public static void indexFileUpdate(Photo[] list, IndexWriter diskWriter,String indexDir,String uid) throws CorruptIndexException, IOException {
diskWriter.deleteDocuments(new Term("uid",uid));//这里删除id=uid的文档，还会留在”回收站“。x.del
diskWriter.optimize();//清空回收站

Document doc = new Document();

doc.add(new Field("uid",String.valueOf(list[0].getUid()), Field.Store.YES, Field.Index.TOKENIZED));
doc.add(new Field("name",list[0].getName(),Field.Store.YES,Field.Index.TOKENIZED));
doc.add(new Field("card_id", list[0].getCard_id(), Field.Store.YES,Field.Index.TOKENIZED));
doc.add(new Field("url",list[0].getUrl(),Field.Store.YES,Field.Index.TOKENIZED));

diskWriter.addDocument(doc);
diskWriter.close();
}
更新索引我是先删除再增量的，但是这中间有30秒的时间，太慢了，有什么优化的方法吗