Des加密解密例子

代码如下：

package com.yanek.util;


import java.security.Key;

import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESKeySpec;
import javax.crypto.spec.IvParameterSpec;

import org.apache.commons.codec.binary.Base64;

/**
 * 运算模式CBC。

 * 在CBC模式下使用key,向量iv;

 * 对字符加密时，双方采用的都是UTF-8编码
 * @version 1.0.0
 */
public class DesUtil {

	// 向量
	private static final byte[] keyiv = { 1, 2, 3, 4, 5, 6, 7, 8 };

	/**
	 * CBC解密
	 * 
	 * @param key
	 *            密钥
	 * @param data
	 *            Base64编码的密文
	 * @return 明文
	 * @throws Exception
	 */
	public static byte[] desDecodeCBC(byte[] key, byte[] data) throws Exception {
		Key deskey = null;
		DESKeySpec spec = new DESKeySpec(key);
		SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("DES");
		deskey = keyfactory.generateSecret(spec);
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding");
		IvParameterSpec ips = new IvParameterSpec(keyiv);
		cipher.init(Cipher.DECRYPT_MODE, deskey, ips);
		byte[] bOut = cipher.doFinal(data);
		return bOut;
	}

	/**
	 * CBC解密
	 * 
	 * @param key
	 *            密钥
	 * @param data
	 *            Base64加密后的密文
	 * @return 明文
	 * @throws Exception
	 */
	public static String desDecodeCBC(String key, String data) throws Exception {
		byte[] _data = Base64.decodeBase64(data);
		byte[] _key = key.getBytes("UTF-8");
		byte[] bOut = desDecodeCBC(_key, _data);

		return new String(bOut, "UTF-8");
	}

	/**
	 * CBC加密
	 * 
	 * @param key
	 *            密钥
	 * @param data
	 *            明文
	 * @return 密文
	 * @throws Exception
	 */
	public static byte[] desEncodeCBC(byte[] key, byte[] data) throws Exception {
		Key deskey = null;
		DESKeySpec spec = new DESKeySpec(key);
		SecretKeyFactory keyfactory = SecretKeyFactory.getInstance("DES");
		deskey = keyfactory.generateSecret(spec);
		Cipher cipher = Cipher.getInstance("DES/CBC/PKCS5Padding"); // 加密方法／运算模式／填充模式
		IvParameterSpec ips = new IvParameterSpec(keyiv);
		cipher.init(Cipher.ENCRYPT_MODE, deskey, ips);
		byte[] bOut = cipher.doFinal(data);
		return bOut;
	}

	/**
	 * CBC加密
	 * 
	 * @param key
	 *            密钥
	 * @param data
	 *            明文
	 * @return Base64加密后的密文
	 * @throws Exception
	 */
	public static String desEncodeCBC(String key, String data) throws Exception {
		byte[] _data = data.getBytes("UTF-8");
		byte[] _key = key.getBytes("UTF-8");
		byte[] bOut = desEncodeCBC(_key, _data);

		return Base64.encodeBase64String(bOut); // Base64加密后的密文
	}

	public static void main(String[] args) throws Exception {

		String key = "hdhhdhdmZtmcOlmT2";
		String data = "学习测试";

		System.out.println("加密解密 测试 ");
		String str1 = desEncodeCBC(key, data);// 加密
		String str2 = desDecodeCBC(key, str1);// 解密
		System.out.println(str1);
		System.out.println(str2);

	}
}