eclipse: change the package of a class via ast

Question

How can I programmatically change the package of a class in Eclipse. In a way to have the same result as when drag-dropping the class into another package. I assume it must be done using AST, but can't find a proper tutorial describing it.

Answer 1

Ok, I will answer to my own question (like a Sir:)). I had to debug into Eclipse and here is how it works:

CompositeChange composite = new DynamicValidationStateChange(RefactoringCoreMessages.ReorgPolicy_move);
MoveCuUpdateCreator creator = new MoveCuUpdateCreator(new ICompilationUnit[] {compUnit}, (IPackageFragment) newContainer);
TextChangeManager fChangeManager = creator.createChangeManager(new SubProgressMonitor(pm, 1), new RefactoringStatus());
composite.merge(new CompositeChange(RefactoringCoreMessages.MoveRefactoring_reorganize_elements, fChangeManager.getAllChanges()));
Change change = new MoveCompilationUnitChange(compUnit, (IPackageFragment) newContainer);
if (change instanceof CompositeChange) {
    composite.merge(((CompositeChange) change));
} else {
    composite.add(change);
}
composite.perform(pm);