@Override
  public void stop(CoprocessorEnvironment env) throws IOException {
    stopConnectorServer();
  }
workaround for HBASE-11146 master and regionserver are in 1 JVM in standalone mode only 1 JMX
instance is allowed, otherwise there is port conflict even if we only load regionserver
coprocessor on master
hbase-server/src/main/java/org/apache/hadoop/hbase/JMXListener.java