code: public void waitTransformThread() throws SAXException
    {
  
      // This is called to make sure the task is done.
      // It is possible that the thread has been reused -
      // but for a different transformation. ( what if we 
      // recycle the transformer ? Not a problem since this is
      // still in use. )
      Thread transformThread = this.getTransformThread();
  
      if (null != transformThread)
      {
        try
        {
          ThreadControllerWrapper.waitThread(transformThread, this);
  
          if (!this.hasTransformThreadErrorCatcher())
          {
            Exception e = this.getExceptionThrown();
  
            if (null != e)
            {
              e.printStackTrace();
              throw new org.xml.sax.SAXException(e);
            }
          }
  
          this.setTransformThread(null);
        }
        catch (InterruptedException ie){}
      }
    }
docs: Used by SourceTreeHandler to wait until the transform
  completes
  
  @throws SAXException