Alternative to fatJar - modular solution?

Glavo zjx001202 at
Wed Oct 6 17:24:44 UTC 2021

For a long time, unpacking and repackaging all dependencies into a file
called fatJar was the first choice for single file distribution of Java
programs. However, the compatibility of this solution with JPMS is very
poor - it breaks up all the modules and works with classpath.

I think many programmers may expect JDK to provide a native lightweight
solution that bundles multiple modules into a single file. From users'
enthusiasm for fatjar, we can see that they have a keen demand for such
a format. jlink and jpackage cannot solve the problem that fatjar wants
to solve. We now have the jimage file format, but it seems that it is
only the internal format of JDK and is only used in the modules file.

The lack of such a solution has caused us some trouble about whether to
modularize. So I earnestly request JDK to add support for such a file

  1. It can bundle multiple modules in one file (It may be based on jimage
  or other compression/archive format).

  2. It should only bundle application dependencies without carrying JDK
  standard library or even complete JRE.

  3. It should have a manifest file like the MANIFEST.MF for jar,
  allows we to add descriptions of entry points, Add-Opens, module path,
  and so on.

  4. Allows simple execution, such as `java -jimage foo.jimage`. In
  this case, use the contents described in the above manifest file.

  5. Associate this file format during JDK/JRE installation, and
  execute it in the above manner when double clicking it.

  6. Like the ZIP (JAR) format, allow other content to be appended
  before its content. This makes it easy to attach a launcher (usually
  exe or bash) before its content.

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