jvm-launcher

Tools to build a customized launcher executables for seamless experiences with JVM-based desktop applications.

Why?

Although Window icons and titles can be changed easily using common GUI libraries, many Java desktop application use the JVM's native launchers (java.exe or javaw.exe) to start the application. Neither of them are customizable which leads to a poor user experience when interacting with the application through the task manager and other system tools.

How?

This project implements a custom Java launcher using the JNI invocation API to launch a JVM. The launcher is small and can easily be compiled with custom resources to provide a seamless experience for end-users.

The launcher executable looks up a configuration file (config.toml) in its parent directory to determine all necessary information to start the JVM. A configuration file looks as follows:

libjvm_path = "./path/to/jvm.dll"
main_class = "com/example/Main"
jvm_args = [
    "-Djava.class.path=./path/to/application.jar;./path/to/library.jar"
]

Usage

Learn how to use the Gradle plugin to integrate building a custom launcher into an application's build process.

Building from source

Setup

This project uses Gradle's toolchain support to detect and select the JDKs required to run the build. Please refer to the build scripts to find out which toolchains are requested.

An installed JDK 1.8 (or later) is required to use Gradle.

Building

Once the setup is complete, invoke the respective Gradle tasks using the following command on Unix/macOS:

./gradlew <tasks>

or the following command on Windows:

gradlew <tasks>

Important Gradle tasks to remember are:

• clean - clean build results
• build - assemble and test the Java library
• publishToMavenLocal - build and install all public artifacts to the local maven repository

Additionally tasks may be used to print a list of all available tasks.

License

Copyright 2022-2025 Leon Linhart

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.