[news.eclipse.technology.m2e] Eclipse errors after SCM update

[Yves Schumann <starwarsfan@xxxxxxxxxx>]

Hello

After migrating an application from Ant build to Maven build I ran into
some problems. The original application consists of around 20 eclipse
projects from which Ant creates three *.war files, so three
webapplications. The amount of functionality of these application should
be increased a lot in the next time but there are a lot of problems with
Ant, so we decide to migrate the projects to use Maven. That's the
history. ;-)

After a lot of cleanup and migration work these projects were split up
into around the double amount of eclipse projects using m2e.
Additionally I've created a plain project which is only used for
configuration, i. e. profiles, dependency management a.s.o. This
configuration project is referenced from nearly all other projects as
parent project. Maybe this is not the final solution but currently this
setup works fine using plain Maven.

The problems begin with m2e and our development behaviour. Development
is done feature based which means, that we have different branches on
our SCM (which is ClearCase) for each feature. After a lot of tests
(like integration tests, system tests, ...) these branches are merged
into the release branch. Additionally some of these feature branches
were merged together in both directions every two or three days, because
they require each other but development can't be done on one branch.
Currently not the best solution but I'm not in the position to change
this. Maybe it can be done step by step...

One of the major problems for us is, that after an update from SCM
Eclipse shows a huge amount of resolving errors but maven build runs
successfully through without any errors. Additionally confusing the
fact, that this happens mostly on different developers but not all of
them!? After digging into possible solutions I've modified "Goals to
invoke after project clean" on every project and entered "clean compile
test-compile" there. But this helps not really during or after an update
out of SCM, the errors mostly still there on Eclipse, even after running
Eclipse clean.

Now I'm uninspired what to do. :-/ One guess is that this has to do with
Eclipse's own history inside the workspace metadata. Does anyone know
how to clear this history? This history is growing over time but in my
or our case not really necessary because everything is under version
control.

Oh, there is another thing I can mention here: Eclipse hangs without any
reaction if I try to import a lot of projects at once. Nothing happens
and the percentage counter "Updating Maven Dependencies" on the bottom
of the screen freezes. So the creation of a new workspace is very sad
because with one import step only a small amount of projects can be
importet. It works best for us, if with every import step only three or
four projects are imported. The import is done using the default Eclipse
project importer. The Maven project importer can't be used because it
shut down Eclipse completely sometimes/often. Otherwise the behaviour is
the same as described above.

All this is done with installed JRE/JDK 6u12, Eclipse 3.4.2
(M20090111-1700) and m2e 0.9.6 because 0.9.7 has a problem with the
creation of web projects (If I remember right something with the
creation/compression of the *.war file). If this is solved I can try an
update but this a definitive requirement for our developers and the
reason to stay on 0.9.6. Please let me know if I can (or should) try an
update of separate m2e components, but the build of web projects is a
must for us at the moment.

Wow, a lot of text! Would be nice if someone can read it and possibly
give me a hint. Thx a lot in advance.

Regards,
Yves
-- 
Arbeiten am Computer ist wie U-Boot fahren. Fängt man an die Fenster zu
öffnen, dann gehen die Probleme los.