code: @Override
      protected List<URL> getSources() {
  
          final List<Filter<File>> excludePatterns = xjcSourceExcludeFilters == null
                  ? STANDARD_SOURCE_EXCLUDE_FILTERS
                  : xjcSourceExcludeFilters;
          Filters.initialize(getLog(), excludePatterns);
  
          return FileSystemUtilities.filterFiles(
                  getProject().getBasedir(),
                  sources,
                  Arrays.asList(STANDARD_SOURCE_DIRECTORY),
                  getLog(),
                  "sources",
                  excludePatterns);
      }
docs: {@inheritDoc}