public void addSourcesToClasspath(@NotNull VirtualFile root) {
    assert root.isDirectory();
    ((CoreJavaFileManager)myFileManager).addToClasspath(root);
    ((CorePackageIndex)myPackageIndex).addToClasspath(root);
    ((MockFileIndexFacade)myFileIndexFacade).addLibraryRoot(root);
  }
public void addSourcesToClasspath(@NotNull VirtualFile root)