import javax.crypto.Cipher;  
import javax.crypto.SecretKey;  
import javax.crypto.spec.SecretKeySpec;  
import java.io.ByteArrayOutputStream;  
import java.security.Security;  
  
/** 
 * Created by xiang.li on 2015/3/19. 
 * TripleDES(3DES) 加解密工具类 
 */  
public class TripleDES {  
    private static final String Algorithm = "DESede"; // 定义 加密算法,可用 DES,DESede,Blowfish  
    private static final String hexString="0123456789ABCDEF";  
    /** 
     * 
     * @param keybyte  加密密钥，长度为24字节 
     * @param src     字节数组(根据给定的字节数组构造一个密钥。 ) 
     * @return 
     */  
    public static byte[] encryptMode(byte[] keybyte, byte[] src) {  
        try {  
            // 根据给定的字节数组和算法构造一个密钥  
            SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);  
            // 加密  
            Cipher c1 = Cipher.getInstance(Algorithm);  
            c1.init(Cipher.ENCRYPT_MODE, deskey);  
            return c1.doFinal(src);  
        } catch (java.security.NoSuchAlgorithmException e1) {  
            e1.printStackTrace();  
        } catch (javax.crypto.NoSuchPaddingException e2) {  
            e2.printStackTrace();  
        } catch (java.lang.Exception e3) {  
            e3.printStackTrace();  
        }  
        return null;  
    }  
  
    /** 
     * 
     * @param keybyte 密钥 
     * @param src       需要解密的数据 
     * @return 
     */  
    public static byte[] decryptMode(byte[] keybyte, byte[] src) {  
        try {  
            // 生成密钥  
            SecretKey deskey = new SecretKeySpec(keybyte, Algorithm);  
            // 解密  
            Cipher c1 = Cipher.getInstance(Algorithm);  
            c1.init(Cipher.DECRYPT_MODE, deskey);  
            return c1.doFinal(src);  
        } catch (java.security.NoSuchAlgorithmException e1) {  
            e1.printStackTrace();  
        } catch (javax.crypto.NoSuchPaddingException e2) {  
            e2.printStackTrace();  
        } catch (java.lang.Exception e3) {  
            e3.printStackTrace();  
        }  
        return null;  
    }  
  
    /** 
     * 字符串转为16进制 
     * @param str 
     * @return 
     */  
    public static String encode(String str)  
    {  
        //根据默认编码获取字节数组  
        byte[] bytes=str.getBytes();  
        StringBuilder sb=new StringBuilder(bytes.length*2);  
  
        //将字节数组中每个字节拆解成2位16进制整数  
        for(int i=0;i<bytes.length;i++)  
        {  
            sb.append(hexString.charAt((bytes[i]&0xf0)>>4));  
            sb.append(hexString.charAt((bytes[i]&0x0f)>>0));  
        }  
        return sb.toString();  
    }  
    /** 
     * 
     * @param bytes 
     * @return 
     * 将16进制数字解码成字符串,适用于所有字符（包括中文） 
     */  
    public static String decode(String bytes)  
    {  
        ByteArrayOutputStream baos=new ByteArrayOutputStream(bytes.length()/2);  
        //将每2位16进制整数组装成一个字节  
        for(int i=0;i<bytes.length();i+=2)  
            baos.write((hexString.indexOf(bytes.charAt(i))<<4 |hexString.indexOf(bytes.charAt(i+1))));  
        return new String(baos.toByteArray());  
    }  
  
    // 转换成十六进制字符串  
    public static String byte2hex(byte[] b) {  
        String hs = "";  
        String stmp = "";  
        for (int n = 0; n < b.length; n++) {  
            stmp = (java.lang.Integer.toHexString(b[n] & 0XFF));  
            if (stmp.length() == 1)  
                hs = hs + "0" + stmp;  
            else  
                hs = hs + stmp;  
            if (n < b.length - 1)  
                hs = hs + "";  
        }  
        return hs.toUpperCase();  
    }  
  
    public static void main(String[] args) {  
        // 添加新安全算法,如果用JCE就要把它添加进去  
        //这里addProvider方法是增加一个新的加密算法提供者(个人理解没有找到好的答案,求补充)  
        Security.addProvider(new com.sun.crypto.provider.SunJCE());  
        //byte数组(用来生成密钥的)  
        final byte[] keyBytes = { 0x11, 0x22, 0x4F, 0x58, (byte)0x88, 0x10,  
                0x40, 0x38, 0x28, 0x25, 0x79, 0x51, (byte) 0xCB, (byte) 0xDD,  
                0x55, 0x66, 0x77, 0x29, 0x74, (byte) 0x98, 0x30, 0x40, 0x36,  
                (byte) 0xE2 };  
        String szSrc = "This is a 3DES test. 测试";  
        System.out.println("加密前的字符串:" + szSrc);  
  
        byte[] encoded = encryptMode(keyBytes, szSrc.getBytes());  
        System.out.println("加密后的字符串:" + byte2hex(encoded));  
  
        byte[] srcBytes = decryptMode(keyBytes, encoded);  
        System.out.println("解密后的字符串:" + new String(srcBytes));  
    }  
}