lucene:no segments* file found in org.apache.lucene.store.FSDirectory@异常

目的：我想把内存中的索引合并到磁盘文件中。
异常：org.apache.lucene.index.IndexNotFoundException: no segments* file found in org.apache.lucene.store.RAMDirectory@1e94b0ca lockFactory=org.apache.lucene.store.SingleInstanceLockFactory@33e2ad75: files: [_0.fdx, _0.fdt] at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:741) at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:630) at org.apache.lucene.index.SegmentInfos.read(SegmentInfos.java:343) at org.apache.lucene.index.IndexWriter.addIndexes(IndexWriter.java:2333) at org.apache.lucene.demo.IKAnalyzerT.createIndex(IKAnalyzerT.java:45) at org.apache.lucene.demo.IKAnalyzerT.main(IKAnalyzerT.java:58)

意思是：我在把内存索引合并到磁盘的时候 内存中没有索引文件。

我的解决方案参考： 在索引库没有建立并且没有索引文件的时候首先要commit一下让他建立一个

  

public class X {
    public static void main(String[] args) throws Exception{
        Analyzer a = new StandardAnalyzer(Version.LUCENE_CURRENT);
        IndexDeletionPolicy commitDeletionPolicy = new  SolrDeletionPolicy();
        FSDirectory directory = FSDirectory.open(new File("c:\\"));

        IndexWriterConfig config = new
        IndexWriterConfig(Version.LUCENE_CURRENT,a);
        config.setOpenMode(OpenMode.CREATE_OR_APPEND);
        config.setIndexDeletionPolicy(commitDeletionPolicy);
        IndexWriter writer = new IndexWriter(directory, config);

        // -----------------
        // 在索引库没有建立并且没有索引文件的时候首先要commit一下让他建立一个
        // 索引库的版本信息
        //writer.commit();
        // -----------------

        //如果第一次没有commit就打开一个索引读取器的话就会报异常
        IndexReader reader = IndexReader.open(directory);
        System.out.println(reader);
        //Exception in thread "main" org.apache.lucene.index.IndexNotFoundException: no segments* file found in org.apache.lucene.store.SimpleFSDirectory@C:\ lockFactory=org.apache.lucene.store.NativeFSLockFactory@15a8767: files: [bootmgr, BOOTSECT.BAK, pagefile.sys, write.lock]
        // at
        // org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:711)
        // at
        // org.apache.lucene.index.DirectoryReader.open(DirectoryReader.java:75)
        // at org.apache.lucene.index.IndexReader.open(IndexReader.java:428)
        // at org.apache.lucene.index.IndexReader.open(IndexReader.java:274)
        // at com.zyb.solrQuery.X.main(X.java:39)
    }
}