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Build Status Apache License Java-9+ Maven Release Gitter

Read the documentation, explore the JavaDoc, or see it in action

Create a framework: design the environment and lifecycle (—bootstrap) to make your own auto-update framework and hack it to the core, or use the built-in default bootstrap.



Using the default bootstrap, downloads 4 files then launches hello-world.jar. You can see that subsequent runs won't download again.



Using a custom bootstrap implemented to report progress in JavaFX, downloads 4 files then launches hello-world.jar.



Update4j is the first auto-update and launcher library designed for Java 9+. Easily host your application files anywhere (even Google Drive, Dropbox, Amazon S3, or Maven Central) and you can synchronize them with all your distributed applications. You can use any protocol you wish to retrieve those files and may be protected under authenticated API.

In update4j you have ultimate control of every process, from startup - update - launch - shutdown, since it's a library (you call the 3rd party code) not a framework (3rd party calls your code outside your control). In addition, every single piece of code is completely updatable; even update4j itself, once a new version is released! (Well, if you properly set up the environment.)

Installation & Usage

You can download or install using Maven:


You can use it as a regular dependency, or you may run it as a runnable JAR file.

To run it in the modulepath, use either of:

$ java -p update4j-1.5.9.jar -m org.update4j
$ java -p . -m org.update4j

To run it in the classpath, use either of:

$ java -jar update4j-1.5.9.jar
$ java -cp * org.update4j.Bootstrap

For more information refer to Starting the Application in the wiki.

What's New in 1.5.x — Migration Guide

  • New update model Configuration.update(ArchiveUpdateOptions), using an Archive to store update files, it can then be 'installed' (calling Archive::install). #76
  • Deprecated previous update models, but still available for smooth migration.
  • Improved update return value as UpdateResult. #87
  • Using the DefaultLauncher, not passing default.launcher.main.class will run the command-line arguments as a script. #88
  • ignoreBootConflict no longer required if there are no user modules on the boot module layer.
  • DefaultBootstrap::updateFirst now performs update in parallel while launching the business app. #104
  • Support Elliptic Curve cipher. #89
  • Clamp update handler frac values between 0 and 1. #106


Basil Inc


This project is licensed under the Apache Software License 2.0