public StartTestingClusterOption build() {
      if (dataNodeHosts != null && dataNodeHosts.length != 0) {
        numDataNodes = dataNodeHosts.length;
      }
      return new StartTestingClusterOption(numMasters, numAlwaysStandByMasters, masterClass,
        numRegionServers, rsPorts, rsClass, numDataNodes, dataNodeHosts, numZkServers,
        createRootDir, createWALDir);
    }
Builder pattern for creating an {@link StartTestingClusterOption}.
<p/>
The default values of its fields should be considered public and constant. Changing the default
values may cause other tests fail.
hbase-server/src/test/java/org/apache/hadoop/hbase/StartTestingClusterOption.java