@Override
  public boolean isInitialized() {
    return initialized.isReady();
  }
Report whether this master has completed with its initialization and is ready. If ready, the
master is also the active master. A standby master is never ready. This method is used for
testing.
@return true if master is ready to go, false if not.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java