Currently there is no way to determine the precise changes done
to the working tree by a JGit command. Only the CheckoutCommand
actually provides access to the lists of modified, deleted, and
to-be-deleted files, but those lists may be inaccurate (since they
are determined up-front before the working tree is modified) if
the actual checkout then fails halfway through. Moreover, other
JGit commands that modify the working tree do not offer any way to
figure out which files were changed.

This poses problems for EGit, which may need to refresh parts of the
Eclipse workspace when JGit has done java.io file operations.

Provide the foundations for better file change tracking: the working
tree is modified exclusively in DirCacheCheckout. Make it emit a new
type of RepositoryEvent that lists all files that were modified or
deleted, even if the checkout failed halfway through. We update the
'updated' and 'removed' lists determined up-front in case of file
system problems to reflect the actual state of changes made.

EGit thus can register a listener for these events and then knows
exactly which parts of the Eclipse workspace may need to be refreshed.

Two commands manage checking out individual DirCacheEntries themselves:
checkout specific paths, and applying a stash with untracked files.
Make those two also emit such a new WorkingTreeModifiedEvent.

Furthermore, merges may modify files, and clean, rm, and stash create
may delete files.

CQ: 13969
Bug: 500106
Change-Id: I7a100aee315791fa1201f43bbad61fbae60b35cb
Signed-off-by: Thomas Wolf <thomas.wolf@paranor.ch>

Since the introduction of generic type parameter inference in Java 7,
it's not necessary to explicitly specify the type of generic parameters.

Enable the warning in Eclipse, and fix all occurrences.

Change-Id: I9158caf1beca5e4980b6240ac401f3868520aad0
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

This prevents the warning:

  Potential heap pollution via varargs parameter

The method doesn't do any casting of types that would cause the heap
pollution, so it should be safe to add @SafeVarArgs.

See [1] for information about this warning.

[1] http://stackoverflow.com/a/12462259/381622

Change-Id: Ic6d252915ea44b4f1c385afecb98906cd2c54382
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

A later patch will make use of this class in a org.eclipse.jgit.lib
test.

Change-Id: I2b268e6a5dbf12174201f45259f9f007686708d2
Signed-off-by: Jonathan Nieder <jrn@google.com>