1、对文件进行检索，文件名如果不含汉字，则必须输入文件名+类型，方可检索到

2、对文件类容进行检索，.txt文件可检索到内容，其它则不可以

请问这是为什么？

public class Demo {

public static void createIndex(Directory dir,Analyzer analyzer) throws CorruptIndexException, LockObtainFailedException, IOException{
IndexWriter writer=new IndexWriter(dir,analyzer,true,IndexWriter.MaxFieldLength.UNLIMITED);
File file=new File("E:\\1231313.txt");

Document doc=new Document();
doc.add(new Field("name",file.getName(),Field.Store.YES,Field.Index.ANALYZED));
doc.add(new Field("content",new FileReader(file)));
writer.addDocument(doc);

writer.close();
}

public static void search(Directory dir,Analyzer analyzer) throws CorruptIndexException, IOException, ParseException{
Searcher searcher=new IndexSearcher(dir);
Query query=new QueryParser("name",analyzer).parse("1231313");

ScoreDoc[] docs=searcher.search(query, searcher.maxDoc()).scoreDocs;
System.out.println(docs.length);

Document doc;
for(int i=0;i<docs.length;i++){
doc=searcher.doc(docs[i].doc);
System.out.println(doc.get("name"));
}

query=new QueryParser("content",analyzer).parse("范德 飞洒");

docs=searcher.search(query, searcher.maxDoc()).scoreDocs;
System.out.println(docs.length);

for(int i=0;i<docs.length;i++){
doc=searcher.doc(docs[i].doc);
System.out.println(doc.get("name"));
}
}

public static void main(String[] args) throws IOException, ParseException {
Analyzer analyzer=new StandardAnalyzer();
FSDirectory dir=FSDirectory.getDirectory(new File("e://iii"));
createIndex(dir, analyzer);
search(dir, analyzer);
dir.close();
}

}