package?iweb2.ch3.collaborative.cache;

import?java.io.BufferedInputStream;
import?java.io.BufferedOutputStream;
import?java.io.File;
import?java.io.FileInputStream;
import?java.io.FileOutputStream;
import?java.io.IOException;
import?java.io.objectInputStream;
import?java.io.objectOutputStream;

/**
?*?Implementation?of?Store?interface.?Uses?files?to?store?objects
?*?using?java?serialization.?Each?object?instance?is?stored?in?a?separate?file.
?*/
public?class?FileStore?implements?Store?{

????private?File?dataDir;
????
????/**
?????*?Creates?a?new?instance?that?will?use?specified?directory?to?store?objects.
?????*?
?????*?@param?dir?directory?that?should?be?used?to?store/retrieve?objects.?
?????*/
????public?FileStore（String?dir）?{
????????this（new?File（dir））;
????}
????
????public?FileStore（File?dir）?{
????????if（?!dir.exists（）?）?{
????????????dir.mkdirs（）;
????????}
????????this.dataDir?=?dir;
????}
????
????public?boolean?exists（String?key）?{
????????File?f?=?getFile（key）;
????????return?f.exists（）;
????}

????public?object?get（String?key）?{
??????object?o?=?null;
??????try?{
??????????File?f?=?getFile（key）;
??????????if（?f.exists（）?）?{
??????????????FileInputStream?fInStream?=?new?FileInputStream（f）;
??????????????BufferedInputStream?bufInStream?=?new?BufferedInputStream（fInStream）;
??????????????objectInputStream?objInStream?=?new?objectInputStream（bufInStream）;
??????????????o?=?objInStream.readobject（）;
??????????????objInStream.close（）;
??????????}
??????}
??????catch（Exception?e）?{
??????????throw?new?RuntimeException（“Error?while?loading?data?from?file?（dir:?‘“?+?dataDir?+?“‘?filename:?‘“?+?key?+“‘）.“?e）;????????????
??????}
??????return?o;
????}

????public?void?put（String?key?object?o）?{
??????try?{
??????????File?f?=?getFile（key）;
??????????FileOutputStream?foutStream?=?new?FileOutputStream（f）;
??????????BufferedOutputStream?boutStream?=?new?BufferedOutputStream（foutStream）;
??????????objectOutputStream?objOutputStream?=?new?objectOutputStream（boutStream）;
??????????objOutputStream.writeobject（o）;
??????????objOutputStream.flush（）;
??????????boutStream.close（）;
??????}
??????catch（IOException?e）?{
??????????throw?new?RuntimeException（“Error?while?saving?data?into?file?（dir:?‘“?+?dataDir?+?“‘?filename:?‘“?+?key?+“‘）.“?e）;?????????
??????}
????}
????
????public?void?remove（String?key）?{
????????File?f?=?getFile（key）;
????????if（?f.exists（）?）?{
????????????f.delete（）;
????????}
????}

????/*
?????*?Derives?filename?from?the?key?and?returns?instance?of?File
?????*/
????private?File?getFile（String?key）?{
????????//?key?is?used?as?a?filename
????????return?new?File（dataDir?key?+?“.tmp“）;
????}
}

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2014-03-23?21:12??Recommend\
?????目錄???????????0??2014-03-23?21:12??Recommend\src\
?????目錄???????????0??2014-03-23?21:11??Recommend\src\collaborative\
?????目錄???????????0??2014-03-23?21:11??Recommend\src\collaborative\cache\
?????文件????????2770??2010-04-30?10:42??Recommend\src\collaborative\cache\FileStore.java
?????文件?????????898??2010-04-30?10:42??Recommend\src\collaborative\cache\Store.java
?????目錄???????????0??2014-03-23?21:11??Recommend\src\collaborative\data\
?????文件???????11755??2010-04-30?10:42??Recommend\src\collaborative\data\baseDataset.java
?????文件?????????702??2010-04-30?10:42??Recommend\src\collaborative\data\ContentItem.java
?????文件???????12550??2010-04-30?10:42??Recommend\src\collaborative\data\DiggData.java
?????文件????????2174??2010-04-30?10:42??Recommend\src\collaborative\data\HTMLContent.java
?????文件????????1745??2011-01-19?14:34??Recommend\src\collaborative\data\MovieLensData.java
?????文件???????11574??2010-04-30?10:42??Recommend\src\collaborative\data\MovieLensDataset.java
?????文件????????9630??2010-04-30?10:42??Recommend\src\collaborative\data\MusicData.java
?????文件?????????707??2010-04-30?10:42??Recommend\src\collaborative\data\MusicItem.java
?????文件?????????393??2010-04-30?10:42??Recommend\src\collaborative\data\MusicRating.java
?????文件????????7160??2010-10-07?16:06??Recommend\src\collaborative\data\MusicUser.java
?????文件????????6370??2010-04-30?10:42??Recommend\src\collaborative\data\NewsData.java
?????文件?????????549??2010-04-30?10:42??Recommend\src\collaborative\data\NewsItem.java
?????文件?????????875??2010-04-30?10:42??Recommend\src\collaborative\data\NewsUser.java
?????文件????????1718??2010-04-30?10:42??Recommend\src\collaborative\data\RatingBuilder.java
?????目錄???????????0??2014-03-23?21:11??Recommend\src\collaborative\evaluation\
?????文件?????????379??2010-04-30?10:42??Recommend\src\collaborative\evaluation\EvaluationDataProvider.java
?????文件????????8477??2010-04-30?10:42??Recommend\src\collaborative\evaluation\MovieLensEvaluationDataProvider.java
?????文件????????2202??2011-01-19?18:17??Recommend\src\collaborative\evaluation\MovieLensRMSE.java
?????文件????????5521??2011-01-19?11:04??Recommend\src\collaborative\evaluation\RMSEEstimator.java
?????文件????????1353??2010-04-30?10:42??Recommend\src\collaborative\evaluation\RMSEResult.java
?????目錄???????????0??2014-03-23?21:11??Recommend\src\collaborative\model\
?????文件????????4787??2010-04-30?10:42??Recommend\src\collaborative\model\Content.java
?????文件????????2517??2010-04-30?10:42??Recommend\src\collaborative\model\Dataset.java
?????文件????????3888??2010-04-30?10:42??Recommend\src\collaborative\model\Item.java
............此處省略41個文件信息