code: @Nonnull
  	private static Package createPackage(@Nonnull final String packageName) {
  		Check.notNull(packageName, "packageName");
  		return packageName.isEmpty() ? Package.UNDEFINED : new Package(packageName);
  	}
docs: Creates a new instance of {@code Package} when the given name is not empty other wise it returns
  {@link Package#UNDEFINED}.
  
  @param packageName
  package name
  @return instance of {@code Package} and never null