import?org.apache.commons.codec.binary.base64;

import?java.util.Arrays;
import?java.util.Random;

import?javax.crypto.Cipher;
import?javax.crypto.spec.IvParameterSpec;
import?javax.crypto.spec.SecretKeySpec;

/**
?*?@title:?WXPublicUtils.java
?*?@Description:?提供接收和推送給公眾平臺消息的加解密接口（UTF8編碼的字符串）
?*?@Author:?xj
?*/
/**
?*?

?*?	
第三方回復加密消息給公眾平臺

?*?	
第三方收到公眾平臺發送的消息，驗證消息的安全性，并對消息進行解密。

?*?

?*?說明：異常java.security.InvalidKeyException:illegal?Key?Size的解決方案
?*?

?*?	
在官方網站下載JCE無限制權限策略文件（JDK7的下載地址：
?*??????http://www.oracle.com/technetwork/java/javase/downloads/jce-7-download-432124.html

?*?	
下載后解壓，可以看到local_policy.jar和US_export_policy.jar以及readme.txt

?*?	
如果安裝了JRE，將兩個jar文件放到%JRE_HOME%\lib\security目錄下覆蓋原來的文件

?*?	
如果安裝了JDK，將兩個jar文件放到%JDK_HOME%\jre\lib\security目錄下覆蓋原來文件

?*?

?*/
public?class?WXPublicUtils?{

????private?static?base64?base64?=?new?base64（）;

????//?生成4個字節的網絡字節序
????private?static?byte[]?getNetworkBytesOrder（int?sourceNumber）?{
????????byte[]?orderBytes?=?new?byte[4];
????????orderBytes[3]?=?（byte）?（sourceNumber?&?0xFF）;
????????orderBytes[2]?=?（byte）?（sourceNumber?>>?8?&?0xFF）;
????????orderBytes[1]?=?（byte）?（sourceNumber?>>?16?&?0xFF）;
????????orderBytes[0]?=?（byte）?（sourceNumber?>>?24?&?0xFF）;
????????return?orderBytes;
????}

????//?還原4個字節的網絡字節序
????private?static?int?recoverNetworkBytesOrder（byte[]?orderBytes）?{
????????int?sourceNumber?=?0;
????????for?（int?i?=?0;?i?????????????sourceNumber?<<=?8;
????????????sourceNumber?|=?orderBytes[i]?&?0xff;
????????}
????????return?sourceNumber;
????}

????//?隨機生成16位字符串
????public?static?String?getRandomStr（）?{
????????String?base?=?“ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789“;
????????Random?random?=?new?Random（）;
????????StringBuffer?sb?=?new?StringBuffer（）;
????????for?（int?i?=?0;?i?????????????int?number?=?random.nextInt（base.length（））;
????????????sb.append（base.charAt（number））;
????????}
????????return?sb.toString（）;
????}

????/**
?????*?對明文進行加密.
?????*
?????*?@param?randomStr?隨機字符串
?????*?@param?text?需要加密的明文
?????*?@return?加密后base64編碼的字符串
?????*?@throws?AesException?aes加密失敗
?????*/
????public?static?String?encrypt（String?randomStr?String?text）?throws?AesException?{
????????ByteGroup?byteCollector?=?new?ByteGroup（）;
????????byte[]?randomStrBytes?=?randomStr.getBytes（WXConstants.CHARSET）;
????????byte[]?textBytes?=?text.getBytes（WXConstants.CHARSET）;
????????byte[]?networkBytesOrder?=?getNetworkBytesOrder（textBytes.length）;
????????byte[]?appidBytes?=?WXConstants.APPID.getBytes（WXConstants.CHARSET）;

????????//?randomStr?+?networkBytesOrder?+?text?+?appid
????????byteCollector.addBytes（randomStrBytes）;
????????byteCollector.addBytes（networkBytesOrder）;
????????byteCollector.addBytes（textBytes）;
????????byteCollector.addBytes（appidBytes）;

????????//?...?+?pad:?使用自定義的填充方式對明文進行補位填充
????????byte[]?padBytes?=

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-06-11?17:14??aes\
?????文件????????1723??2018-06-11?17:17??aes\AesException.java
?????文件?????????627??2018-06-11?17:18??aes\ByteGroup.java
?????文件????????1479??2018-06-11?17:18??aes\PKCS7Encoder.java
?????文件????????2958??2018-06-11?17:18??aes\SHA1.java
?????文件????????2016??2018-06-11?17:19??aes\xmlParse.java
?????文件???????11061??2018-06-11?17:20??WXPublicUtils.java