From their home page: "Launch4j is a cross-platform tool for wrapping Java applications distributed as jars in lightweight Windows native executables. The executable can be configured to search for a certain JRE version or use a bundled one, and it's possible to set runtime options, like the initial/max heap size. The wrapper also provides better user experience through an application icon, a native pre-JRE splash screen, a custom process name, and a Java download page in case the appropriate JRE cannot be found."
From their home page: "IzPack is an installer generator for the Java platform. It produces lightweight installers that can be run on any operating system where a Java virtual machine is available. The most common use is to distribute applications for the Java platform, but you can also use it for other kinds of projects. The main benefit of IzPack is that it provides a clean and unique way of distributing a project to users using different operating systems."