code: private List<JSONObject> findAllMembers(@Nullable String loadBalancerId) throws CloudException, InternalException {
          NovaMethod method = new NovaMethod(getProvider());
          JSONObject result = method.getNetworks(getMembersResource(), null, false, "?tenant_id="+getContext().getAccountNumber());
          List<JSONObject> members = new ArrayList<JSONObject>();
          if( result != null && result.has("members") ) {
              try {
                  JSONArray list = result.getJSONArray("members");
                  for( int i = 0; i < list.length(); i++ ) {
                      JSONObject member = list.getJSONObject(i);
                      if( (loadBalancerId != null && loadBalancerId.equals(member.optString("pool_id")) )
                          || loadBalancerId == null) {
                          members.add(member);
                      }
                  }
              }
              catch( JSONException e ) {
                  logger.error("Unable to understand listMembers response: " + e.getMessage());
                  throw new CloudException(e);
              }
          }
          return members;
      }
docs: Find all members
  @param loadBalancerId optional filter
  @return
  @throws CloudException
  @throws InternalException