private void initializeCompilationErrorIndexes() {
localCompilationErrorsIndex = new CompilationErrorsIndexImpl();
libraryCompilationErrorsIndex = libraryGroup != null
? libraryGroup.getCompilationErrorsIndex() : new CompilationErrorsIndexImpl();
globalCompilationErrorsIndex = new CombinedCompilationErrorsIndex(localCompilationErrorsIndex,
libraryCompilationErrorsIndex);
}