/**
     * 位元組轉FileInputStream
     *
     * @param bytes
     * @return
     */
    public FileInputStream byteToFile(byte[] bytes, String fileName) {
        File file = new File(fileName);
        FileInputStream fileInputStream = null;
        try {
            OutputStream output = new FileOutputStream(file);
            BufferedOutputStream bufferedOutput = new BufferedOutputStream(output);
            bufferedOutput.write(bytes);
            fileInputStream = new FileInputStream(file);
            file.deleteOnExit();
            return fileInputStream;
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return fileInputStream;
    }
 

2018/08/30

注：從伺服器下載檔案，獲得byte[]，要上傳到另一個伺服器上，在位元組轉FileInputStream過程中，檔案被寫在了tomcat某個目錄下，呼叫file.deleteOnExit()並沒有把檔案刪除，可能是bufferedOutput.write(byte[] b)在寫操作時，又生成了檔案