/**
 * AES 算法
 * <p/>
 * 算法采用加密模式：CBC；數(shù)據(jù)塊：128；填充：PKCS5Padding
 * <p/>
 * key 與向量字符串的長(zhǎng)度為 16 位
 *
 * @author Deniro Li (lisq037@163.com)
 *     2018/3/17
 */
public class AES {
  /**
   * 算法名稱
   */
  public static final String NAME = "AES";
  /**
   * 加密模式：CBC；數(shù)據(jù)塊：128；填充：PKCS5Padding
   */
  public final String MODE = "AES/CBC/PKCS5Padding";
  /**
   * KEY 與 向量字符串的長(zhǎng)度
   */
  public static final int LENGTH = 16;
  /**
   * 加密用的 KEY
   */
  private String key;
  /**
   * 向量，用于增加加密強(qiáng)度
   */
  private String ivParameter;
  /**
   * @param key     加密用的 KEY
   * @param ivParameter 偏移量
   */
  public AES(String key, String ivParameter) {
    if (key == null || key.length() != LENGTH) {
      throw new AESException("KEY 不存在，或者長(zhǎng)度不為 " + LENGTH);
    }
    if (ivParameter == null || ivParameter.length() != LENGTH) {
      throw new AESException("ivParameter 不存在，或者長(zhǎng)度不為 " + LENGTH);
    }
    this.key = key;
    this.ivParameter = ivParameter;
  }
  /**
   * 加密
   *
   * @param s 要加密的字符串
   * @return 加密后的字符串
   */
  public String encode(String s) {
    String result;
    try {
      Cipher cipher = Cipher.getInstance(MODE);
      IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());
      cipher.init(ENCRYPT_MODE, new SecretKeySpec(key.getBytes(), NAME), iv);
      byte[] bytes = cipher.doFinal(s.getBytes(ENCODING));
      result = new BASE64Encoder().encode(bytes);
    } catch (Exception e) {
      throw new AESException("加密", e);
    }
    return result;
  }
  /**
   * 解密
   *
   * @param s 待解密的字符串
   * @return 解密后的字符串
   */
  public String decode(String s) {
    try {
      SecretKeySpec keySpec = new SecretKeySpec(key.getBytes("ASCII"), NAME);
      Cipher cipher = Cipher.getInstance(MODE);
      IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());
      cipher.init(Cipher.DECRYPT_MODE, keySpec, iv);
      return new String(cipher.doFinal(new BASE64Decoder().decodeBuffer(s)), ENCODING);
    } catch (Exception e) {
      throw new AESException("解密", e);
    }
  }
}

public class AESTest {
  AES aes;
  @Before
  public void init(){
    aes=new AES("12345abcdef67890","1234567890abcdef");
  }
  @Test
  public void testEncode() throws Exception {
    Assert.assertEquals("jANei3LBvnLCaZ2XddWHZw==", aes.encode("123456"));
  }
  @Test
  public void testDecode() throws Exception {
    Assert.assertEquals("123456", aes.decode("jANei3LBvnLCaZ2XddWHZw=="));
  }
}