package?cn.com.csii.utility;

import?java.io.ByteArrayInputStream;
import?java.io.ByteArrayOutputStream;
import?java.io.File;
import?java.io.FileInputStream;
import?java.io.FileOutputStream;
import?java.io.InputStream;
import?java.io.OutputStream;
?
import?org.apache.commons.codec.binary.base64;
?
/**
?*?

?*?base64編碼解碼工具包
?*?

?*?

?*?依賴javabase64-1.3.1.jar
?*?

?*?
?*?@author?IceWee
?*?@date?2012-5-19
?*?@version?1.0
?*/
public?class?base64Utils?{
?
????/**
?????*?文件讀取緩沖區大小
?????*/
????private?static?final?int?CACHE_SIZE?=?1024;
?????
????/**
?????*?

?????*?base64字符串解碼為二進制數據
?????*?

?????*?
?????*?@param?base64
?????*?@return
?????*?@throws?Exception
?????*/
????public?static?byte[]?decode（String?base64）?throws?Exception?{
????	base64?base64In?=?new?base64（）;
????????return?base64In.decode（base64.getBytes（））;
????}
?????
????/**
?????*?

?????*?二進制數據編碼為base64字符串
?????*?

?????*?
?????*?@param?bytes
?????*?@return
?????*?@throws?Exception
?????*/
????public?static?String?encode（byte[]?bytes）?throws?Exception?{
????	base64?base64In?=?new?base64（）;
????????return?new?String（base64In.encode（bytes））;
????}
?????
????/**
?????*?

?????*?將文件編碼為base64字符串
?????*?

?????*?

?????*?大文件慎用，可能會導致內存溢出
?????*?

?????*?
?????*?@param?filePath?文件絕對路徑
?????*?@return
?????*?@throws?Exception
?????*/
????public?static?String?encodeFile（String?filePath）?throws?Exception?{
????????byte[]?bytes?=?fileToByte（filePath）;
????????return?encode（bytes）;
????}
?????
????/**
?????*?

?????*?base64字符串轉回文件
?????*?

?????*?
?????*?@param?filePath?文件絕對路徑
?????*?@param?base64?編碼字符串
?????*?@throws?Exception
?????*/
????public?static?void?decodeToFile（String?filePath?String?base64）?throws?Exception?{
????????byte[]?bytes?=?decode（base64）;
????????byteArrayToFile（bytes?filePath）;
????}
?????
????/**
?????*?

?????*?文件轉換為二進制數組
?????*?

?????*?
?????*?@param?filePath?文件路徑
?????*?@return
?????*?@throws?Exception
?????*/
????public?static?byte[]?fileToByte（String?filePath）?throws?Exception?{
????????byte[]?data?=?new?byte[0];
????????File?file?=?new?File（filePath）;
????????if?（file.exists（））?{
????????????FileInputStream?in?=?new?FileInputStream（file）;
????????????ByteArrayOutputStream?out?=?new?ByteArrayOutputStream（2048）;
????????????byte[]?cache?=?new?byte[CACHE_SIZE];
????????????int?nRead?=?0;
????????????while?（（nRead?=?in.read（cache））?!=?-1）?{
????????????????out.write（cache?0?nRead）;
????????????????out.flush（）;
????????????}
????????????out.close（）;
????????????in.close（）;
????????????data?=?out.toByteArray（）;
?????????}
????????return?data;
????}
?????
????/**
?????*?

?????*?二進制數據寫文件
?????*?

?????*?
?????*?@param?bytes?二進制數據
?????*?@param?filePath?文件生成目錄
?????*/
????public?static?void?byteArrayToFile（byte[]?bytes?String?filePath）?throws?Exception?{
????????InputStream?in?=?new?ByteArrayInputStream（by

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????3647??2016-02-18?16:56??base64Utils.java
?????文件???????10507??2016-02-18?16:21??RSAUtils.java