删除一个目录下的全部文件
File file_folder = new File("xiaowangzi"+"\\");
File[] file_list = file_folder.listFiles();
for(int i=0; i<file_list.lenth; i++){
if(file_list[i].isfile())
file_list[i].delete();
}
读写文件
File file = new File("xiaowangzi"+"xiaowang.txt");
BufferedWriter bw = new BufferedWriter(new FileWriter(file));
bw.write("what you want to write");
bw.close();