Java DES 加解密（支持utf-8）

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import java.security.Key;
import java.security.Security;

import javax.crypto.Cipher;

public class DESCrypt {
	private static String strDefaultKey = "goodluck";

	private Cipher encryptCipher = null;
	private Cipher decryptCipher = null;

	/**
	 * 暗号化 明文入力String 密文出力

	 * @param strMing
	 *            明文
	 * @return 密文
	 * @throws Exception
	 */
	public String getEncString(String strMing) throws Exception {
		return byteArr2HexStr(encrypt(strMing.getBytes("UTF8")));
	}

	/**
	 * 解密 String密文入力,String明文出力

	 * 
	 * 
	 * @param strMi
	 *            密文
	 * @return 明文
	 * @throws Exception
	 */
	public String getDesString(String strMi) throws Exception {
		return new String(decrypt(hexStr2ByteArr(strMi)),"UTF8");
	}
	
	public String getDesStr(String strMi)  {
		String ming=null;
		try {
			ming= new String(decrypt(hexStr2ByteArr(strMi)),"UTF8");
		} catch (Exception e) {
			ming = strMi;
		}
		return ming;
	}

	/**
	 * 将byte数组转换为表示16进制值的字符串， 如：byte[]{8,18}转换为：0813， 和public static byte[]
	 * hexStr2ByteArr(String strIn) 互为可逆的转换过程

	 * 
	 * @param arrB
	 *            需要转换的byte数组

	 * @return 转换后的字符串
	 * @throws Exception
	 *             本方法不处理任何异常，所有异常全部抛出
	 */
	private static String byteArr2HexStr(byte[] arrB) throws Exception {
		int iLen = arrB.length;
		// 每个byte用两个字符才能表示，所以字符串的长度是数组长度的两倍

		StringBuffer sb = new StringBuffer(iLen * 2);
		for (int i = 0; i < iLen; i++) {
			int intTmp = arrB[i];
			// 把负数转换为正数
			while (intTmp < 0) {
				intTmp = intTmp + 256;
			}
			// 小于0F的数需要在前面补0
			if (intTmp < 16) {
				sb.append("0");
			}
			sb.append(Integer.toString(intTmp, 16));
		}
		return sb.toString();
	}

	/**
	 * 将表示16进制值的字符串转换为byte数组， 和public static String byteArr2HexStr(byte[] arrB)
	 * 互为可逆的转换过程

	 * 
	 * @param strIn
	 *            需要转换的字符串
	 * @return 转换后的byte数组

	 * @throws Exception
	 *             本方法不处理任何异常，所有异常全部抛出
	 */
	private static byte[] hexStr2ByteArr(String strIn) throws Exception {
		byte[] arrB = strIn.getBytes();
		int iLen = arrB.length;

		// 两个字符表示一个字节，所以字节数组长度是字符串长度除以2
		byte[] arrOut = new byte[iLen / 2];
		for (int i = 0; i < iLen; i = i + 2) {
			String strTmp = new String(arrB, i, 2);
			arrOut[i / 2] = (byte) Integer.parseInt(strTmp, 16);
		}
		return arrOut;
	}

	/**
	 * 默认构造方法，使用默认密钥
	 * 
	 * @throws Exception
	 */
	public DESCrypt() throws Exception {
		this(strDefaultKey);
	}

	/**
	 * 指定密钥构造方法

	 * 
	 * @param strKey
	 *            指定的密钥
	 * @throws Exception
	 */
	public DESCrypt(String strKey) throws Exception {
		Security.addProvider(new com.sun.crypto.provider.SunJCE());
		Key key = getKey(strKey.getBytes());

		encryptCipher = Cipher.getInstance("DES");
		encryptCipher.init(Cipher.ENCRYPT_MODE, key);

		decryptCipher = Cipher.getInstance("DES");
		decryptCipher.init(Cipher.DECRYPT_MODE, key);
	}

	/**
	 * 加密字节数组

	 * 
	 * @param arrB
	 *            需加密的字节数组

	 * @return 加密后的字节数组

	 * @throws Exception
	 */
	private byte[] encrypt(byte[] arrB) throws Exception {
		return encryptCipher.doFinal(arrB);
	}

	/**
	 * 加密字符串
	 * 
	 * @param strIn
	 *            需加密的字符串
	 * @return 加密后的字符串
	 * @throws Exception
	 */
	private String encrypt(String strIn) throws Exception {
		return byteArr2HexStr(encrypt(strIn.getBytes()));
	}

	/**
	 * 解密字节数组

	 * 
	 * @param arrB
	 *            需解密的字节数组

	 * @return 解密后的字节数组

	 * @throws Exception
	 */
	private byte[] decrypt(byte[] arrB) throws Exception {
		return decryptCipher.doFinal(arrB);
	}

	/**
	 * 解密字符串
	 * 
	 * @param strIn
	 *            需解密的字符串
	 * @return 解密后的字符串
	 * @throws Exception
	 */
	private String decrypt(String strIn) throws Exception {
		return new String(decrypt(hexStr2ByteArr(strIn)));
	}

	/**
	 * 从指定字符串生成密钥，密钥所需的字节数组长度为8位 不足8位时后面补0，超出8位只取前8位

	 * 
	 * @param arrBTmp
	 *            构成该字符串的字节数组

	 * @return 生成的密钥
	 * @throws java.lang.Exception
	 */
	private Key getKey(byte[] arrBTmp) throws Exception {
		// 创建一个空的8位字节数组（默认值为0）

		byte[] arrB = new byte[8];

		// 将原始字节数组转换为8位

		for (int i = 0; i < arrBTmp.length && i < arrB.length; i++) {
			arrB[i] = arrBTmp[i];
		}

		// 生成密钥
		Key key = new javax.crypto.spec.SecretKeySpec(arrB, "DES");

		return key;
	}

	public static void main(String[] args) throws Exception {
		DESCrypt des = new DESCrypt();
		String str1 = "长子";
		// DES加密


		String str2 = des.getEncString(str1);
		String deStr = des.getDesString(str2);
		System.out.println("密文:" + str2);
		// DES解密


		System.out.println("明文:" + deStr);

	}
}

法2

import java.security.Key;
import java.security.SecureRandom;
import javax.crypto.Cipher;
import javax.crypto.KeyGenerator;

import sun.misc.BASE64Decoder;
import sun.misc.BASE64Encoder;

/**
 * 
 * 使用DES加密与解密,可对byte[],String类型进行加密与解密 密文可使用String,byte[]存储.
 * 
 * 方法: void getKey(String strKey)从strKey的字条生成一个Key
 * 
 * String getEncString(String strMing)对strMing进行加密,返回String密文 String
 * getDesString(String strMi)对strMin进行解密,返回String明文
 * 
 * byte[] getEncCode(byte[] byteS)byte[]型的加密 byte[] getDesCode(byte[]
 * byteD)byte[]型的解密
 */

public class DESCrypt {
	Key key;
	private static String strDefaultKey = "goodluck";
	public DESCrypt(){
		getKey(strDefaultKey);
	}
	/**
	 * 根据参数生成KEY
	 * 
	 * @param strKey
	 */
	public  void getKey(String strKey) {
		try {
			KeyGenerator _generator = KeyGenerator.getInstance("DES");
			_generator.init(new SecureRandom(strKey.getBytes()));
			this.key = _generator.generateKey();
			_generator = null;
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 加密String明文输入,String密文输出
	 * 
	 * @param strMing
	 * @return
	 */
	public String getEncString(String strMing) {
		byte[] byteMi = null;
		byte[] byteMing = null;
		String strMi = "";
		BASE64Encoder base64en = new BASE64Encoder();
		try {
			byteMing = strMing.getBytes("UTF8");
			byteMi = this.getEncCode(byteMing);
			strMi = base64en.encode(byteMi);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			base64en = null;
			byteMing = null;
			byteMi = null;
		}
		return strMi;
	}

	/**
	 * 解密 以String密文输入,String明文输出
	 * 
	 * @param strMi
	 * @return
	 */
	public String getDesString(String strMi) {
		BASE64Decoder base64De = new BASE64Decoder();
		byte[] byteMing = null;
		byte[] byteMi = null;
		String strMing = "";
		try {
			byteMi = base64De.decodeBuffer(strMi);
			byteMing = this.getDesCode(byteMi);
			strMing = new String(byteMing, "UTF8");
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			base64De = null;
			byteMing = null;
			byteMi = null;
		}
		return strMing;
	}

	public String getDesStr(String strMi) {
		BASE64Decoder base64De = new BASE64Decoder();
		byte[] byteMing = null;
		byte[] byteMi = null;
		String strMing = "";
		try {
			byteMi = base64De.decodeBuffer(strMi);
			byteMing = this.getDesCode(byteMi);
			strMing = new String(byteMing, "UTF8");
		} catch (Exception e) {
			//e.printStackTrace();
			strMing = strMi;
		} finally {
			base64De = null;
			byteMing = null;
			byteMi = null;
		}
		return strMing;
	}

	/**
	 * 加密以byte[]明文输入,byte[]密文输出
	 * 
	 * @param byteS
	 * @return
	 */
	private byte[] getEncCode(byte[] byteS) {
		byte[] byteFina = null;
		Cipher cipher;
		try {
			cipher = Cipher.getInstance("DES");
			cipher.init(Cipher.ENCRYPT_MODE, key);
			byteFina = cipher.doFinal(byteS);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			cipher = null;
		}
		return byteFina;
	}

	/**
	 * 解密以byte[]密文输入,以byte[]明文输出
	 * 
	 * @param byteD
	 * @return
	 */
	private byte[] getDesCode(byte[] byteD) {
		Cipher cipher;
		byte[] byteFina = null;
		try {
			cipher = Cipher.getInstance("DES");
			cipher.init(Cipher.DECRYPT_MODE, key);
			byteFina = cipher.doFinal(byteD);
		} catch (Exception e) {
			e.printStackTrace();
		} finally {
			cipher = null;
		}
		return byteFina;

	}

	public static void main(String[] args) {

		System.out.println("des demo");
		DESCrypt des = new DESCrypt();// 实例化一个对像
		//des.getKey("MYKEY11");// 生成密匙
		//System.out.println("key=MYKEY11");
		String strEnc = des.getEncString("测试一下试试！");// 加密字符串,返回String的密文
		System.out.println("密文=" + strEnc);

		String strDes = des.getDesString(strEnc);// 把String 类型的密文解密
		System.out.println("明文=" + strDes);

	}

}