code: public Collection<AlertChannel> list(long policyId)
      {
          Map<Long,AlertChannel> map = new HashMap<Long,AlertChannel>();
          Collection<AlertChannel> channels = list();
          for(AlertChannel channel : channels)
          {
              List<Long> channelPolicyIds = channel.getLinks().getPolicyIds();
              for(long channelPolicyId : channelPolicyIds)
              {
                  if(channelPolicyId == policyId)
                      map.put(channel.getId(), channel);
              }
          }
          return map.values();
      }
docs: Returns the set of alert channels for the given policy id.
  @param policyId The id of the policy for the alert channels
  @return The set of alert channels