#coding=utf-8

 import os,sys

 reload(sys)

 sys.setdefaultencoding("utf-8")

 def scan_files_sub_dir(directory,prefix=None,postfix=None):

     files_list=[]

     for root, sub_dirs, files in os.walk(directory):

         for special_file in files:

             if postfix:

                 if special_file.endswith(postfix):

                     files_list.append(os.path.join(root,special_file))

             elif prefix:

                 if special_file.startswith(prefix):

                     files_list.append(os.path.join(root,special_file))

             else:

                 files_list.append(os.path.join(root,special_file))

     return files_list

 files  = scan_files_sub_dir(".",None,".txt")

 print files

 def scan_files(directory,prefix=None,postfix=None):

     files_list=[]

     for file in os.listdir(directory):

         if postfix:

                 if file.endswith(postfix):

                     files_list.append(file)

         elif prefix:

             if file.startswith(prefix):

                 files_list.append(file)

         else:

             files_list.append(file)

     return files_list

 files  = scan_files(".",None,".txt")

 print files

import os

def get_file_lists(init_dir,postfix=None):

    file_lists = []

    if not os.path.exists(init_dir):

        print('%s not exist'%init_dir)

        return file_lists

    if not os.path.isdir(init_dir):

        print('%s not dir'%init_dir)

        return file_lists

    for file in os.listdir(init_dir):

        path = "%s\%s"%(init_dir,file)

        if postfix and not file.endswith(postfix) and os.path.isfile(path):

            continue

        if not os.path.isdir(path):

            file_lists.append(path)

        if os.path.isdir(path):

            file_lists.extend(get_file_lists(path,postfix))

    return file_lists

file_lists = get_file_lists(r'D:\Program Files\Java','java')

file_writer = open('list.txt','w',encoding='utf-8')

for file in file_lists:

    file_writer.write("%s\n"%file)

file_writer.close()