服务器获取字节流并保存文件

import java.io.File;  import java.io.FileInputStream;  import java.io.FileNotFoundException;  import java.io.FileOutputStream;  import java.io.IOException;  import java.io.InputStream;  import java.io.OutputStream;      public class Test {        public static void main(String[] args) {          try {              InputStream is = request.getInputStream();                            File filedir = new File("服务器绝对路径文件夹常量");              if (!filedir.exists())              filedir.mkdirs();            File file = new File(filedir, "文件名.后缀名");              OutputStream os = new FileOutputStream(file);                          byte[] byteStr = new byte[1024];              int len = 0;              while ((len = is.read(byteStr)) > 0) {                  os.write(byteStr,0,len);              }              is.close();                            os.flush();              os.close();          } catch (FileNotFoundException e) {              // TODO Auto-generated catch block              e.printStackTrace();          } catch (IOException e) {              // TODO Auto-generated catch block              e.printStackTrace();          }      }  }