DES加密、解密字符串算法(java版)

　　DESPlus.java package com.des; import java.security.*; import javax.crypto.*; public class DESPlus { private static String strDefaultKey = "national"; private Cipher encryptCipher = null; private Cipher decryptCipher = null; public 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 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 * @author LiGuoQing */ public 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 字符串 * * @param strIn * 需加密的字符串 * @return 加密后的字符串 * @throws Exception */ public String encrypt(String strIn) throws Exception { return byteArr2HexStr(encrypt(strIn.getBytes())); } public byte[] decrypt(byte[] arrB) throws Exception { return decryptCipher.doFinal(arrB); } public String decrypt(String strIn) throws Exception { return new String(decrypt(hexStr2ByteArr(strIn))); } 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; } } 测试程序 Test.java package com.des; public class Test { public static void main(String[] args) { // TODO Auto-generated method stub try { String test = "Hellow Word!"; //DESPlus des = new DESPlus();//默认密钥 DESPlus des = new DESPlus("leemenz");//自定义密钥 System.out.println("加密前的字符："+test); System.out.println("加密后的字符："+des.encrypt(test)); System.out.println("解密后的字符："+des.decrypt(des.encrypt(test))); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } } }