AES/ECB/PKCS5Padding

AESUtil.java

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;

/**
 * @author yinheli
 */
public class AESUtil {

    private static final String ALGORITHM = "AES";
    private static final String ALGORITHM_STR = "AES/ECB/PKCS5Padding";

    private SecretKeySpec key;

    public AESUtil(String hexKey) {
        key = new SecretKeySpec(hex2byte(hexKey), ALGORITHM);
    }

    public String encryptData(String data) throws Exception {
        Cipher cipher = Cipher.getInstance(ALGORITHM_STR);
        cipher.init(Cipher.ENCRYPT_MODE, key);
        return new BASE64Encoder().encode(cipher.doFinal(data.getBytes()));
    }

    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)));
    }

    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 {
        AESUtil util = new AESUtil("31323334353637383930313233343539");
        System.out.println("cardNo:"+util.encryptData("4205190000000001"));
        System.out.println("exp:"+util.encryptData("201501"));
        System.out.println("csc:"+util.encryptData("123"));
    }
}