import java.io.BufferedReader;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.URL;
import java.net.URLEncoder;
import java.security.SecureRandom;
import java.util.Map;
import javax.crypto.Cipher;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.digest.DigestUtils;
 
public class Encrypt {
    /**
     * @param args
     */
    public static void main(String[] args) {
         
        //待加密內容
        String str = "1";
        //密碼8位，不足8位則用數字0補齊
        String password = "12345678";
         
        //DES加密
        byte[] result = Encrypt.desCrypto(str.getBytes(),password);
        System.out.println("DES加密後內容為："+new String(result));
        //Base64加密
        byte[] b = Base64.encodeBase64(result, true);
        System.out.println("Base64加密後內容為："+new String(b));
         
        //Base64解密
        byte[] bb = Base64.decodeBase64(b);
        System.out.println("Base64解密後內容為："+new String(bb));
        //DES解密
        try {
            byte[] decryResult = Encrypt.decrypt(bb, password);
            System.out.println("DES解密後內容為："+new String(decryResult));
        } catch (Exception e1) {
            e1.printStackTrace();
        }
    }
     
    public static String encrypt(String srcMsg, String key){
        //DES加密
        byte[] result = Encrypt.desCrypto(srcMsg.getBytes(), key);
        //Base64編碼
        byte[] resultBase = Base64.encodeBase64(result, true);
         
        return new String(resultBase);
    }
    private static byte[] desCrypto(byte[] datasource, String password) {
        try {
            SecureRandom random = new SecureRandom();
            DESKeySpec desKey = new DESKeySpec(password.getBytes());
            SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
            SecretKey securekey = keyFactory.generateSecret(desKey);
            // Cipher物件實際完成加密操作
            Cipher cipher = Cipher.getInstance("DES");
            // 用密匙初始化Cipher物件
            cipher.init(Cipher.ENCRYPT_MODE, securekey, random);
            // 現在，獲取資料並加密
            // 正式執行加密操作
            return cipher.doFinal(datasource);
        } catch (Throwable e) {
            e.printStackTrace();
        }
        return null;
    }
    private static byte[] decrypt(byte[] src, String password) throws Exception {
        // DES演算法要求有一個可信任的隨機數源
        SecureRandom random = new SecureRandom();
        // 建立一個DESKeySpec物件
        DESKeySpec desKey = new DESKeySpec(password.getBytes());
        // 建立一個密匙工廠
        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");
        // 將DESKeySpec物件轉換成SecretKey物件
        SecretKey securekey = keyFactory.generateSecret(desKey);
        // Cipher物件實際完成解密操作
        Cipher cipher = Cipher.getInstance("DES");
        // 用密匙初始化Cipher物件
        cipher.init(Cipher.DECRYPT_MODE, securekey, random);
        // 真正開始解密操作
        return cipher.doFinal(src);
    }
}