code: public static boolean copy(InputStream in, File dstFile) {
          if (in == null || dstFile == null) {
              return false;
          }
  
          OutputStream out = null;
          boolean result = false;
  
          try {
              createFolder(dstFile.getParentFile());
  
              out = new FileOutputStream(dstFile);
  
              byte[] buffer = new byte[10240];
              int read;
              while ((read = in.read(buffer)) != -1) {
                  out.write(buffer, 0, read);
              }
              buffer = null;
              result = true;
          } catch (IOException e) {
              Log.e(TAG, "", e);
          } finally {
              if (out != null) {
                  try {
                      out.flush();
                      out.close();
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              out = null;
          }
          return result;
      }
docs: 拷贝文件, 不关闭流
  
  @param in
  @param dstFile
  @return