lucene索引出错 checksum mismatch in segments file

org.apache.lucene.index.CorruptIndexException: checksum mismatch in segments file
at org.apache.lucene.index.SegmentInfos.read(SegmentInfos.java:322)
at org.apache.lucene.index.DirectoryReader$1.doBody(DirectoryReader.java:79)
at org.apache.lucene.index.SegmentInfos$FindSegmentsFile.run(SegmentInfos.java:736)
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:288)
at org.apache.lucene.search.IndexSearcher.<init>(IndexSearcher.java:82)
at com.NewsList.Search.LuceneSearch.getDocsByWords(LuceneSearch.java:95)
at com.NewsList.Search.LuceneSearch.getDocsByWords(LuceneSearch.java:177)
at com.NewsList.Search.LuceneSearch.main(LuceneSearch.java:195)
Exception in thread "main" java.lang.NullPointerException
at com.NewsList.Search.LuceneSearch.getDocsByWords(LuceneSearch.java:133)
at com.NewsList.Search.LuceneSearch.getDocsByWords(LuceneSearch.java:177)
at com.NewsList.Search.LuceneSearch.main(LuceneSearch.java:195)
lucene检索出错，请问怎样修改？？？ Directory dir = null;
try {
dir = FSDirectory.open(new File(indexPath));
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

Analyzer anylyzer=new IKAnalyzer();
IndexSearcher indexsearch =null;

try {
indexsearch = new IndexSearcher(dir);              //出错
} catch (CorruptIndexException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} //QueryParser qparser = new QueryParser(Version.LUCENE_31, "Content", anylyzer);
Query query=null;
try {
query = IKQueryParser.parseMultiField(new String[]{"Title","Content"},word,new BooleanClause.Occur[]{BooleanClause.Occur.SHOULD,BooleanClause.Occur.SHOULD});
//qparser.parse(word);
//IKQueryParser.parseMultiField(new String[]{"Title","Content"}, "卡扎菲",new BooleanClause.Occur[]{BooleanClause.Occur.SHOULD,BooleanClause.Occur.SHOULD});
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}