DES加解密操作

package com.demo.wnb;

import java.security.NoSuchAlgorithmException;
import java.security.Security;

import javax.crypto.Cipher;
import javax.crypto.NoSuchPaddingException;
import javax.crypto.spec.SecretKeySpec;

import com.sun.crypto.provider.SunJCE;
/**
 * DES加解密demo
 * 處理字符串加密解密的公用類
 * @author wnb
 */
public class Des {
	
	@SuppressWarnings("unused")
	private static final String Algorithm = "DESede";
	
	public Des() {
		
	}

	/**
	 * 加密模式
	 * @param keybyte
	 * @param src
	 * @return
	 */
	private static byte[] encryptMode(byte keybyte[], byte src[]) {
		try {
			javax.crypto.SecretKey deskey = new SecretKeySpec(keybyte, "DESede");
			Cipher c1 = Cipher.getInstance("DESede");
			c1.init(1, deskey);
			return c1.doFinal(src);
		} catch (NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	/**
	 * 解密模式
	 * @param keybyte
	 * @param src
	 * @return
	 */
	private static byte[] decryptMode(byte keybyte[], byte src[]) {
		try {
			javax.crypto.SecretKey deskey = new SecretKeySpec(keybyte, "DESede");
			Cipher c1 = Cipher.getInstance("DESede");
			c1.init(2, deskey);
			return c1.doFinal(src);
		} catch (NoSuchAlgorithmException e1) {
			e1.printStackTrace();
		} catch (NoSuchPaddingException e2) {
			e2.printStackTrace();
		} catch (Exception e3) {
			e3.printStackTrace();
		}
		return null;
	}

	private static String byte2hex(byte b[]) {
		String hs = "";
		String stmp = "";
		for (int n = 0; n < b.length; n++) {
			stmp = Integer.toHexString(b[n] & 0xff);
			if (stmp.length() == 1)
				hs = hs + "0" + stmp;
			else
				hs = hs + stmp;
		}

		return hs.toUpperCase();
	}

	public static byte[] hex2byte(String hex) throws IllegalArgumentException {
		if (hex.length() % 2 != 0)
			throw new IllegalArgumentException();
		char arr[] = hex.toCharArray();
		byte b[] = new byte[hex.length() / 2];
		int i = 0;
		int j = 0;
		for (int l = hex.length(); i < l;) {
			String swap = "" + arr[i++] + arr[i];
			int byteint = Integer.parseInt(swap, 16) & 0xff;
			b[j] = (new Integer(byteint)).byteValue();
			i++;
			j++;
		}

		return b;
	}
	
	/**
	 * 字符串加密
	 * @param sourceCode 要加密的字符串
	 * @return
	 */
	public static String encryptIt(String sourceCode) {
		Security.addProvider(new SunJCE());
		//祕鑰（des對稱加密算法，加解密祕鑰一樣）
		byte keyBytes[] = { 17, 34, 79, 88, -120, 16, 64, 56, 40, 37, 121, 81,
				-53, -35, 85, 102, 119, 41, 116, -104, 48, 64, 54, -30 };
		byte encoded[] = encryptMode(keyBytes, sourceCode.getBytes());
		return byte2hex(encoded);
	}
	
	/**
	 * 字符串解密
	 * @param encodedCode 要解密的字符串
	 * @return
	 */
	public static String decryptIt(String encodedCode) {
		Security.addProvider(new SunJCE());
		//祕鑰（des對稱加密算法，加解密祕鑰一樣）
		byte keyBytes[] = { 17, 34, 79, 88, -120, 16, 64, 56, 40, 37, 121, 81,
				-53, -35, 85, 102, 119, 41, 116, -104, 48, 64, 54, -30 };
		byte encoded[] = decryptMode(keyBytes, hex2byte(encodedCode));
		return new String(encoded);
	}
	
	public static void main(String args[]) {
		String str="1234";
		String str1 = encryptIt(str);
		System.out.println("加密1234:" + str1);
		
		String str2 = decryptIt("ED94C2C049B041FD");
		if(str.equals(str2)){
			System.out.println("加密解密成功了");
		}
		
		System.out.println("解密19A455DB854230E28AD1ED4C646341BE:"+decryptIt("19A455DB854230E28AD1ED4C646341BE"));
	}
	
}