protected void checkInvalidInt(int intVal) {
    if (ERRONEOUS_INT_FOR_TO_DELTA == intVal) {
      toDeltaFailure++;
      throw new InvalidDeltaException("Delta could not be extracted. " + this);
    }
  }
**************************************************************************
Below methods are not part of standard Delta implementation but are used for testing purpose.
geode-junit/src/main/java/org/apache/geode/DeltaTestImpl.java