code: private String generateIncrementedId (String componentId) {
          Integer serialNum = (Integer) context.getAttributes().get(componentId);
          if (null == serialNum) {
              serialNum = 1;
          } else {
              serialNum = serialNum.intValue() + 1;
          }
          context.getAttributes().put(componentId, serialNum);
          componentId = componentId + UNIQUE_ID_PREFIX + serialNum.intValue();
          return componentId;
      }
docs: /*
  Appends a counter to the passed in <code>id</code> and stores the
  <code>id</code> and counter information in request scope.
  
  @return String <code>id</code> with a counter appended to it.