public Set getKeys() {
    Set keys = new HashSet(getSize());
    for (final RemoveAllEntryData removeAllPRDatum : removeAllPRData) {
      if (removeAllPRDatum != null) {
        keys.add(removeAllPRDatum.getKey());
      }
    }
    return keys;
  }
Empty constructor to satisfy {@link DataSerializer} requirements
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/RemoveAllPRMessage.java