String pathname = "E:\\workspace\\stanfordner\\sample.txt";
File filename = new File(pathname); // 要读取以上路径的input。txt文件
String query_id = filename.getName().substring(0,filename.getName().lastIndexOf(".")); Java 返回文件名字，不加后缀,布布扣,bubuko.com
原文：http://blog.csdn.net/nickyzhi/article/details/37697101