在通過文件上傳之后，運行java程序，突然發現這么一個錯誤：java.lang.ClassFormatError: Unknown constant tag 0 in class file，通過網上查找，很多人認為是要重新編譯，可是按照這個方法重新編譯之后還是得到同樣的結果！百思不得其解！
最后通過：
Maybe it's yet to appear, but I found (and replied) that it was due to an SCP file transfer (of a binary 'class' file) in ascii mode from Windows to Unix.
(1) I did a hex dump of the files on their respective computers, and the two copies of the same class file differed.
(2) I did the transfer again in binary mode and the class file now works. (and, the two files no longer differ.)
獲得答案，就是在上傳類文件的時候使用了ASCII的模式，而java編譯之后的類文件是需要采用binary模式的，改變上傳文件的模式之后問題獲得了解決！