code: public void removeTopic(String topic)
      {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "removeTopic", topic);
  
          SelectionCriteria[] tmp = selectionCriteriaList;
  
          // Loop through the selectionCriteriaList
          for (int i = 0; i < selectionCriteriaList.length; ++i)
          {
              if ((selectionCriteriaList[i].getDiscriminator() == null && topic == null) ||
                  (topic != null && selectionCriteriaList[i].getDiscriminator().equals(topic)))
              {
                  // If there was only one criteria and we have removed it then
                  // nullify lists
                  if (selectionCriteriaList.length == 1)
                  {
                      selectionCriteriaList = null;
                      topics = null;
                  }
                  else
                  {
                      // The criteria match, so resize the array without this
                      // criteria in it.
                      tmp = new SelectionCriteria[selectionCriteriaList.length - 1];
                      System.arraycopy(selectionCriteriaList, 0, tmp, 0, i);
                      System.arraycopy(selectionCriteriaList, i + 1, tmp, i, selectionCriteriaList.length - i - 1);
  
                      selectionCriteriaList = tmp;
  
                      // And copy into the topics array so that they always match
                      this.topics = new String[selectionCriteriaList.length];
                      for (int t = 0; t < selectionCriteriaList.length; t++)
                      {
                          topics[t] = (selectionCriteriaList[t] == null) ? null : selectionCriteriaList[t].getDiscriminator();
                      }
                  }
  
                  break;
              }
          }
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "removeTopic");
      }
docs: Remove a topic from the array of topics
  
  @param topic The topic to remove