private static boolean hasMultipleColumnFamilies(Collection<Pair<byte[], String>> familyPaths) {
    boolean multipleFamilies = false;
    byte[] family = null;
    for (Pair<byte[], String> pair : familyPaths) {
      byte[] fam = pair.getFirst();
      if (family == null) {
        family = fam;
      } else if (!Bytes.equals(family, fam)) {
        multipleFamilies = true;
        break;
      }
    }
    return multipleFamilies;
  }
Determines whether multiple column families are present Precondition: familyPaths is not null
@param familyPaths List of (column family, hfilePath)
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java