lucene为pdf文件建立索引并搜索的有关问题

public class testIndexer {    private IndexWriter writer;    public testIndexer(String indexDir) throws CorruptIndexException, LockObtainFailedException, IOException    {        Directory dir = FSDirectory.open(new File(indexDir));        writer = new IndexWriter(dir,new IKAnalyzer(),true,IndexWriter.MaxFieldLength.UNLIMITED);    }    public void close() throws CorruptIndexException, IOException    {        writer.close();    }    public void indexPDFile(String filename) throws Exception    {        File file = new File(filename);        String content = PdfExtractor.getText(file);        Document doc = new Document();        doc.add(new Field("content",content,Field.Store.YES,Field.Index.ANALYZED));        writer.addDocument(doc);    }        public static void main(String args[])    {        String path="k:/aaaa";        String pdfile="k:/kaks.pdf";        try {            testIndexer indx = new testIndexer(path);            indx.indexPDFile(pdfile);         }catch (Exception e) {                // TODO Auto-generated catch block                e.printStackTrace();            }    }}

public class testSearch {    public static void main(String args[]) throws IOException, ParseException    {        String indexDir = "K:/aaaa";        String q = "分子";        search(indexDir,q);    }    public static void search(String indexDir,String q) throws IOException,ParseException    {        Directory dir = FSDirectory.open(new File(indexDir));        IndexSearcher is = new IndexSearcher(dir,true);        QueryParser parser = new QueryParser(Version.LUCENE_35,"content",new IKAnalyzer());        Query query = parser.parse(q);                TopDocs hits = is.search(query, 10);        for(ScoreDoc scoreDoc:hits.scoreDocs)        {            Document doc = is.doc(scoreDoc.doc);            System.out.println(doc.get("content"));        }        is.close();    }}