lucene3.5更新索引

lucene索引的更新操作其实就是删除索引和添加索引的组合。 
具体代码如下： 
//按term更新文档（lucene并没有提供专门的索引更新方法，我们需要先将相应的document删除，然后再将新的document加入索引） 

public class MyUpdateIndexer{
    public static final String STORE_PATH = "E:/lucene_index";
    public static void updateIndexes(String field , String keyword) throws IOException{
        long startTime = System.currentTimeMillis();
        //首先，我们需要先将相应的document删除
        Directory dir = FSDirectory.open(new File(STORE_PATH));
        IndexReader reader = IndexReader.open(dir,false);
        Term term = new Term(field,keyword);
        reader.deleteDocuments(term);
        reader.close();
        //然后，将新的document加入索引
        Analyzer analyzer = new StandardAnalyzer(Version.LUCENE_35);
        //CREATE - creates a new index or overwrites an existing one
        //APPEND - opens an existing index.
        //CREATE_OR_APPEND - creates a new index if one does not exist,otherwise it opens the index and documents will be appended.
        IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_35,analyzer).setOpenMode(OpenMode.CREATE);
        IndexWriter writer = new IndexWriter(dir, config);
        for(int i = 0;i<100;i++){
            Document doc = new Document();
            doc.add(new Field("title", "lucene title"+i, Field.Store.YES, Field.Index.ANALYZED));
            doc.add(new Field("content", "Apache Lucene(TM) is a high-performance", Field.Store.YES, Field.Index.ANALYZED));
            //纯文本文件索引起来，而不想自己将它们读入字符串创建field
            //这里的file就是该文本文件。该构造函数实际上是读去文件内容，并对其进行索引，但不存储。
            //doc.add(new Field("path", new FileReader(new File("路径"))));
            writer.addDocument(doc);
        }
}
        writer.close();
        long endTime = System.currentTimeMillis();
        System.out.println("total time: " + (endTime - startTime) + " ms");
    }
}