Gentoo Java 1.5 FAQ
Why was Java 1.5 hard-masked for so long?
Java 1.5 was hard masked forever because there were a number of issues which
made it unsafe to use a 1.5 JDK as your system VM.
The first issue with Java 1.5 was backwards compatibility. If
you compile packages with a 1.5 JDK, the default behavior is that
the compiled classes can only be used in a 1.5 or above VM.
The other significant issue is that there are packages which are not
compatible with JDK 1.5, as they currently exist in the portage tree. For
example, several abstract classes and interfaces now have new abstract
methods in 1.5. This means that packages would need to be patched to
override these abstract methods. Failing that, you could also try using
1.4 to compile the offending package. However, due to the backwards
compatibility problem mentioned above, you wouldn't be able to use
external libraries, because they were compiled only for 1.5.
What is the status of Java 1.5?
The good news is that work is that support for 1.5 is here!
To begin using it, you will need to follow the upgrade guide.
The Java documentation has been updated for the usage of this new system,
and is available at:
Additional material can be found at the following, under the
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