我有兩個類,一個是主類,另一個是AES的實現(xiàn).

但是,在我的AES類中,我有一種解密字符串的方法,但是每當(dāng)我運(yùn)行它時,它都會產(chǎn)生異常

我的加密方法工作正常,但我的解密方法無法正常工作.

編碼

private Cipher aesCipherForDecryption;
String strDecryptedText = new String();

public String decryptAES(final String ciphertext) {

    try {

        aesCipherForDecryption = Cipher.getInstance("AES/CBC/PKCS5PADDING");
        aesCipherForDecryption.init(Cipher.DECRYPT_MODE, secretKey, new IvParameterSpec(iV));
        byte[] byteDecryptedText = aesCipherForDecryption.doFinal(byteCipherText);
        strDecryptedText = new String(byteDecryptedText);

    } catch (IllegalBlockSizeException e) {
        System.out.print("IllegalBlockSizeException "  e);
    } catch (BadPaddingException e) {
        System.out.print("BadPaddingException " e);
    } catch (NoSuchAlgorithmException e) {
        System.out.print("NoSuchAlgorithmException "  e);
    } catch (NoSuchPaddingException e) {
        System.out.print("NoSuchPaddingException " e);
    } catch (InvalidKeyException e) {
        System.out.print("InvalidKeyException " e);
    } catch (InvalidAlgorithmParameterException e) {
        System.out.print("InvalidAlgorithmParameterException " e);
    }

    System.out.println("\nDecrypted Text message is "   strDecryptedText);
    return strDecryptedText;
}

該方法輸出的錯誤是

InvalidKeyException java.security.InvalidKeyException: No installed provider supports this key: (null)

更新#1：

所以我更新了以下代碼

public String decryptAES(byte[] ciphertext) {
    String strDecryptedText = new String();
        try {
            byte[] byteDecryptedText = aesCipherForDecryption.doFinal(ciphertext);

            strDecryptedText = new String(byteDecryptedText);

        } catch (IllegalBlockSizeException e) {
            System.out.print("IllegalBlockSizeException " e);
            e.printStackTrace();
        } catch (BadPaddingException e) {
            System.out.print("BadPaddingException " e);
            e.printStackTrace();
        }

    System.out.println("\nDecrypted Text message is "   strDecryptedText);
    return strDecryptedText;
}    

在主班我有這條線

byte [] byteciphertext = ciphertext.getBytes();

只是將字符串轉(zhuǎn)換為字節(jié)

這是正確的嗎？我還有

IllegalBlockSizeException javax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipherjavax.crypto.IllegalBlockSizeException: Input length must be multiple of 16 when decrypting with padded cipher

有人可以幫我解決這個問題嗎？

謝謝.

解決方法:

secretKey顯然為null.

其他問題：

>您沒有使用輸入?yún)?shù)cipherText.
>輸入?yún)?shù)cipherText應(yīng)該是byte [],而不是字符串：密文是二進(jìn)制的,并且String不是二進(jìn)制數(shù)據(jù)的容器.
>結(jié)果字符串strDecryptedText應(yīng)該是局部變量,而不是成員變量.