[jdt-core-dev] CompilationUnit outside classpath

["Philippe Mulet" <Philippe_Mulet@xxxxxxx>]

Currently the JavaModel tolerates managing units residing outside the
project classpath. As long as the corresponding resource exists, it will
pretend it exists, it can be opened and introspected.

This was intended to provide some minimal model support for such units,
which users could drag'n drop outside/back inside the project classpath.
However, this appears to be problematic since these elements are never
closed (unless client explicitly request it to be closed), and thus these
elements will leave in our element cache for ever...

This leak cannot be solved correctly, and we propose to instead prevent
opening such elements completely. We would only preserve existing behavior
for working copies (which are sharing the same ability), and for which the
closing is automatically done at the end of its life cycle.

Please shout if you don't agree with this resolution, we are currently
planning to implement these changes by 2.1-M3.