JEP 220: Modular Run-Time Images

mark.reinhold at mark.reinhold at
Fri Oct 31 16:40:43 UTC 2014

2014/10/30 4:17 -0700, mark.reinhold at
> The JAR format has run its course.  It's time to move on.

Apparently this statement has been taken out of context, so allow me to

We're not proposing to eliminate JAR files in general, but merely to
stop using them inside the JRE and the JDK.

This will affect a small class of applications, mainly IDEs and other
kinds of development tools that need to enumerate and inspect the
classes stored in a run-time image.  JEP 220 proposes a new mechanism by
which they can do that, and in a way that's immune to future internal
format changes.

Existing JAR-based libraries and applications will continue to work
fine.  The JAR format, despite its numerous flaws, is here to stay and
will likely be a supported packaging and distribution format until the
end of time.  We even plan to make it possible to package true modules
as JAR files, for ease of migration and distribution.

- Mark

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