小编Chr*_*Han的帖子

我试图使密钥库帮助我生成用于AES加密的密钥，并使用它来加密我输入的纯文本。所以这是我的代码。我在另一个活动的onCreate（）方法中仅调用一次createKey（）方法，然后使用相同的keyAlias和相同的纯文本多次调用printCipherText（）方法。奇怪的是：每次我调用printCipherText（）方法时，都会得到不同的结果。我使用相同的密钥别名和相同的明文，但是为什么每次都得到不同的密文？

public class KeyCreatorClass {

    KeyStore keyStore;
    KeyGenerator keyGenerator;
    Cipher cipher;

    public void createKey(String keyAlias) { //I call this method only once in the onCreate() method of another activity, with keyAlias "A"
        try {
            keyStore = KeyStore.getInstance("AndroidKeyStore");
            keyGenerator = KeyGenerator.getInstance(KeyProperties.KEY_ALGORITHM_AES, "AndroidKeyStore");
            cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
            keyStore.load(null);
            keyGenerator.init(
                    new KeyGenParameterSpec.Builder(keyAlias, KeyProperties.PURPOSE_ENCRYPT | KeyProperties.PURPOSE_DECRYPT)
                        .setBlockModes(KeyProperties.BLOCK_MODE_CBC)
                        .setUserAuthenticationRequired(false)
                        .setEncryptionPaddings(KeyProperties.ENCRYPTION_PADDING_PKCS7)
                        .setRandomizedEncryptionRequired(false)
                        .build());
            keyGenerator.generateKey();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public String printCipherText(String keyAlias, String plainText){ //I call this method many times with the same …