JCE设置秘钥加密解密

一、EncryptionDecryption.java

package com.x.util;import java.security.Key;import java.security.Provider;import java.security.Security;import javax.crypto.Cipher;import org.apache.log4j.Logger;public class EncryptionDecryption {private static final Logger log = Logger.getLogger(EncryptionDecryption.class);private static String strDefaultKey = "assignKey";/** 加密工具 */private Cipher encryptCipher = null;/** 解密工具 */private Cipher decryptCipher = null;/**   * 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   *     */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   *   */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 EncryptionDecryption(){this(strDefaultKey);}/**   * 指定密钥构造方法   *   * @param strKey   * 指定的密钥   * @throws Exception   */public EncryptionDecryption(String strKey){try{//修改使之兼容maven打包Class c = Class.forName("com.sun.crypto.provider.SunJCE");Provider provider = (Provider)c.newInstance();Security.addProvider(provider);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);}catch(Exception e){log.info("-------------------加密类EncryptionDecryption加载失败---------------------");}}/**   * 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   */public 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   */public String decrypt(String strIn) throws Exception {try {return new String(decrypt(hexStr2ByteArr(strIn)));} catch (Exception e) {e.printStackTrace();return "";}}/**   * 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){String aa = "11M111AJ";try {EncryptionDecryption ed = new EncryptionDecryption();System.out.println(ed.encrypt(aa));System.out.println(ed.decrypt(ed.encrypt(aa)));} catch (Exception e) { }}}