Java實現非對稱算法AES

/**
 * Created by Because of you on 2020/1/7.
 */
public class AES {

    /**
     * 密鑰算法
     */
    private static final String ALGORITHM = "AES";
    /**
     * 加解密算法/工作模式/填充方式
     */
    private static final String ALGORITHM_STR = "AES/ECB/PKCS5Padding";

    /**
     * SecretKeySpec類是KeySpec接口的實現類,用於構建祕密密鑰規範
     */
    private SecretKeySpec key;

    public AES(String hexKey) {
        key = new SecretKeySpec(hexKey.getBytes(), ALGORITHM);
    }

    /**
     * AES加密
     * @param data
     * @return
     * @throws Exception
     */
    public  String encryptData(String data) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM_STR); // 創建密碼器
        cipher.init(Cipher.ENCRYPT_MODE, key);// 初始化
        return new BASE64Encoder().encode(cipher.doFinal(data.getBytes("UTF-8")));
    }

    /**
     * AES解密
     * @param base64Data
     * @return
     * @throws Exception
     */
    public String decryptData(String base64Data) throws Exception{
        Cipher cipher = Cipher.getInstance(ALGORITHM_STR);
        cipher.init(Cipher.DECRYPT_MODE, key);
        return new String(cipher.doFinal(new BASE64Decoder().decodeBuffer(base64Data)));
    }

    /**
     * hex字符串 轉 byte數組
     * @param s
     * @return
     */
    private static byte[] hex2byte(String s) {
        if (s.length() % 2 == 0) {
            return hex2byte (s.getBytes(), 0, s.length() >> 1);
        } else {
            return hex2byte("0"+s);
        }
    }

    private static byte[] hex2byte (byte[] b, int offset, int len) {
        byte[] d = new byte[len];
        for (int i=0; i<len*2; i++) {
            int shift = i%2 == 1 ? 0 : 4;
            d[i>>1] |= Character.digit((char) b[offset+i], 16) << shift;
        }
        return d;
    }

    public static void main(String[] args) throws Exception {
        AES util = new AES("abcdefghijklmnop"); // 密鑰
        System.out.println("cardNo:"+util.encryptData("1234")); // 加密
        System.out.println("exp:"+util.decryptData("34+Jzs4KkwaCQWVyyAgwLA==")); // 解密
    }
}