Lucene3.0显示高亮的问题

Question

    public Map<String, Object> displayHtmlHighlight(String queryString, Analyzer analyzer, int fragmentSize, Content con) throws IOException, InvalidTokenOffsetsException, ParseException{
         Map<String, Object> map = new HashMap<>();
         map.put("id", con.getId());
         System.out.println("原始的标题-----------------"+con.getTitle());
        QueryParser qp = new QueryParser(Version.LUCENE_30, "title", analyzer);
        Query query = qp.parse(queryString);
        Highlighter highlighter = new Highlighter(new SimpleHTMLFormatter("<font color='red'>", "</font>"), new QueryScorer(query));
        Fragmenter fragmenter = new SimpleFragmenter(fragmentSize);
        highlighter.setTextFragmenter(fragmenter);
        String title = highlighter.getBestFragment(analyzer, "title", con.getTitle());
        map.put("title", title);
        System.out.println("改动后的标题--------------"+title);
        System.out.println("原始的内容-----------------"+con.getTxt());
        String content = highlighter.getBestFragment(analyzer, "content", con.getTxt());
        System.out.println("--改动后的内容----"+content);
        map.put("content", content);
        System.out.println(map.toString());
        return map;
    }

我的标题：我的滑板鞋时尚，queryString = 我的 ，fragmentSize设置为200
但是： String title = highlighter.getBestFragment(analyzer, "title", con.getTitle());这个报错了，queryString为一个字就正确，两个字以上就报错了，求大神解惑。