java DES加密

package net.okdi.o2o.core.util;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 DesEncrypt {Key key;/** * 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()));//linux環境下會每次會不同，windows不會        //SecureRandom 實現嘗試完全隨機化生成器本身的內部狀態，除非調用方在調用 getInstance 方法之後又調用了 setSeed 方法：SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");        secureRandom.setSeed(strKey.getBytes());        _generator.init(secureRandom);this.key = _generator.generateKey();_generator = null;//另一种方式//KeySpec dks = new DESKeySpec(strKey.getBytes());//SecretKeyFactory keyFactory = SecretKeyFactory.getInstance("DES");//this.key = keyFactory.generateSecret(dks);} 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 = "";if(strMi!=null && !strMi.equals("")){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;}/** * 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 = Cipher.getInstance("PKCS5Padding");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 = Cipher.getInstance("PKCS5Padding");cipher.init(Cipher.DECRYPT_MODE, key);byteFina = cipher.doFinal(byteD);} catch (Exception e) {e.printStackTrace();} finally {cipher = null;}return byteFina;}    /**     * 转换密码     */public String convertPwd(String loginPwd,String type){DesEncrypt des = new DesEncrypt();// 实例化一个对像String key=ApplicationConstant.PASSWORD_KEY;des.getKey(key);if(type.equals("ENC")){loginPwd = des.getEncString(loginPwd);//加密}else{loginPwd = des.getDesString(loginPwd);//解密}return loginPwd;}public static void main(String[] args) {DesEncrypt des = new DesEncrypt();// 实例化一个对像//des.getKey("MYKEY11");// 生成密匙//System.out.println("key=MYKEY11");//String strEnc = des.getEncString("CHINA");// 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);String t = des.convertPwd("123456", "ENC");System.out.println(t);String t1 = des.convertPwd(t, "ABC");System.out.println(t1);}}