这似乎是一个简单的错误. 您替换了

This seems to be a simple mistake. You replaced

String abc = Base64.getDecoder().decode(encrypt);

使用

byte[] encodeBytes = null;
encodeBytes = Base64.encode(my_encrypted_string.getBytes(),Base64.DEFAULT);

如果我没看错的话.尝试用 decode .

if I read this correctly. Try to replace that with decode instead.

由于密文是对Base64进行两次编码而不是在尝试对其进行解密之前进行解码的，因此解密失败并显示您向我们显示的错误.

As the ciphertext is Base64 encoded twice instead of decoded before attempting to decrypt it, decryption fails with the error you showed us.