code: public synchronized void syncBuildPath(IVdmProject project)
  			throws CoreException
  	{
  		List<IVdmSourceUnit> syncedVdmSourceUnits = project.getSpecFiles();
  
  		List<IFile> removedFiles = new Vector<IFile>();
  		IProject p = (IProject) project.getAdapter(IProject.class);
  
  		for (IFile file : vdmSourceUnits.keySet())
  		{
  			if (file.getProject().equals(p)
  					&& !syncedVdmSourceUnits.contains(vdmSourceUnits.get(file)))
  			{
  				removedFiles.add(file);
  				System.out.println("Found an existing file removed from build path: "
  						+ file);
  			}
  		}
  
  		// remove the old files
  		for (IFile iFile : removedFiles)
  		{
  			remove(iFile);
  		}
  	}
docs: Sync existing IVdmSource files with the build path of the project. This is used when the build path changed and
  the project should be updated. This method removed old IVdmSource files which no longer is withing the build
  path.
  
  @param project
  @throws CoreException