code: @Override
      protected List<URL> getSources() {
  
          final List<Filter<File>> sourceExcludes = schemaSourceExcludeFilters == null
                  ? STANDARD_SOURCE_EXCLUDE_FILTERS
                  : schemaSourceExcludeFilters;
          Filters.initialize(getLog(), sourceExcludes);
  
          final List<String> defaultSources = getProject().getCompileSourceRoots();
  
          // All Done.
          return FileSystemUtilities.filterFiles(
                  getProject().getBasedir(),
                  (sources == null) ? defaultSources : sources,
                  defaultSources,
                  getLog(),
                  "sources",
                  sourceExcludes);
      }
docs: {@inheritDoc}