code: public static boolean hasInterface(String intf, String cls) {
      String	key;
  
      key = intf + "-" + cls;
      if (m_CheckInterface.containsKey(key))
        return m_CheckInterface.get(key);
  
      try {
        return hasInterface(Class.forName(intf), Class.forName(cls));
      }
      catch (Throwable t) {
        return false;
      }
    }
docs: Checks whether the given class implements the given interface.
  
  @param intf      the interface to look for in the given class
  @param cls       the class to check for the interface
  @return          TRUE if the class contains the interface