code: public void outputAnnotationIndex(PrintWriter writer) {
          for (String ann : annotationIndex.keySet()) {
              writer.print(ann);
              writer.print(": ");
              Set<String> classes = annotationIndex.get(ann);
              Iterator<String> it = classes.iterator();
              while (it.hasNext()) {
                  writer.print(it.next());
                  if (it.hasNext())
                      writer.print(", ");
              }
              writer.println();
          }
      }
docs: Prints out annotationIndex
  
  @param writer