public static void main(String[] args) throws Exception {
    // String f="d:"+File.separator+"data"+File.separator+"fword.txt";
          String f="d:"+File.separator+"data";
     File m=new File(f);
     String[] s=m.list(new FilenameFilter(){

        public boolean accept(File dir, String name) {
            int m=name.indexOf(".java");
            int k=name.indexOf(".txt");
            return m!=-1||k!=-1;
        }
        
     });
     for(int i=0;i<s.length;i++){
         System.out.println(s[i]);
     }
    }

}