code: public AbstractBuilder getAnnotationTypeBuilder(
          AnnotationTypeDoc annotationType,
          Type prevType, Type nextType)
              throws Exception {
          return AnnotationTypeBuilder.getInstance(context, annotationType,
              writerFactory.getAnnotationTypeWriter(annotationType, prevType, nextType));
      }
docs: Return the builder for the annotation type.
  
  @param annotationType the annotation type being documented.
  @param prevType the previous type that was documented.
  @param nextType the next type being documented.
  @return the writer for the annotation type.  Return null if this
  writer is not supported by the doclet.