private SourceFolder addSourceFolder(final String url, boolean isTestSource, String packagePrefix) {
    final JavaSourceRootType rootType = isTestSource ? JavaSourceRootType.TEST_SOURCE : JavaSourceRootType.SOURCE;
    JavaSourceRootProperties properties = JpsJavaExtensionService.getInstance().createSourceRootProperties(packagePrefix);
    return addSourceFolder(url, rootType, properties);
  }
private SourceFolder addSourceFolder(final String url, boolean isTestSource, String packagePrefix)