@Override
  protected void appendFields(StringBuilder buff) {
    super.appendFields(buff);
    buff.append("; bucketId=").append(bucketIds);
    buff.append("; recipient=").append(getRecipient());
  }
Sends a PartitionedRegion message to fetch all the entries for a bucketId

@param recipient the member that the fetch keys message is sent to
@param r the PartitionedRegion that contains the bucket
@param bucketIds the identity of the buckets that contain the entries to be returned
@param regex the regular expression to be evaluated for selecting keys
@return the processor used to read the returned entries
@throws ForceReattemptException if the peer is no longer available
geode-core/src/main/java/org/apache/geode/internal/cache/partitioned/FetchBulkEntriesMessage.java