public static String getLoadedCoprocessors() {
    return CoprocessorHost.getLoadedCoprocessors().toString();
  }
The set of loaded coprocessors is stored in a static set. Since it's statically allocated, it
does not require that HMaster's cpHost be initialized prior to accessing it.
@return a String representation of the set of names of the loaded coprocessors.
hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java