code: @Override
      public void updateClassFileTimestamp( File classFile )
      {
          if ( stamps == null )
          {
              stamps = analysis.stamps();
          }
          Stamp existingStamp = stamps.product( classFile );
          if ( existingStamp != null && existingStamp instanceof LastModified )
          {
              Stamp newStamp = new LastModified( classFile.lastModified() );
              stamps = stamps.markProduct( classFile, newStamp );
          }
      }
docs: {@inheritDoc}