package com.xcong.excoin.utils;

import java.security.Key;

import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;


public class DES {
    static String string = "DES";
    public static void main(String[] args) {
        DES.jdkDES();
    }

    public static void jdkDES() {

        try {

            // 生成key//返回生成指定算法密钥的KeyGenerator对象
            KeyGenerator keyGenerator = KeyGenerator.getInstance("DES");
            keyGenerator.init(56);//初始化此密钥生成器,使其具有确定的密钥大小
            SecretKey secretKey = keyGenerator.generateKey();//生成一个密钥
            byte[] bs = secretKey.getEncoded();

            // key转换
            DESKeySpec desKeySpec = new DESKeySpec(bs); //实例化DES密钥规则
            SecretKeyFactory factory = SecretKeyFactory.getInstance("DES"); //实例化密钥工厂
            Key convertSecretKey = factory.generateSecret(desKeySpec); //生成密钥

            // 加密
            Cipher cipher = Cipher.getInstance("DES/ECB/PKCS5Padding");
            cipher.init(Cipher.ENCRYPT_MODE, convertSecretKey);
            byte[] result = cipher.doFinal(string.getBytes());
            System.out.println("jdk des encrypt:" + DESUtil.byteToHex(result));

            // 解密
            cipher.init(Cipher.DECRYPT_MODE, convertSecretKey);
            result = cipher.doFinal(result);
            System.out.println("jdk des decrypt:" + new String(result));
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
    }
}