@Override
  public void addCqListener(CqListener aListener) {
    if (true) {
      throw new IllegalStateException(
          "Not yet supported.");
    }
  }
Adds a cq listener to the end of the list of cq listeners on this CqQuery.

@param aListener the user defined cq listener to add to the CqQuery.
@throws IllegalArgumentException if <code>aListener</code> is null
geode-cq/src/main/java/org/apache/geode/cache/query/cq/internal/CqAttributesMutatorImpl.java