留一个例子，这个算法就是把一段明文经过秘钥，分隔的方法分成几段在进行加密，解密。

例子中秘钥和向量都要求是16字节长度

public class AESTest {  
	
	//加密方式
    public static String KEY_ALGORITHM = "AES";
    //数据填充方式
    String algorithmStr = "AES/CBC/PKCS7Padding";
    //避免重复new生成多个BouncyCastleProvider对象，因为GC回收不了，会造成内存溢出
    //只在第一次调用decrypt()方法时才new 对象
    public static boolean initialized = false;

    /**
     * 
     * @param originalContent
     * @param encryptKey
     * @param ivByte
     * @return
     */
    public static byte[] encrypt(byte[] originalContent, byte[] encryptKey, byte[] ivByte) {
        initialize();
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
            SecretKeySpec skeySpec = new SecretKeySpec(encryptKey, "AES");
            cipher.init(Cipher.ENCRYPT_MODE, skeySpec, new IvParameterSpec(ivByte));
            byte[] encrypted = cipher.doFinal(originalContent);
            return encrypted;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**
     * AES解密
     * 	填充模式AES/CBC/PKCS7Padding
     *	 解密模式128
     * @param content
     *	 目标密文
     * @return
     * @throws Exception 
     * @throws InvalidKeyException 
     * @throws NoSuchProviderException
     */
    public static byte[] decrypt(byte[] content, byte[] aesKey, byte[] ivByte) {
        initialize();
        try {
            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS7Padding");
            Key sKeySpec = new SecretKeySpec(aesKey, "AES");
            cipher.init(Cipher.DECRYPT_MODE, sKeySpec, generateIV(ivByte));// 初始化
            byte[] result = cipher.doFinal(content);
            return result;
        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }

    /**BouncyCastle作为安全提供，防止我们加密解密时候因为jdk内置的不支持改模式运行报错。**/
    public static void initialize() {
        if (initialized)
            return;
        Security.addProvider(new BouncyCastleProvider());
        initialized = true;
    }

    // 生成iv
    public static AlgorithmParameters generateIV(byte[] iv) throws Exception {
        AlgorithmParameters params = AlgorithmParameters.getInstance("AES");
        params.init(new IvParameterSpec(iv));
        return params;
    }
}

需要引入的包是

    <dependency>
		<groupId>org.bouncycastle</groupId>
		<artifactId>bcprov-jdk16</artifactId>
		<version>1.46</version>
	</dependency>

记录一下,以后好找