import javax.crypto.Cipher;

import javax.crypto.spec.IvParameterSpec;

import javax.crypto.spec.SecretKeySpec;

import sun.misc.BASE64Decoder;

import sun.misc.BASE64Encoder;

/**

 * AES 是一种可逆加密算法，对用户的敏感信息加密处理

 * 对原始数据进行AES加密后，在进行Base64编码转化；

 */

public class AESOperator {

    /*

    * 加密用的Key 可以用26个字母和数字组成

    * 此处使用AES-128-CBC加密模式，key需要为16位。

    */

    private String sKey = "0123456789abcdef";

    private String ivParameter = "0123456789abcdef";

    private static AESOperator instance = null;

    private AESOperator() {

    }

    public static AESOperator getInstance() {

        if (instance == null)

            instance = new AESOperator();

        return instance;

    }

    // 加密

    public String encrypt(String sSrc) throws Exception {

        Cipher cipher = Cipher.getInstance("AES / CBC / PKCS5Padding");

        byte[] raw = sKey.getBytes();

        SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");

        IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());//使用CBC模式，需要一个向量iv，可增加加密算法的强度

        cipher.init(Cipher.ENCRYPT_MODE, skeySpec, iv);

        byte[] encrypted = cipher.doFinal(sSrc.getBytes("utf-8"));

        return new BASE64Encoder().encode(encrypted);//此处使用BASE64做转码。

    }

    // 解密

    public String decrypt(String sSrc) throws Exception {

        try {

            byte[] raw = sKey.getBytes("ASCII");

            SecretKeySpec skeySpec = new SecretKeySpec(raw, "AES");

            Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");

            IvParameterSpec iv = new IvParameterSpec(ivParameter.getBytes());

            cipher.init(Cipher.DECRYPT_MODE, skeySpec, iv);

            byte[] encrypted1 = new BASE64Decoder().decodeBuffer(sSrc);//先用base64解密

            byte[] original = cipher.doFinal(encrypted1);

            String originalString = new String(original, "utf-8");

            return originalString;

        } catch (Exception ex) {

            return null;

        }

    }

    public static void main(String[] args) throws Exception {

// 需要加密的字串

        String cSrc = "我来自www.wenhq.com";

        System.out.println(cSrc);

// 加密

        long lStart = System.currentTimeMillis();

        String enString = AESOperator.getInstance().encrypt(cSrc);

        System.out.println("加密后的字串是：" + enString);

        long lUseTime = System.currentTimeMillis() - lStart;

        System.out.println("加密耗时：" + lUseTime + "毫秒");

// 解密

        lStart = System.currentTimeMillis();

        String DeString = AESOperator.getInstance().decrypt(enString);

        System.out.println("解密后的字串是：" + DeString);

        lUseTime = System.currentTimeMillis() - lStart;

        System.out.println("解密耗时：" + lUseTime + "毫秒");

    }

}