DES.java

package com.juns.wechat.common;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

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

public class DES {
	private static byte[] iv = { 1, 2, 3, 4, 5, 6, 7, 8 };
	public static String strkey = "%%d";

	/**
	 * 数据加密
	 * 
	 * @param encryptString
	 * @return
	 * @throws Exception
	 */
	public static String encryptDES(String encryptString) throws Exception {
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(getkeys().getBytes(), "DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.ENCRYPT_MODE, key, zeroIv);
		byte[] encryptedData = cipher.doFinal(encryptString.getBytes());
		return BASE64.encode(encryptedData);
	}

	/**
	 * 数据解密
	 * 
	 * @param decryptString
	 * @return
	 * @throws Exception
	 */
	public static String decryptDES(String decryptString) throws Exception {
		byte[] byteMi = new BASE64().decode(decryptString);
		IvParameterSpec zeroIv = new IvParameterSpec(iv);
		SecretKeySpec key = new SecretKeySpec(getkeys().getBytes(), "DES");
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		cipher.init(Cipher.DECRYPT_MODE, key, zeroIv);
		byte decryptedData[] = cipher.doFinal(byteMi);
		return new String(decryptedData);
	}

	public static String getkeys() {
		return BASE64.strkey2;
	}

	// MD5加密
	private static final char HEX_DIGITS[] = { '0', '1', '2', '3', '4', '5',
			'6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
	public static String strkey3 = "*(&";

	public static String toHexString(byte[] b) { // String to byte
		StringBuilder sb = new StringBuilder(b.length * 2);
		for (int i = 0; i < b.length; i++) {
			sb.append(HEX_DIGITS[(b[i] & 0xf0) >>> 4]);
			sb.append(HEX_DIGITS[b[i] & 0x0f]);
		}
		return sb.toString();
	}

	public static String md5(String s) {
		try {
			// Create MD5 Hash
			MessageDigest digest = java.security.MessageDigest
					.getInstance("MD5");
			digest.update(s.getBytes());
			byte[] messageDigest = digest.digest();
			return toHexString(messageDigest).toLowerCase();
		} catch (NoSuchAlgorithmException e) {
			e.printStackTrace();
			return "";
		}
	}

	/**
	 * 密码MD5 调用此方法
	 * 
	 * @param s
	 * @return
	 */
	public static String md5Pwd(String s) {
		return md5("hJy*()" + s);
	}
}