --archives --temp --catalog

| Option | Description | |---------------|----------------------------------| | --archives | Delete downloaded ZIP archives | | --temp | Delete temporary extraction files | | --catalog | Delete the catalog cache |

jwmv selfupdate

Update jwmv itself from GitHub Releases.

# Check for updates
jwmv selfupdate --check

# Apply update
jwmv selfupdate

# Skip confirmation
jwmv selfupdate --yes

# Force reinstall current version
jwmv selfupdate --force

# Update and restart
jwmv selfupdate --restart

# Use a different repository
jwmv selfupdate --repository owner/repo

Aliases: self-update

| Option | Description | |---------------------------|------------------------------------------| | -c, --check | Only check, don't apply | | -f, --force | Force update even if same version | | -y, --yes | Skip confirmation prompt | | --restart | Restart jwmv after update | | -r, --repository <REPO> | GitHub owner/repo for releases | | -t, --tag <TAG> | Specific release tag to install |

Shell Integration

jwmv can automatically switch Java versions when you cd into a project with a .jwmvrc file.

Setup

jwmv integrate

This adds a managed block to your PowerShell profile ($PROFILE) that bootstraps jwmv on every new terminal session. The integration:

1. Reads the current or project-specific Java version
2. Sets JAVA_HOME and PATH automatically
3. Switches versions seamlessly as you navigate between projects

Manual integration

Add this to your PowerShell profile ($PROFILE):

# >>> jwmv initialize >>>
$jwmvInit = & jwmv env --init --shell powershell 2>$null
if ($jwmvInit) { $jwmvInit | Invoke-Expression }
# <<< jwmv initialize <<<

Per-Project Java Version

Create a .jwmvrc file in your project root:

21-tem

When shell integration is active, jwmv automatically activates this version when you enter the directory. The resolution order is:

1. Session — set via jwmv use
2. Project — from .jwmvrc (walks up the directory tree)
3. Default — set via jwmv default

Configuration

jwmv stores its data under ~/.jwmv/:

~/.jwmv/
├── config.json          # User configuration
├── candidates/
│   └── java/            # Installed JDKs
├── archives/            # Downloaded ZIP files
├── tmp/                 # Temporary extraction files
└── var/
    ├── catalog.json     # Cached Foojay catalog
    └── manifests/
        └── java/        # Installation metadata (one JSON per version)

config.json

{
  "preferredDistributionAlias": "tem",
  "catalogRefreshHours": 6,
  "autoEnvEnabled": true,
  "defaultShell": "powershell",
  "defaultJavaAlias": "21-tem",
  "selfUpdateRepository": "stescobedo92/jwmv"
}

| Key | Default | Description | |-----------------------------|----------------|----------------------------------------------| | preferredDistributionAlias | "tem" | Default distribution when not specified | | catalogRefreshHours | 6 | Hours before catalog auto-refreshes | | autoEnvEnabled | true | Enable .jwmvrc auto-switching | | defaultShell | "powershell" | Shell for script generation | | defaultJavaAlias | — | Persistent default Java version | | selfUpdateRepository | — | GitHub owner/repo for self-update |

Usage Examples

Managing a multi-project workflow

# Project A needs Java 17
cd C:\Projects\legacy-app
echo "17-cor" > .jwmvrc

# Project B needs Java 21
cd C:\Projects\modern-api
echo "21-tem" > .jwmvrc

# Install both versions
jwmv install 17-cor
jwmv install 21-tem --default

# With shell integration, Java switches automatically
cd C:\Projects\legacy-app
java -version   # → Corretto 17

cd C:\Projects\modern-api
java -version   # → Temurin 21

Architecture

Jwmv.Cli            → Spectre.Console CLI commands and DI setup
Jwmv.Core            → Interfaces, models, utilities (no dependencies)
Jwmv.Infrastructure  → Foojay API client, storage, Windows integration
Jwmv.Tests           → XUnit tests

The project follows a clean architecture pattern with dependency inversion. All services are behind interfaces and injected via Microsoft.Extensions.DependencyInjection.

Building & Testing

# Restore
dotnet restore

# Build
dotnet build -c Release

# Test
dotnet test

# Publish single-file executable
dotnet publish src/Jwmv.Cli -c Release -r win-x64 --self-contained -p:PublishSingleFile=true -p:EnableCompressionInSingleFile=true

License

This project is open source. See the repository for license details.