原生Android缩略图填满SD卡的问题
16lz
2021-01-23
From:http://blog.csdn.net/fengye810130/article/details/9118221
google原生Android中，MiniThumbFile.java里存储图片/视频的缩略图的算法有问题。 该算法的漏洞造成微缩略图文件（ DCIM\.thumbnails\.thumbdata4--1967290299 ）非常庞大和臃肿，多达1G，理论上可以无限大，直到填满SD卡 重现步骤： 第一步 ：插入一张拥有10万张图片的外部ＳＤ卡， 第二步 ：等待手机扫描完整个ＳＤ卡，这个过程大概30分钟。至于扫描是否完成，你可以看TAG为MediaProvider的日志。 第三步 ：拔出外部SD卡，再次等手机进行扫描大概10分钟。 第四步 ：按下手机的电源key +音量down key来截屏。 第五步 ：通过电脑查看内部SD卡的DCIM\.thumbnails\.thumbdata4--1967290299文件。这时你会发现，该文件多达1G. 对于该问题，大概的逻辑是这样的： MediaProvider会对SD卡上的文件的进行扫描，得到一些基本的信息放入数据库的files这个表中。 对于一些图片（比如手机截屏图片），手机会以这些图片文件在files表中的_id的值，作为一个定位标志，把其缩略文件存放在.thumbdata4--1967290299中。 比如 ：_id为1，那么该文件的缩略图就存放在.thumbdata4--1967290299文件的_id * BYTES_PER_MINTHUMB开始的位置，其中BYTES_PER_MINTHUMB = 17000， 对此可以参照MiniThumbFile.java文件中的 saveMiniThumbToFile(byte[] data, long id, long magic)等函数 对于Android的Sqlite3数据库，_id是自增的。比如，最开始我插入了10001记录，这时最后一条记录的_id为10001,这时如果删除1到10000条记录， 再插入一条记录，那么这条的记录的_id值为10002. 因此， 随着用户日常中不停的向SD卡反复地添加删除文件，那么files表中的_id的值会不停的增大， 当该值为10万时，即使我们截屏时，系统只把该截屏图片这样一张图的缩略图保存在.thumbdata4--1967290299文件， 10万*BYTES_PER_MINTHUMB>1G,也就是说.thumbdata4--1967290299文件就会占用了1G多的SD空间。随着时间的推移，该值会继续变大，直到填满SD卡。 我们的方案就是把 .thumbdata4--1967290299 文件分成多个文件来存储缩略图。 比如.thumbdata4--1967290299-0存_id 为1到1024的文件的缩略图，.thumbdata4--1967290299-1存_id 为1025到2048的文件的缩略图 同时对缩略图文件做一些维护，即如果一个缩略图文件本身对应原文件不在时，清理掉该微缩略图文件。 另外在极端情况下（剩余容量小于100M下），清理掉所有的微缩略图文件。 在MTK 6575平台上对该问题的修改包含2个文件的修改：<div><span class="pln"><span class="pln"> modified</span></span><span class="pun" style="color:#0;"><span class="pun">:</span></span><span class="pln"><span class="pln"> frameworks</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="kwd" style="color:#0;"><span class="kwd">base</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">media</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">java</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">android</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">media</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="typ" style="color:#0;"><span class="typ">MediaScanner</span></span><span class="pun" style="color:#0;"><span class="pun">.</span></span><span class="pln"><span class="pln">java</span></span></div><div><span class="pln"><span class="pln"> modified</span></span><span class="pun" style="color:#0;"><span class="pun">:</span></span><span class="pln"><span class="pln"> frameworks</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="kwd" style="color:#0;"><span class="kwd">base</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">media</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">java</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">android</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="pln"><span class="pln">media</span></span><span class="pun" style="color:#0;"><span class="pun">/</span></span><span class="typ" style="color:#0;"><span class="typ">MiniThumbFile</span></span><span class="pun" style="color:#0;"><span class="pun">.</span></span><span class="pln"><span class="pln">java</span></span></div>MiniThumbFile.java文件的主要修改如下：
<div class="dp-highlighter bg_java" sizcache="27" sizset="60"><div class="bar" sizcache="27" sizset="60"><div class="tools" sizcache="27" sizset="60"><strong>[java]</strong> <a target=_blank title="view plain" class="ViewSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">view plain</a><a target=_blank title="copy" class="CopyToClipboard" href="http://blog.csdn.net/fengye810130/article/details/9118221#">copy</a><a target=_blank title="print" class="PrintSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">print</a><a target=_blank title="?" class="About" href="http://blog.csdn.net/fengye810130/article/details/9118221#">?</a></div></div><ol class="dp-j"><li class="alt"><span><span><PRE</span><span class="keyword">class</span><span>=javaname=</span><span class="string">"code"</span><span>></span><span class="comment">/**</span></span></li><li><span><span class="comment">@@-85,16+89,34@@publicclassMiniThumbFile{</span></span></li><li class="alt"><span><span class="comment">/*add1ongoogle'sversion.*/</span><span></span></span></li><li><span></span><span class="comment">/*thisversionaddcheckcodeforthumbdata.*/</span><span></span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>MINI_THUMB_DATA_FILE_VERSION=</span><span class="number">3</span><span>+</span><span class="number">1</span><span>;</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>BYTES_PER_MINTHUMB=</span><span class="number">17000</span><span>;</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>BYTES_PER_MINTHUMB=</span><span class="number">17000</span><span>;</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>HEADER_SIZE=</span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>;</span></li><li class="alt"><span></span><span class="keyword">private</span><span>UrimUri;</span></li><li><span></span><span class="keyword">private</span><span>RandomAccessFilemMiniThumbFile;</span></li><li class="alt"><span>Map<Long,RandomAccessFile>mMiniThumbFilesMap=Collections.synchronizedMap(</span><span class="keyword">new</span><span>HashMap<Long,RandomAccessFile>(</span><span class="number">5</span><span>));</span></li><li><span></span><span class="keyword">private</span><span>FileChannelmChannel;</span></li><li class="alt"><span></span><span class="keyword">private</span><span>ByteBuffermBuffer;</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span>Hashtable<String,MiniThumbFile>sThumbFiles=</span></li><li class="alt"><span></span><span class="keyword">new</span><span>Hashtable<String,MiniThumbFile>();</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span>java.util.zip.Adler32sChecker=</span><span class="keyword">new</span><span>Adler32();</span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>UNKNOWN_CHECK_CODE=-</span><span class="number">1</span><span>;</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">static</span><span></span><span class="keyword">char</span><span>SEPERATE_CHAR=</span><span class="string">'_'</span><span>;</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span>String[]parseFileName(StringfileName)</span></li><li><span>{</span></li><li class="alt"><span>Stringstr=fileName;</span></li><li><span></span><span class="keyword">if</span><span>(fileName==</span><span class="keyword">null</span><span>)</span></li><li class="alt"><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li><span></span><span class="keyword">int</span><span>index=fileName.lastIndexOf(</span><span class="string">"/"</span><span>);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(index!=-</span><span class="number">1</span><span>)</span></li><li><span>{</span></li><li class="alt"><span>str=fileName.substring(index+</span><span class="number">1</span><span>);</span></li><li><span>}</span></li><li class="alt"><span>Stringstrs[]=str.split(SEPERATE_CHAR+</span><span class="string">""</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(strs==</span><span class="keyword">null</span><span>||strs.length!=</span><span class="number">4</span><span>||(!str.startsWith(</span><span class="string">".thumbdata"</span><span>)))</span></li><li class="alt"><span>{</span></li><li><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">return</span><span>strs;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="comment">/**</span></li><li class="alt"><span><span class="comment">*Westoredifferenttypesofthumbnailsindifferentfiles.Toremainbackwardcompatibility,</span></span></li><li><span><span class="comment">*weshouldhashcodeofcontent://media/external/images/mediaremainsthesame.</span></span></li><li class="alt"><span><span class="comment">@@-105,7+127,18@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">sThumbFiles.clear();</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment"></span></span></li><li><span><span class="comment">privatefinalstaticlonggetMiniThumbFileId(longid)</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(id>>8);</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">publicfinalstaticintgetMiniThumbDataFileBlockNum()</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(1<<8);</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">privatefinalstaticlonggetPositionInMiniThumbFile(longid)</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(id&0xff)*BYTES_PER_MINTHUMB;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">publicstaticsynchronizedMiniThumbFileinstance(Uriuri){</span></span></li><li class="alt"><span><span class="comment">Stringtype=uri.getPathSegments().get(1);</span></span></li><li><span><span class="comment">MiniThumbFilefile=sThumbFiles.get(type);</span></span></li><li class="alt"><span><span class="comment">@@-120,10+153,11@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">privateStringrandomAccessFilePath(intversion){</span></span></li><li><span><span class="comment">Stringtype=mUri.getPathSegments().get(1);</span></span></li><li class="alt"><span><span class="comment">StringdirectoryName=</span></span></li><li><span><span class="comment">Environment.getExternalStorageDirectory().toString()+"/DCIM/.thumbnails";</span></span></li><li class="alt"><span><span class="comment">returndirectoryName+"/.thumbdata"+version+"-"+mUri.hashCode();</span></span></li><li><span><span class="comment">returndirectoryName+"/.thumbdata"+version+SEPERATE_CHAR+mUri.hashCode()+SEPERATE_CHAR+type;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">/**</span></span></li><li class="alt"><span><span class="comment">@@-131,18+165,18@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">*@paramuritheUrisameasinstance(Uriuri).</span></span></li><li class="alt"><span><span class="comment">*@return</span></span></li><li><span><span class="comment">*/</span><span></span></span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span>StringgetThumbdataPath(Uriuri){</span></li><li><span></span><span class="comment">/*publicstaticStringgetThumbdataPath(Uriuri){</span></li><li class="alt"><span><span class="comment">Stringtype=uri.getPathSegments().get(1);</span></span></li><li><span><span class="comment">UrithumbFileUri=Uri.parse("content://media/external/"+type+"/media");</span></span></li><li class="alt"><span><span class="comment">StringdirectoryName=Environment.getExternalStorageDirectory().toString()</span></span></li><li><span><span class="comment">+"/DCIM/.thumbnails";</span></span></li><li class="alt"><span><span class="comment">Stringpath=directoryName+"/.thumbdata"+MINI_THUMB_DATA_FILE_VERSION+"-"+thumbFileUri.hashCode();</span></span></li><li><span><span class="comment">Stringpath=directoryName+"/.thumbdata"+MINI_THUMB_DATA_FILE_VERSION+SEPERATE_CHAR+thumbFileUri.hashCode()+SEPERATE_CHAR+type;</span></span></li><li class="alt"><span><span class="comment">if(LOG)Log.i(TAG,"getThumbdataPath("+uri+")return"+path);</span></span></li><li><span><span class="comment">returnpath;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">}*/</span><span></span></span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>removeOldFile(){</span></li><li><span>StringoldPath=randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION-</span><span class="number">1</span><span>);</span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>removeOldMiniThumbDataFile(</span><span class="keyword">long</span><span>miniThumbDataFileId){</span></li><li><span>StringoldPath=getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION-</span><span class="number">1</span><span>,miniThumbDataFileId);</span></li><li class="alt"><span>FileoldFile=</span><span class="keyword">new</span><span>File(oldPath);</span></li><li><span></span><span class="keyword">if</span><span>(oldFile.exists()){</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>@@-</span><span class="number">152</span><span>,</span><span class="number">35</span><span>+</span><span class="number">186</span><span>,</span><span class="number">43</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(){</span></li><li><span></span><span class="keyword">if</span><span>(mMiniThumbFile==</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>removeOldFile();</span></li><li><span>Stringpath=randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION);</span></li><li class="alt"><span>Filedirectory=</span><span class="keyword">new</span><span>File(path).getParentFile();</span></li><li><span></span><span class="keyword">if</span><span>(!directory.isDirectory()){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(!directory.mkdirs()){</span></li><li><span>Log.e(TAG,</span><span class="string">"Unabletocreate.thumbnailsdirectory"</span><span></span></li><li class="alt"><span>+directory.toString());</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">private</span><span>StringgetMiniThumbDataFilePath(</span><span class="keyword">int</span><span>version,</span><span class="keyword">long</span><span>miniThumbDataFileId)</span></li><li class="alt"><span>{</span></li><li><span></span><span class="keyword">return</span><span>randomAccessFilePath(version)+SEPERATE_CHAR+miniThumbDataFileId;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(</span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId){</span></li><li class="alt"><span></span><span class="keyword">return</span><span>miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">false</span><span>);</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(</span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId,</span><span class="keyword">boolean</span><span>onlyRead){</span></li><li><span>RandomAccessFileminiThumbFile=mMiniThumbFilesMap.get(miniThumbDataFileId);</span></li><li class="alt"><span>Stringpath=getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION,miniThumbDataFileId);</span></li><li><span>Filef=</span><span class="keyword">new</span><span>File(path);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(miniThumbFile==</span><span class="keyword">null</span><span>||!f.exists()){</span></li><li><span></span><span class="keyword">if</span><span>(onlyRead)</span></li><li class="alt"><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li><span>removeOldMiniThumbDataFile(miniThumbDataFileId);</span></li><li class="alt"><span>Filedirectory=</span><span class="keyword">new</span><span>File(path).getParentFile();</span></li><li><span></span><span class="keyword">if</span><span>(!directory.isDirectory()){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(!directory.mkdirs()){</span></li><li><span>Log.e(TAG,</span><span class="string">"Unabletocreate.thumbnailsdirectory"</span><span></span></li><li class="alt"><span>+directory.toString());</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mMiniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"rw"</span><span>);</span></li><li class="alt"><span>miniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"rw"</span><span>);</span></li><li><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li class="alt"><span></span><span class="comment">//Openasread-onlysowecanatleastreadtheexisting </span><span></span></li><li><span></span><span class="comment">//thumbnails. </span><span></span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mMiniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"r"</span><span>);</span></li><li class="alt"><span>miniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"r"</span><span>);</span></li><li><span>}</span><span class="keyword">catch</span><span>(IOExceptionex2){</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mMiniThumbFile!=</span><span class="keyword">null</span><span>){</span></li><li><span>mChannel=mMiniThumbFile.getChannel();</span></li><li class="alt"><span>}</span></li><li><span>mMiniThumbFilesMap.put(miniThumbDataFileId,miniThumbFile);</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">return</span><span>mMiniThumbFile;</span></li><li class="alt"><span></span><span class="keyword">return</span><span>miniThumbFile;</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">public</span><span>MiniThumbFile(Uriuri){</span></li><li><span>@@-</span><span class="number">189</span><span>,</span><span class="number">10</span><span>+</span><span class="number">231</span><span>,</span><span class="number">19</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">void</span><span>deactivate(){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mMiniThumbFile!=</span><span class="keyword">null</span><span>){</span></li><li><span></span><span class="keyword">if</span><span>(mMiniThumbFilesMap!=</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>Set<Long>keySet=mMiniThumbFilesMap.keySet();</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>mMiniThumbFile.close();</span></li><li><span>mMiniThumbFile=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">for</span><span>(Longkey:keySet)</span></li><li><span>{</span></li><li class="alt"><span>RandomAccessFilefile=mMiniThumbFilesMap.get(key);</span></li><li><span></span><span class="keyword">if</span><span>(file!=</span><span class="keyword">null</span><span>)</span></li><li class="alt"><span>{</span></li><li><span>mMiniThumbFilesMap.put(key,</span><span class="keyword">null</span><span>);</span></li><li class="alt"><span>file.close();</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span>mMiniThumbFilesMap.clear();</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li><span></span><span class="comment">//ignoreexception </span><span></span></li><li class="alt"><span>}</span></li><li><span>@@-</span><span class="number">205</span><span>,</span><span class="number">18</span><span>+</span><span class="number">256</span><span>,</span><span class="number">20</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span></span><span class="comment">//checktheminithumbfilefortherightdata.Rightis </span><span></span></li><li><span></span><span class="comment">//definedashavingtherightmagicnumberattheoffset </span><span></span></li><li class="alt"><span></span><span class="comment">//reservedforthis"id". </span><span></span></li><li><span>RandomAccessFiler=miniThumbDataFile();</span></li><li class="alt"><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">true</span><span>);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(r!=</span><span class="keyword">null</span><span>){</span></li><li><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>mBuffer.clear();</span></li><li><span>mBuffer.limit(</span><span class="number">1</span><span>+</span><span class="number">8</span><span>);</span></li><li class="alt"><span>lock=mChannel.lock(pos,</span><span class="number">1</span><span>+</span><span class="number">8</span><span>,</span><span class="keyword">true</span><span>);</span></li><li><span>lock=channel.lock(pos,</span><span class="number">1</span><span>+</span><span class="number">8</span><span>,</span><span class="keyword">true</span><span>);</span></li><li class="alt"><span></span><span class="comment">//checkthatwecanreadthefollowing9bytes </span><span></span></li><li><span></span><span class="comment">//(1forthe"status"and8forthelong) </span><span></span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mChannel.read(mBuffer,pos)==</span><span class="number">9</span><span>){</span></li><li><span></span><span class="keyword">if</span><span>(channel.read(mBuffer,pos)==</span><span class="number">9</span><span>){</span></li><li class="alt"><span>mBuffer.position(</span><span class="number">0</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(mBuffer.get()==</span><span class="number">1</span><span>){</span></li><li class="alt"><span></span><span class="keyword">return</span><span>mBuffer.getLong();</span></li><li><span>@@-</span><span class="number">242</span><span>,</span><span class="number">10</span><span>+</span><span class="number">295</span><span>,</span><span class="number">12</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">void</span><span>saveMiniThumbToFile(</span><span class="keyword">byte</span><span>[]data,</span><span class="keyword">long</span><span>id,</span><span class="keyword">long</span><span>magic)</span></li><li><span></span><span class="keyword">throws</span><span>IOException{</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile();</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId);</span></li><li><span></span><span class="keyword">if</span><span>(r==</span><span class="keyword">null</span><span>)</span><span class="keyword">return</span><span>;</span></li><li class="alt"><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span></span><span class="keyword">if</span><span>(data!=</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>@@-</span><span class="number">266</span><span>,</span><span class="number">14</span><span>+</span><span class="number">321</span><span>,</span><span class="number">13</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li><span>check=sChecker.getValue();</span></li><li class="alt"><span>}</span></li><li><span>mBuffer.putLong(check);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"saveMiniThumbToFile("</span><span>+id+</span><span class="string">")flag=1,magic="</span><span></span></li><li><span>+magic+</span><span class="string">",length="</span><span>+data.length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span></li><li><span>mBuffer.put(data);</span></li><li class="alt"><span>mBuffer.flip();</span></li><li><span>lock=mChannel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">false</span><span>);</span></li><li class="alt"><span>mChannel.write(mBuffer,pos);</span></li><li><span>lock=channel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">false</span><span>);</span></li><li class="alt"><span>channel.write(mBuffer,pos);</span></li><li><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"saveMiniThumbToFile("</span><span>+id+</span><span class="string">")flag=1,magic="</span><span></span></li><li class="alt"><span>+magic+</span><span class="string">",length="</span><span>+data.length+</span><span class="string">",check="</span><span>+check);</span></li><li><span>}</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li><span>Log.e(TAG,</span><span class="string">"couldn'tsaveminithumbnaildatafor"</span><span></span></li><li class="alt"><span>@@-</span><span class="number">319</span><span>,</span><span class="number">27</span><span>+</span><span class="number">373</span><span>,</span><span class="number">29</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li><span>*</span><span class="annotation">@return</span><span></span></li><li class="alt"><span>*/</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">byte</span><span>[]getMiniThumbFromFile(</span><span class="keyword">long</span><span>id,</span><span class="keyword">byte</span><span>[]data,ThumbResultresult){</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile();</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(r==</span><span class="keyword">null</span><span>)</span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mBuffer.clear();</span></li><li class="alt"><span>lock=mChannel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">int</span><span>size=mChannel.read(mBuffer,pos);</span></li><li class="alt"><span>lock=channel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">int</span><span>size=channel.read(mBuffer,pos);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(size></span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>){</span><span class="comment">//flag,magic,length,checkcode </span><span></span></li><li><span>mBuffer.position(</span><span class="number">0</span><span>);</span></li><li class="alt"><span></span><span class="keyword">byte</span><span>flag=mBuffer.get();</span></li><li><span></span><span class="keyword">long</span><span>magic=mBuffer.getLong();</span></li><li class="alt"><span></span><span class="keyword">int</span><span>length=mBuffer.getInt();</span></li><li><span></span><span class="keyword">long</span><span>check=mBuffer.getLong();</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"getMiniThumbFromFile("</span><span>+id+</span><span class="string">")flag="</span><span>+flag</span></li><li><span>+</span><span class="string">",magic="</span><span>+magic+</span><span class="string">",length="</span><span>+length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span></li><li><span></span><span class="keyword">long</span><span>newCheck=UNKNOWN_CHECK_CODE;</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(size>=</span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>+length&&data.length>=length){</span></li><li><span>mBuffer.get(data,</span><span class="number">0</span><span>,length);</span></li><li class="alt"><span>Log.i(TAG,</span><span class="string">"successtogetMiniThumbFromFile("</span><span>+id+</span><span class="string">")flag="</span><span>+flag</span></li><li><span>+</span><span class="string">",magic="</span><span>+magic+</span><span class="string">",length="</span><span>+length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span><span class="keyword">synchronized</span><span>(sChecker){</span></li><li><span>sChecker.reset();</span></li><li class="alt"><span>sChecker.update(data,</span><span class="number">0</span><span>,length);</PRE><BR></span></li></ol></div><pre class="java" style="DISPLAY: none" sizcache="27" sizset="64" name="code"><div class="dp-highlighter bg_java" sizcache="27" sizset="64"><div class="bar" sizcache="27" sizset="64"><div class="tools" sizcache="27" sizset="64"><strong>[java]</strong> <a target=_blank title="view plain" class="ViewSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">view plain</a><a target=_blank title="copy" class="CopyToClipboard" href="http://blog.csdn.net/fengye810130/article/details/9118221#">copy</a><a target=_blank title="print" class="PrintSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">print</a><a target=_blank title="?" class="About" href="http://blog.csdn.net/fengye810130/article/details/9118221#">?</a></div></div><ol class="dp-j"><li class="alt"><span><span class="comment">/**</span></span></li><li><span><span class="comment">@@-85,16+89,34@@publicclassMiniThumbFile{</span></span></li><li class="alt"><span><span class="comment">/*add1ongoogle'sversion.*/</span><span></span></span></li><li><span></span><span class="comment">/*thisversionaddcheckcodeforthumbdata.*/</span><span></span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>MINI_THUMB_DATA_FILE_VERSION=</span><span class="number">3</span><span>+</span><span class="number">1</span><span>;</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>BYTES_PER_MINTHUMB=</span><span class="number">17000</span><span>;</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>BYTES_PER_MINTHUMB=</span><span class="number">17000</span><span>;</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">int</span><span>HEADER_SIZE=</span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>;</span></li><li class="alt"><span></span><span class="keyword">private</span><span>UrimUri;</span></li><li><span></span><span class="keyword">private</span><span>RandomAccessFilemMiniThumbFile;</span></li><li class="alt"><span>Map<Long,RandomAccessFile>mMiniThumbFilesMap=Collections.synchronizedMap(</span><span class="keyword">new</span><span>HashMap<Long,RandomAccessFile>(</span><span class="number">5</span><span>));</span></li><li><span></span><span class="keyword">private</span><span>FileChannelmChannel;</span></li><li class="alt"><span></span><span class="keyword">private</span><span>ByteBuffermBuffer;</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span>Hashtable<String,MiniThumbFile>sThumbFiles=</span></li><li class="alt"><span></span><span class="keyword">new</span><span>Hashtable<String,MiniThumbFile>();</span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span>java.util.zip.Adler32sChecker=</span><span class="keyword">new</span><span>Adler32();</span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">static</span><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>UNKNOWN_CHECK_CODE=-</span><span class="number">1</span><span>;</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">static</span><span></span><span class="keyword">char</span><span>SEPERATE_CHAR=</span><span class="string">'_'</span><span>;</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span>String[]parseFileName(StringfileName)</span></li><li><span>{</span></li><li class="alt"><span>Stringstr=fileName;</span></li><li><span></span><span class="keyword">if</span><span>(fileName==</span><span class="keyword">null</span><span>)</span></li><li class="alt"><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li><span></span><span class="keyword">int</span><span>index=fileName.lastIndexOf(</span><span class="string">"/"</span><span>);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(index!=-</span><span class="number">1</span><span>)</span></li><li><span>{</span></li><li class="alt"><span>str=fileName.substring(index+</span><span class="number">1</span><span>);</span></li><li><span>}</span></li><li class="alt"><span>Stringstrs[]=str.split(SEPERATE_CHAR+</span><span class="string">""</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(strs==</span><span class="keyword">null</span><span>||strs.length!=</span><span class="number">4</span><span>||(!str.startsWith(</span><span class="string">".thumbdata"</span><span>)))</span></li><li class="alt"><span>{</span></li><li><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">return</span><span>strs;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="comment">/**</span></li><li class="alt"><span><span class="comment">*Westoredifferenttypesofthumbnailsindifferentfiles.Toremainbackwardcompatibility,</span></span></li><li><span><span class="comment">*weshouldhashcodeofcontent://media/external/images/mediaremainsthesame.</span></span></li><li class="alt"><span><span class="comment">@@-105,7+127,18@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">sThumbFiles.clear();</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment"></span></span></li><li><span><span class="comment">privatefinalstaticlonggetMiniThumbFileId(longid)</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(id>>8);</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">publicfinalstaticintgetMiniThumbDataFileBlockNum()</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(1<<8);</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">privatefinalstaticlonggetPositionInMiniThumbFile(longid)</span></span></li><li class="alt"><span><span class="comment">{</span></span></li><li><span><span class="comment">return(id&0xff)*BYTES_PER_MINTHUMB;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">publicstaticsynchronizedMiniThumbFileinstance(Uriuri){</span></span></li><li class="alt"><span><span class="comment">Stringtype=uri.getPathSegments().get(1);</span></span></li><li><span><span class="comment">MiniThumbFilefile=sThumbFiles.get(type);</span></span></li><li class="alt"><span><span class="comment">@@-120,10+153,11@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">privateStringrandomAccessFilePath(intversion){</span></span></li><li><span><span class="comment">Stringtype=mUri.getPathSegments().get(1);</span></span></li><li class="alt"><span><span class="comment">StringdirectoryName=</span></span></li><li><span><span class="comment">Environment.getExternalStorageDirectory().toString()+"/DCIM/.thumbnails";</span></span></li><li class="alt"><span><span class="comment">returndirectoryName+"/.thumbdata"+version+"-"+mUri.hashCode();</span></span></li><li><span><span class="comment">returndirectoryName+"/.thumbdata"+version+SEPERATE_CHAR+mUri.hashCode()+SEPERATE_CHAR+type;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">/**</span></span></li><li class="alt"><span><span class="comment">@@-131,18+165,18@@publicclassMiniThumbFile{</span></span></li><li><span><span class="comment">*@paramuritheUrisameasinstance(Uriuri).</span></span></li><li class="alt"><span><span class="comment">*@return</span></span></li><li><span><span class="comment">*/</span><span></span></span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">static</span><span>StringgetThumbdataPath(Uriuri){</span></li><li><span></span><span class="comment">/*publicstaticStringgetThumbdataPath(Uriuri){</span></li><li class="alt"><span><span class="comment">Stringtype=uri.getPathSegments().get(1);</span></span></li><li><span><span class="comment">UrithumbFileUri=Uri.parse("content://media/external/"+type+"/media");</span></span></li><li class="alt"><span><span class="comment">StringdirectoryName=Environment.getExternalStorageDirectory().toString()</span></span></li><li><span><span class="comment">+"/DCIM/.thumbnails";</span></span></li><li class="alt"><span><span class="comment">Stringpath=directoryName+"/.thumbdata"+MINI_THUMB_DATA_FILE_VERSION+"-"+thumbFileUri.hashCode();</span></span></li><li><span><span class="comment">Stringpath=directoryName+"/.thumbdata"+MINI_THUMB_DATA_FILE_VERSION+SEPERATE_CHAR+thumbFileUri.hashCode()+SEPERATE_CHAR+type;</span></span></li><li class="alt"><span><span class="comment">if(LOG)Log.i(TAG,"getThumbdataPath("+uri+")return"+path);</span></span></li><li><span><span class="comment">returnpath;</span></span></li><li class="alt"><span><span class="comment">}</span></span></li><li><span><span class="comment">}*/</span><span></span></span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>removeOldFile(){</span></li><li><span>StringoldPath=randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION-</span><span class="number">1</span><span>);</span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>removeOldMiniThumbDataFile(</span><span class="keyword">long</span><span>miniThumbDataFileId){</span></li><li><span>StringoldPath=getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION-</span><span class="number">1</span><span>,miniThumbDataFileId);</span></li><li class="alt"><span>FileoldFile=</span><span class="keyword">new</span><span>File(oldPath);</span></li><li><span></span><span class="keyword">if</span><span>(oldFile.exists()){</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>@@-</span><span class="number">152</span><span>,</span><span class="number">35</span><span>+</span><span class="number">186</span><span>,</span><span class="number">43</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(){</span></li><li><span></span><span class="keyword">if</span><span>(mMiniThumbFile==</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>removeOldFile();</span></li><li><span>Stringpath=randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION);</span></li><li class="alt"><span>Filedirectory=</span><span class="keyword">new</span><span>File(path).getParentFile();</span></li><li><span></span><span class="keyword">if</span><span>(!directory.isDirectory()){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(!directory.mkdirs()){</span></li><li><span>Log.e(TAG,</span><span class="string">"Unabletocreate.thumbnailsdirectory"</span><span></span></li><li class="alt"><span>+directory.toString());</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">private</span><span>StringgetMiniThumbDataFilePath(</span><span class="keyword">int</span><span>version,</span><span class="keyword">long</span><span>miniThumbDataFileId)</span></li><li class="alt"><span>{</span></li><li><span></span><span class="keyword">return</span><span>randomAccessFilePath(version)+SEPERATE_CHAR+miniThumbDataFileId;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(</span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId){</span></li><li class="alt"><span></span><span class="keyword">return</span><span>miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">false</span><span>);</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">private</span><span>RandomAccessFileminiThumbDataFile(</span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId,</span><span class="keyword">boolean</span><span>onlyRead){</span></li><li><span>RandomAccessFileminiThumbFile=mMiniThumbFilesMap.get(miniThumbDataFileId);</span></li><li class="alt"><span>Stringpath=getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION,miniThumbDataFileId);</span></li><li><span>Filef=</span><span class="keyword">new</span><span>File(path);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(miniThumbFile==</span><span class="keyword">null</span><span>||!f.exists()){</span></li><li><span></span><span class="keyword">if</span><span>(onlyRead)</span></li><li class="alt"><span></span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li><span>removeOldMiniThumbDataFile(miniThumbDataFileId);</span></li><li class="alt"><span>Filedirectory=</span><span class="keyword">new</span><span>File(path).getParentFile();</span></li><li><span></span><span class="keyword">if</span><span>(!directory.isDirectory()){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(!directory.mkdirs()){</span></li><li><span>Log.e(TAG,</span><span class="string">"Unabletocreate.thumbnailsdirectory"</span><span></span></li><li class="alt"><span>+directory.toString());</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mMiniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"rw"</span><span>);</span></li><li class="alt"><span>miniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"rw"</span><span>);</span></li><li><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li class="alt"><span></span><span class="comment">//Openasread-onlysowecanatleastreadtheexisting </span><span></span></li><li><span></span><span class="comment">//thumbnails. </span><span></span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mMiniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"r"</span><span>);</span></li><li class="alt"><span>miniThumbFile=</span><span class="keyword">new</span><span>RandomAccessFile(f,</span><span class="string">"r"</span><span>);</span></li><li><span>}</span><span class="keyword">catch</span><span>(IOExceptionex2){</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mMiniThumbFile!=</span><span class="keyword">null</span><span>){</span></li><li><span>mChannel=mMiniThumbFile.getChannel();</span></li><li class="alt"><span>}</span></li><li><span>mMiniThumbFilesMap.put(miniThumbDataFileId,miniThumbFile);</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">return</span><span>mMiniThumbFile;</span></li><li class="alt"><span></span><span class="keyword">return</span><span>miniThumbFile;</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">public</span><span>MiniThumbFile(Uriuri){</span></li><li><span>@@-</span><span class="number">189</span><span>,</span><span class="number">10</span><span>+</span><span class="number">231</span><span>,</span><span class="number">19</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">void</span><span>deactivate(){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mMiniThumbFile!=</span><span class="keyword">null</span><span>){</span></li><li><span></span><span class="keyword">if</span><span>(mMiniThumbFilesMap!=</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>Set<Long>keySet=mMiniThumbFilesMap.keySet();</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>mMiniThumbFile.close();</span></li><li><span>mMiniThumbFile=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">for</span><span>(Longkey:keySet)</span></li><li><span>{</span></li><li class="alt"><span>RandomAccessFilefile=mMiniThumbFilesMap.get(key);</span></li><li><span></span><span class="keyword">if</span><span>(file!=</span><span class="keyword">null</span><span>)</span></li><li class="alt"><span>{</span></li><li><span>mMiniThumbFilesMap.put(key,</span><span class="keyword">null</span><span>);</span></li><li class="alt"><span>file.close();</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span>mMiniThumbFilesMap.clear();</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li><span></span><span class="comment">//ignoreexception </span><span></span></li><li class="alt"><span>}</span></li><li><span>@@-</span><span class="number">205</span><span>,</span><span class="number">18</span><span>+</span><span class="number">256</span><span>,</span><span class="number">20</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span></span><span class="comment">//checktheminithumbfilefortherightdata.Rightis </span><span></span></li><li><span></span><span class="comment">//definedashavingtherightmagicnumberattheoffset </span><span></span></li><li class="alt"><span></span><span class="comment">//reservedforthis"id". </span><span></span></li><li><span>RandomAccessFiler=miniThumbDataFile();</span></li><li class="alt"><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">true</span><span>);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(r!=</span><span class="keyword">null</span><span>){</span></li><li><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>mBuffer.clear();</span></li><li><span>mBuffer.limit(</span><span class="number">1</span><span>+</span><span class="number">8</span><span>);</span></li><li class="alt"><span>lock=mChannel.lock(pos,</span><span class="number">1</span><span>+</span><span class="number">8</span><span>,</span><span class="keyword">true</span><span>);</span></li><li><span>lock=channel.lock(pos,</span><span class="number">1</span><span>+</span><span class="number">8</span><span>,</span><span class="keyword">true</span><span>);</span></li><li class="alt"><span></span><span class="comment">//checkthatwecanreadthefollowing9bytes </span><span></span></li><li><span></span><span class="comment">//(1forthe"status"and8forthelong) </span><span></span></li><li class="alt"><span></span><span class="keyword">if</span><span>(mChannel.read(mBuffer,pos)==</span><span class="number">9</span><span>){</span></li><li><span></span><span class="keyword">if</span><span>(channel.read(mBuffer,pos)==</span><span class="number">9</span><span>){</span></li><li class="alt"><span>mBuffer.position(</span><span class="number">0</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(mBuffer.get()==</span><span class="number">1</span><span>){</span></li><li class="alt"><span></span><span class="keyword">return</span><span>mBuffer.getLong();</span></li><li><span>@@-</span><span class="number">242</span><span>,</span><span class="number">10</span><span>+</span><span class="number">295</span><span>,</span><span class="number">12</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li class="alt"><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">void</span><span>saveMiniThumbToFile(</span><span class="keyword">byte</span><span>[]data,</span><span class="keyword">long</span><span>id,</span><span class="keyword">long</span><span>magic)</span></li><li><span></span><span class="keyword">throws</span><span>IOException{</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile();</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId);</span></li><li><span></span><span class="keyword">if</span><span>(r==</span><span class="keyword">null</span><span>)</span><span class="keyword">return</span><span>;</span></li><li class="alt"><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span></span><span class="keyword">if</span><span>(data!=</span><span class="keyword">null</span><span>){</span></li><li class="alt"><span>@@-</span><span class="number">266</span><span>,</span><span class="number">14</span><span>+</span><span class="number">321</span><span>,</span><span class="number">13</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li><span>check=sChecker.getValue();</span></li><li class="alt"><span>}</span></li><li><span>mBuffer.putLong(check);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"saveMiniThumbToFile("</span><span>+id+</span><span class="string">")flag=1,magic="</span><span></span></li><li><span>+magic+</span><span class="string">",length="</span><span>+data.length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span></li><li><span>mBuffer.put(data);</span></li><li class="alt"><span>mBuffer.flip();</span></li><li><span>lock=mChannel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">false</span><span>);</span></li><li class="alt"><span>mChannel.write(mBuffer,pos);</span></li><li><span>lock=channel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">false</span><span>);</span></li><li class="alt"><span>channel.write(mBuffer,pos);</span></li><li><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"saveMiniThumbToFile("</span><span>+id+</span><span class="string">")flag=1,magic="</span><span></span></li><li class="alt"><span>+magic+</span><span class="string">",length="</span><span>+data.length+</span><span class="string">",check="</span><span>+check);</span></li><li><span>}</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(IOExceptionex){</span></li><li><span>Log.e(TAG,</span><span class="string">"couldn'tsaveminithumbnaildatafor"</span><span></span></li><li class="alt"><span>@@-</span><span class="number">319</span><span>,</span><span class="number">27</span><span>+</span><span class="number">373</span><span>,</span><span class="number">29</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MiniThumbFile{</span></li><li><span>*</span><span class="annotation">@return</span><span></span></li><li class="alt"><span>*/</span></li><li><span></span><span class="keyword">public</span><span></span><span class="keyword">synchronized</span><span></span><span class="keyword">byte</span><span>[]getMiniThumbFromFile(</span><span class="keyword">long</span><span>id,</span><span class="keyword">byte</span><span>[]data,ThumbResultresult){</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile();</span></li><li><span></span><span class="keyword">final</span><span></span><span class="keyword">long</span><span>miniThumbDataFileId=getMiniThumbFileId(id);</span></li><li class="alt"><span>RandomAccessFiler=miniThumbDataFile(miniThumbDataFileId,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(r==</span><span class="keyword">null</span><span>)</span><span class="keyword">return</span><span></span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">long</span><span>pos=id*BYTES_PER_MINTHUMB;</span></li><li><span></span><span class="keyword">long</span><span>pos=getPositionInMiniThumbFile(id);</span></li><li class="alt"><span>FileChannelchannel=r.getChannel();</span></li><li><span>FileLocklock=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>mBuffer.clear();</span></li><li class="alt"><span>lock=mChannel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">int</span><span>size=mChannel.read(mBuffer,pos);</span></li><li class="alt"><span>lock=channel.lock(pos,BYTES_PER_MINTHUMB,</span><span class="keyword">true</span><span>);</span></li><li><span></span><span class="keyword">int</span><span>size=channel.read(mBuffer,pos);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(size></span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>){</span><span class="comment">//flag,magic,length,checkcode </span><span></span></li><li><span>mBuffer.position(</span><span class="number">0</span><span>);</span></li><li class="alt"><span></span><span class="keyword">byte</span><span>flag=mBuffer.get();</span></li><li><span></span><span class="keyword">long</span><span>magic=mBuffer.getLong();</span></li><li class="alt"><span></span><span class="keyword">int</span><span>length=mBuffer.getInt();</span></li><li><span></span><span class="keyword">long</span><span>check=mBuffer.getLong();</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)Log.i(TAG,</span><span class="string">"getMiniThumbFromFile("</span><span>+id+</span><span class="string">")flag="</span><span>+flag</span></li><li><span>+</span><span class="string">",magic="</span><span>+magic+</span><span class="string">",length="</span><span>+length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span></li><li><span></span><span class="keyword">long</span><span>newCheck=UNKNOWN_CHECK_CODE;</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(size>=</span><span class="number">1</span><span>+</span><span class="number">8</span><span>+</span><span class="number">4</span><span>+</span><span class="number">8</span><span>+length&&data.length>=length){</span></li><li><span>mBuffer.get(data,</span><span class="number">0</span><span>,length);</span></li><li class="alt"><span>Log.i(TAG,</span><span class="string">"successtogetMiniThumbFromFile("</span><span>+id+</span><span class="string">")flag="</span><span>+flag</span></li><li><span>+</span><span class="string">",magic="</span><span>+magic+</span><span class="string">",length="</span><span>+length+</span><span class="string">",check="</span><span>+check);</span></li><li class="alt"><span></span><span class="keyword">synchronized</span><span>(sChecker){</span></li><li><span>sChecker.reset();</span></li><li class="alt"><span>sChecker.update(data,</span><span class="number">0</span><span>,length);</span></li></ol></div><pre class="java" style="DISPLAY: none" name="code">/**@@ -85,16 +89,34 @@ public class MiniThumbFile { /*add 1 on google's version.*/ /*this version add check code for thumbdata.*/ private static final int MINI_THUMB_DATA_FILE_VERSION = 3 + 1; public static final int BYTES_PER_MINTHUMB = 17000; public static final int BYTES_PER_MINTHUMB = 17000; private static final int HEADER_SIZE = 1 + 8 + 4 + 8; private Uri mUri; private RandomAccessFile mMiniThumbFile; Map<Long,RandomAccessFile> mMiniThumbFilesMap = Collections.synchronizedMap(new HashMap<Long,RandomAccessFile>(5)); private FileChannel mChannel; private ByteBuffer mBuffer; private static Hashtable<String, MiniThumbFile> sThumbFiles = new Hashtable<String, MiniThumbFile>(); private static java.util.zip.Adler32 sChecker = new Adler32(); private static final long UNKNOWN_CHECK_CODE = -1; final static char SEPERATE_CHAR='_'; public static String[] parseFileName(String fileName) { String str=fileName; if(fileName==null) return null; int index=fileName.lastIndexOf("/"); if(index!=-1) { str=fileName.substring(index+1); } String strs[]=str.split(SEPERATE_CHAR+""); if(strs==null||strs.length!=4||(!str.startsWith(".thumbdata"))) { return null; } return strs; } /** * We store different types of thumbnails in different files. To remain backward compatibility, * we should hashcode of content://media/external/images/media remains the same.@@ -105,7 +127,18 @@ public class MiniThumbFile { } sThumbFiles.clear(); } private final static long getMiniThumbFileId(long id) { return (id>>8); } public final static int getMiniThumbDataFileBlockNum() { return (1<<8); } private final static long getPositionInMiniThumbFile(long id) { return (id&0xff)*BYTES_PER_MINTHUMB; } public static synchronized MiniThumbFile instance(Uri uri) { String type = uri.getPathSegments().get(1); MiniThumbFile file = sThumbFiles.get(type);@@ -120,10 +153,11 @@ public class MiniThumbFile { } private String randomAccessFilePath(int version) { String type = mUri.getPathSegments().get(1); String directoryName = Environment.getExternalStorageDirectory().toString() + "/DCIM/.thumbnails"; return directoryName + "/.thumbdata" + version + "-" + mUri.hashCode(); return directoryName + "/.thumbdata" + version + SEPERATE_CHAR + mUri.hashCode()+SEPERATE_CHAR+type; } /**@@ -131,18 +165,18 @@ public class MiniThumbFile { * @param uri the Uri same as instance(Uri uri). * @return */ public static String getThumbdataPath(Uri uri) { /*public static String getThumbdataPath(Uri uri) { String type = uri.getPathSegments().get(1); Uri thumbFileUri = Uri.parse("content://media/external/" + type + "/media"); String directoryName = Environment.getExternalStorageDirectory().toString() + "/DCIM/.thumbnails"; String path = directoryName + "/.thumbdata" + MINI_THUMB_DATA_FILE_VERSION + "-" + thumbFileUri.hashCode(); String path = directoryName + "/.thumbdata" + MINI_THUMB_DATA_FILE_VERSION +SEPERATE_CHAR + thumbFileUri.hashCode()+SEPERATE_CHAR+type; if (LOG) Log.i(TAG, "getThumbdataPath(" + uri + ") return " + path); return path; } }*/ private void removeOldFile() { String oldPath = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION - 1); private void removeOldMiniThumbDataFile(long miniThumbDataFileId) { String oldPath =getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION - 1,miniThumbDataFileId); File oldFile = new File(oldPath); if (oldFile.exists()) { try {@@ -152,35 +186,43 @@ public class MiniThumbFile { } } } private RandomAccessFile miniThumbDataFile() { if (mMiniThumbFile == null) { removeOldFile(); String path = randomAccessFilePath(MINI_THUMB_DATA_FILE_VERSION); File directory = new File(path).getParentFile(); if (!directory.isDirectory()) { if (!directory.mkdirs()) { Log.e(TAG, "Unable to create .thumbnails directory " + directory.toString()); } } final private String getMiniThumbDataFilePath(int version,long miniThumbDataFileId) { return randomAccessFilePath(version)+SEPERATE_CHAR+miniThumbDataFileId; } private RandomAccessFile miniThumbDataFile(final long miniThumbDataFileId) { return miniThumbDataFile(miniThumbDataFileId,false); } private RandomAccessFile miniThumbDataFile(final long miniThumbDataFileId,boolean onlyRead) { RandomAccessFile miniThumbFile=mMiniThumbFilesMap.get(miniThumbDataFileId); String path = getMiniThumbDataFilePath(MINI_THUMB_DATA_FILE_VERSION,miniThumbDataFileId); File f = new File(path); if (miniThumbFile == null||!f.exists()) {if(onlyRead)return null; removeOldMiniThumbDataFile(miniThumbDataFileId); File directory = new File(path).getParentFile(); if (!directory.isDirectory()) { if (!directory.mkdirs()) { Log.e(TAG, "Unable to create .thumbnails directory " + directory.toString()); } } try { mMiniThumbFile = new RandomAccessFile(f, "rw"); miniThumbFile = new RandomAccessFile(f, "rw"); } catch (IOException ex) { // Open as read-only so we can at least read the existing // thumbnails. try { mMiniThumbFile = new RandomAccessFile(f, "r");miniThumbFile = new RandomAccessFile(f, "r"); } catch (IOException ex2) { } } if (mMiniThumbFile != null) { mChannel = mMiniThumbFile.getChannel(); } mMiniThumbFilesMap.put(miniThumbDataFileId, miniThumbFile); } return mMiniThumbFile; return miniThumbFile; } public MiniThumbFile(Uri uri) {@@ -189,10 +231,19 @@ public class MiniThumbFile { } public synchronized void deactivate() { if (mMiniThumbFile != null) { if (mMiniThumbFilesMap != null) { Set<Long> keySet=mMiniThumbFilesMap.keySet(); try { mMiniThumbFile.close(); mMiniThumbFile = null;for(Long key:keySet){ RandomAccessFile file=mMiniThumbFilesMap.get(key); if(file!=null) { mMiniThumbFilesMap.put(key, null); file.close(); }}mMiniThumbFilesMap.clear(); } catch (IOException ex) { // ignore exception }@@ -205,18 +256,20 @@ public class MiniThumbFile { // check the mini thumb file for the right data. Right is // defined as having the right magic number at the offset // reserved for this "id". RandomAccessFile r = miniThumbDataFile(); final long miniThumbDataFileId=getMiniThumbFileId(id); RandomAccessFile r = miniThumbDataFile(miniThumbDataFileId,true); if (r != null) { long pos = id * BYTES_PER_MINTHUMB; FileChannel channel=r.getChannel(); long pos = getPositionInMiniThumbFile(id); FileLock lock = null; try { mBuffer.clear(); mBuffer.limit(1 + 8); lock = mChannel.lock(pos, 1 + 8, true); lock = channel.lock(pos, 1 + 8, true); // check that we can read the following 9 bytes // (1 for the "status" and 8 for the long) if (mChannel.read(mBuffer, pos) == 9) { if (channel.read(mBuffer, pos) == 9) { mBuffer.position(0); if (mBuffer.get() == 1) { return mBuffer.getLong();@@ -242,10 +295,12 @@ public class MiniThumbFile { public synchronized void saveMiniThumbToFile(byte[] data, long id, long magic) throws IOException { RandomAccessFile r = miniThumbDataFile(); final long miniThumbDataFileId=getMiniThumbFileId(id); RandomAccessFile r = miniThumbDataFile(miniThumbDataFileId); if (r == null) return; long pos = id * BYTES_PER_MINTHUMB; final long pos = getPositionInMiniThumbFile(id); FileChannel channel=r.getChannel(); FileLock lock = null; try { if (data != null) {@@ -266,14 +321,13 @@ public class MiniThumbFile {check = sChecker.getValue(); } mBuffer.putLong(check); if (LOG) Log.i(TAG, "saveMiniThumbToFile(" + id + ") flag=1, magic=" + magic + ", length=" + data.length + ", check=" + check); mBuffer.put(data); mBuffer.flip(); lock = mChannel.lock(pos, BYTES_PER_MINTHUMB, false); mChannel.write(mBuffer, pos); lock = channel.lock(pos, BYTES_PER_MINTHUMB, false); channel.write(mBuffer, pos); if (LOG) Log.i(TAG, "saveMiniThumbToFile(" + id + ") flag=1, magic=" + magic + ", length=" + data.length + ", check=" + check); } } catch (IOException ex) { Log.e(TAG, "couldn't save mini thumbnail data for "@@ -319,27 +373,29 @@ public class MiniThumbFile { * @return */ public synchronized byte[] getMiniThumbFromFile(long id, byte [] data, ThumbResult result) { RandomAccessFile r = miniThumbDataFile(); final long miniThumbDataFileId=getMiniThumbFileId(id); RandomAccessFile r = miniThumbDataFile(miniThumbDataFileId,true); if (r == null) return null; long pos = id * BYTES_PER_MINTHUMB; long pos = getPositionInMiniThumbFile(id); FileChannel channel=r.getChannel(); FileLock lock = null; try { mBuffer.clear(); lock = mChannel.lock(pos, BYTES_PER_MINTHUMB, true); int size = mChannel.read(mBuffer, pos); lock = channel.lock(pos, BYTES_PER_MINTHUMB, true); int size = channel.read(mBuffer, pos); if (size > 1 + 8 + 4 + 8) { // flag, magic, length, check code mBuffer.position(0); byte flag = mBuffer.get(); long magic = mBuffer.getLong(); int length = mBuffer.getInt(); long check = mBuffer.getLong(); if (LOG) Log.i(TAG, "getMiniThumbFromFile(" + id + ") flag=" + flag + ", magic=" + magic + ", length=" + length + ", check=" + check); long newCheck = UNKNOWN_CHECK_CODE; if (size >= 1 + 8 + 4 + 8 + length && data.length >= length) { mBuffer.get(data, 0, length); Log.i(TAG, " success to getMiniThumbFromFile(" + id + ") flag=" + flag + ", magic=" + magic + ", length=" + length + ", check=" + check); synchronized (sChecker) { sChecker.reset(); sChecker.update(data, 0, length); MediaScanner.java文件的修改如下：
<div class="dp-highlighter bg_java" sizcache="27" sizset="68"><div class="bar" sizcache="27" sizset="68"><div class="tools" sizcache="27" sizset="68"><strong>[java]</strong> <a target=_blank title="view plain" class="ViewSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">view plain</a><a target=_blank title="copy" class="CopyToClipboard" href="http://blog.csdn.net/fengye810130/article/details/9118221#">copy</a><a target=_blank title="print" class="PrintSource" href="http://blog.csdn.net/fengye810130/article/details/9118221#">print</a><a target=_blank title="?" class="About" href="http://blog.csdn.net/fengye810130/article/details/9118221#">?</a></div></div><ol class="dp-j"><li class="alt"><span><span>@@-</span><span class="number">1224</span><span>,</span><span class="number">14</span><span>+</span><span class="number">1224</span><span>,</span><span class="number">14</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MediaScanner</span></span></li><li><span>c.close();</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">if</span><span>(videoCount!=</span><span class="number">0</span><span>){</span></li><li class="alt"><span></span><span class="comment">/*if(videoCount!=0){</span></li><li><span><span class="comment">StringfullPathString=MiniThumbFile.getThumbdataPath(mVideoThumbsUri);</span></span></li><li class="alt"><span><span class="comment">existingFiles.remove(fullPathString);</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">if(imageCount!=0){</span></span></li><li><span><span class="comment">StringfullPathString=MiniThumbFile.getThumbdataPath(mThumbsUri);</span></span></li><li class="alt"><span><span class="comment">existingFiles.remove(fullPathString);</span></span></li><li><span><span class="comment">}</span></span></li><li class="alt"><span><span class="comment">}*/</span><span></span></span></li><li><span></span><span class="keyword">for</span><span>(StringfileToDelete:existingFiles){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)</span></li><li><span>Log.v(TAG,</span><span class="string">"fileToDeleteis"</span><span>+fileToDelete);</span></li><li class="alt"><span>@@-</span><span class="number">1247</span><span>,</span><span class="number">7</span><span>+</span><span class="number">1247</span><span>,</span><span class="number">163</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MediaScanner</span></li><li><span>e.printStackTrace();</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="comment">/*[robin_20120511*/</span><span></span></li><li><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>pruneDeadMiniThumbnailFiles(){</span></li><li class="alt"><span>HashSet<String>existingFiles=</span><span class="keyword">new</span><span>HashSet<String>();</span></li><li><span>Stringdirectory=Environment.getExternalStorageDirectory().toString()+</span><span class="string">"/DCIM/.thumbnails"</span><span>;</span></li><li class="alt"><span>Filefile=</span><span class="keyword">new</span><span>File(directory);</span></li><li><span>String[]files=(file).list();</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(files==</span><span class="keyword">null</span><span>){</span></li><li><span>files=</span><span class="keyword">new</span><span>String[</span><span class="number">0</span><span>];</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">for</span><span>(</span><span class="keyword">int</span><span>i=</span><span class="number">0</span><span>;i<files.length;i++){</span></li><li class="alt"><span>StringfullPathString=directory+</span><span class="string">"/"</span><span>+files[i];</span></li><li><span>existingFiles.add(fullPathString);</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>Cursorc=mMediaProvider.query(</span></li><li><span>mThumbsUri,</span></li><li class="alt"><span></span><span class="keyword">new</span><span>String[]{</span><span class="string">"_data"</span><span>},</span></li><li><span></span><span class="keyword">null</span><span>,</span></li><li class="alt"><span></span><span class="keyword">null</span><span>,</span></li><li><span></span><span class="keyword">null</span><span>);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(</span><span class="keyword">null</span><span>!=c){</span></li><li><span></span><span class="keyword">if</span><span>(c.moveToFirst()){</span></li><li class="alt"><span></span><span class="keyword">do</span><span>{</span></li><li><span>StringfullPathString=c.getString(</span><span class="number">0</span><span>);</span></li><li class="alt"><span>existingFiles.remove(fullPathString);</span></li><li><span>}</span><span class="keyword">while</span><span>(c.moveToNext());</span></li><li class="alt"><span>}</span></li><li><span>c.close();</span></li><li class="alt"><span>}</span></li><li><span>c=mMediaProvider.query(</span></li><li class="alt"><span>mVideoThumbsUri,</span></li><li><span></span><span class="keyword">new</span><span>String[]{</span><span class="string">"_data"</span><span>},</span></li><li class="alt"><span></span><span class="keyword">null</span><span>,</span></li><li><span></span><span class="keyword">null</span><span>,</span></li><li class="alt"><span></span><span class="keyword">null</span><span>);</span></li><li><span></span><span class="keyword">if</span><span>(</span><span class="keyword">null</span><span>!=c){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(c.moveToFirst()){</span></li><li><span></span><span class="keyword">do</span><span>{</span></li><li class="alt"><span>StringfullPathString=c.getString(</span><span class="number">0</span><span>);</span></li><li><span>existingFiles.remove(fullPathString);</span></li><li class="alt"><span>}</span><span class="keyword">while</span><span>(c.moveToNext());</span></li><li><span>}</span></li><li class="alt"><span>c.close();</span></li><li><span>}</span></li><li class="alt"><span>Stringstrs[];</span></li><li><span></span><span class="keyword">long</span><span>fileSN;</span></li><li class="alt"><span></span><span class="keyword">long</span><span>id0;</span></li><li><span></span><span class="keyword">long</span><span>id1;</span></li><li class="alt"><span></span><span class="keyword">int</span><span>blockNum=MiniThumbFile.getMiniThumbDataFileBlockNum();</span></li><li><span></span><span class="keyword">final</span><span>Stringselection_IMAGE=</span><span class="string">""</span><span>+Images.Thumbnails.IMAGE_ID+</span><span class="string">">=?AND"</span><span>+Images.Thumbnails.IMAGE_ID+</span><span class="string">"<?"</span><span>;</span></li><li class="alt"><span></span><span class="keyword">final</span><span>StringsortOrder_IMAGE=Images.Thumbnails.IMAGE_ID;</span></li><li><span></span><span class="keyword">final</span><span>Stringselection_VIDEO=</span><span class="string">""</span><span>+Video.Thumbnails.VIDEO_ID+</span><span class="string">">=?AND"</span><span>+Video.Thumbnails.VIDEO_ID+</span><span class="string">"<?"</span><span>;</span></li><li class="alt"><span></span><span class="keyword">final</span><span>StringsortOrder_VIDEO=Video.Thumbnails.VIDEO_ID;</span></li><li><span>HashSet<String>fileSet=</span><span class="keyword">new</span><span>HashSet<String>(existingFiles);</span></li><li class="alt"><span></span><span class="keyword">for</span><span>(StringfileToDelete:fileSet){</span></li><li><span>strs=MiniThumbFile.parseFileName(fileToDelete);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(strs==</span><span class="keyword">null</span><span>||strs.length!=</span><span class="number">4</span><span>)</span></li><li><span>{</span></li><li class="alt"><span>existingFiles.remove(fileToDelete);</span></li><li><span></span><span class="keyword">continue</span><span>;</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">if</span><span>(</span><span class="string">"images"</span><span>.equals(strs[</span><span class="number">2</span><span>])||</span><span class="string">"video"</span><span>.equals(strs[</span><span class="number">2</span><span>]))</span></li><li class="alt"><span>{</span></li><li><span>fileSN=Long.parseLong(strs[</span><span class="number">3</span><span>]);</span></li><li class="alt"><span>id0=blockNum*fileSN;</span></li><li><span>id1=blockNum*(fileSN+</span><span class="number">1</span><span>);</span></li><li class="alt"><span></span><span class="keyword">final</span><span>String[]selectionArgs=</span><span class="keyword">new</span><span>String[]{id0+</span><span class="string">""</span><span>,id1+</span><span class="string">""</span><span>};</span></li><li><span></span><span class="keyword">if</span><span>(</span><span class="string">"images"</span><span>.equals(strs[</span><span class="number">2</span><span>]))</span></li><li class="alt"><span>{</span></li><li><span></span></li><li class="alt"><span>c=mMediaProvider.query(</span></li><li><span>mThumbsUri,</span></li><li class="alt"><span></span><span class="keyword">new</span><span>String[]{Images.Thumbnails.IMAGE_ID},</span></li><li><span>selection_IMAGE,</span></li><li class="alt"><span>selectionArgs,</span></li><li><span>sortOrder_IMAGE);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(</span><span class="keyword">null</span><span>!=c){</span></li><li><span></span><span class="keyword">if</span><span>(c.getCount()></span><span class="number">0</span><span>){</span></li><li class="alt"><span></span></li><li><span>existingFiles.remove(fileToDelete);</span></li><li class="alt"><span>}</span></li><li><span>c.close();</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">else</span><span></span><span class="keyword">if</span><span>(</span><span class="string">"video"</span><span>.equals(strs[</span><span class="number">2</span><span>]))</span></li><li><span>{</span></li><li class="alt"><span>c=mMediaProvider.query(</span></li><li><span>mVideoThumbsUri,</span></li><li class="alt"><span></span><span class="keyword">new</span><span>String[]{Video.Thumbnails.VIDEO_ID},</span></li><li><span>selection_VIDEO,</span></li><li class="alt"><span>selectionArgs,</span></li><li><span>sortOrder_VIDEO);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(</span><span class="keyword">null</span><span>!=c){</span></li><li><span></span><span class="keyword">if</span><span>(c.getCount()></span><span class="number">0</span><span>){</span></li><li class="alt"><span>existingFiles.remove(fileToDelete);</span></li><li><span>}</span></li><li class="alt"><span>c.close();</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">else</span><span></span></li><li><span>{</span></li><li class="alt"><span>existingFiles.remove(fileToDelete);</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">for</span><span>(StringfileToDelete:existingFiles){</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(LOG)</span></li><li><span>Log.v(TAG,</span><span class="string">"fileToDeleteis"</span><span>+fileToDelete);</span></li><li class="alt"><span></span><span class="keyword">try</span><span>{</span></li><li><span>(</span><span class="keyword">new</span><span>File(fileToDelete)).delete();</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(SecurityExceptionex){</span></li><li><span>ex.printStackTrace();</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span>file=</span><span class="keyword">new</span><span>File(directory);</span></li><li><span></span><span class="keyword">long</span><span>freeDiskSpape=(file.getUsableSpace()>></span><span class="number">20</span><span>);</span></li><li class="alt"><span></span><span class="comment">/*</span></li><li><span><span class="comment">*whenthefreeDiskisverylow(<100M),deleteallMiniThumbFile</span></span></li><li class="alt"><span><span class="comment">*/</span><span></span></span></li><li><span></span><span class="keyword">if</span><span>(freeDiskSpape<</span><span class="number">100</span><span>)</span></li><li class="alt"><span>{</span></li><li><span>files=(file).list();</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(files==</span><span class="keyword">null</span><span>){</span></li><li><span>files=</span><span class="keyword">new</span><span>String[</span><span class="number">0</span><span>];</span></li><li class="alt"><span>}</span></li><li><span></span><span class="keyword">for</span><span>(</span><span class="keyword">int</span><span>i=</span><span class="number">0</span><span>;i<files.length;i++){</span></li><li class="alt"><span>StringfullPathString=directory+</span><span class="string">"/"</span><span>+files[i];</span></li><li><span>existingFiles.add(fullPathString);</span></li><li class="alt"><span>}</span></li><li><span>fileSet=</span><span class="keyword">new</span><span>HashSet<String>(existingFiles);</span></li><li class="alt"><span></span><span class="keyword">for</span><span>(StringfileToDelete:fileSet){</span></li><li><span>strs=MiniThumbFile.parseFileName(fileToDelete);</span></li><li class="alt"><span></span><span class="keyword">if</span><span>(strs==</span><span class="keyword">null</span><span>||strs.length!=</span><span class="number">4</span><span>)</span></li><li><span>{</span></li><li class="alt"><span>existingFiles.remove(fileToDelete);</span></li><li><span></span><span class="keyword">continue</span><span>;</span></li><li class="alt"><span>}</span></li><li><span>}</span></li><li class="alt"><span></span><span class="keyword">for</span><span>(StringfileToDelete:existingFiles){</span></li><li><span></span><span class="keyword">if</span><span>(LOG)</span></li><li class="alt"><span>Log.v(TAG,</span><span class="string">"MemeroyisveryLow.deleteMiniThumbFile:"</span><span>+fileToDelete);</span></li><li><span></span><span class="keyword">try</span><span>{</span></li><li class="alt"><span>(</span><span class="keyword">new</span><span>File(fileToDelete)).delete();</span></li><li><span>}</span><span class="keyword">catch</span><span>(SecurityExceptionex){</span></li><li class="alt"><span>ex.printStackTrace();</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span>}</span></li><li><span>Log.v(TAG,</span><span class="string">"pruneDeadMiniThumbnailFiles..."</span><span>+c);</span></li><li class="alt"><span>}</span><span class="keyword">catch</span><span>(RemoteExceptione){</span></li><li><span></span><span class="comment">/*Wewillsoonbekilled...*/</span><span></span></li><li class="alt"><span>e.printStackTrace();</span></li><li><span>}</span></li><li class="alt"><span>}</span></li><li><span></span><span class="comment">/*robin_20120511]*/</span><span></span></li><li class="alt"><span></span><span class="keyword">private</span><span></span><span class="keyword">void</span><span>postscan(String[]directories)</span><span class="keyword">throws</span><span>RemoteException{</span></li><li><span>Iterator<FileCacheEntry>iterator=mFileCache.values().iterator();</span></li><li class="alt"><span>@@-</span><span class="number">1306</span><span>,</span><span class="number">8</span><span>+</span><span class="number">1462</span><span>,</span><span class="number">12</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MediaScanner</span></li><li><span></span><span class="keyword">if</span><span>((mOriginalCount==</span><span class="number">0</span><span>||mOriginalVideoCount==</span><span class="number">0</span><span>)</span></li><li class="alt"><span>&&mImagesUri.equals(Images.Media.getContentUri(</span><span class="string">"external"</span><span>))){</span></li><li><span>pruneDeadThumbnailFiles();</span></li><li class="alt"><span>}</span><span class="comment">/*[robin_20120511*/</span><span></span></li><li><span></span><span class="keyword">else</span><span></span><span class="keyword">if</span><span>(mImagesUri.equals(Images.Media.getContentUri(</span><span class="string">"external"</span><span>)))</span></li><li class="alt"><span>{</span></li><li><span>pruneDeadMiniThumbnailFiles();</span></li><li class="alt"><span>}</span></li><li><span></span></li><li class="alt"><span></span><span class="comment">/*robin_20120511]*/</span><span></span></li><li><span></span><span class="comment">/*allowGCtocleanup*/</span><span></span></li><li class="alt"><span>mPlayLists=</span><span class="keyword">null</span><span>;</span></li><li><span>mFileCache=</span><span class="keyword">null</span><span>;</span></li><li class="alt"><span>@@-</span><span class="number">1399</span><span>,</span><span class="number">7</span><span>+</span><span class="number">1559</span><span>,</span><span class="number">12</span><span>@@</span><span class="keyword">public</span><span></span><span class="keyword">class</span><span>MediaScanner</span></li><li><span></span><span class="keyword">long</span><span>prune=System.currentTimeMillis();</span></li><li class="alt"><span>pruneDeadThumbnailFiles();</span></li><li><span></span><span class="keyword">if</span><span>(LOG)Log.d(TAG,</span><span class="string">"mtkPostscan:pruneDeadThumbnailFilestakes"</span><span>+(System.currentTimeMillis()-prune)+</span><span class="string">"ms."</span><span>);</span></li><li class="alt"><span>}</span><span class="comment">/*[robin_20120511*/</span><span></span></li><li><span></span><span class="keyword">else</span><span></span><span class="keyword">if</span><span>(mImagesUri.equals(Images.Media.getContentUri(</span><span class="string">"external"</span><span>)))</span></li><li class="alt"><span>{</span></li><li><span>pruneDeadMiniThumbnailFiles();</span></li><li class="alt"><span>}</span></li><li><span></span><span class="comment">/*robin_20120511]*/</span><span></span></li><li class="alt"><span></span></li><li><span></span><span class="comment">//allowGCtocleanup </span><span></span></li><li class="alt"><span>mPlayLists=</span><span class="keyword">null</span><span>;</span></li></ol></div><pre class="java" style="DISPLAY: none" name="code">@@ -1224,14 +1224,14 @@ public class MediaScanner c.close(); } if (videoCount != 0) { /*if (videoCount != 0) { String fullPathString = MiniThumbFile.getThumbdataPath(mVideoThumbsUri); existingFiles.remove(fullPathString); } if (imageCount != 0) { String fullPathString = MiniThumbFile.getThumbdataPath(mThumbsUri); existingFiles.remove(fullPathString); } }*/ for (String fileToDelete : existingFiles) { if (LOG) Log.v(TAG, "fileToDelete is " + fileToDelete);@@ -1247,7 +1247,163 @@ public class MediaScanner e.printStackTrace(); } } /*[robin_20120511*/ private void pruneDeadMiniThumbnailFiles() { HashSet<String> existingFiles = new HashSet<String>(); String directory = Environment.getExternalStorageDirectory().toString() + "/DCIM/.thumbnails"; File file=new File(directory); String [] files = (file).list(); if (files == null) { files = new String[0]; } for (int i=0; i < files.length; i++) { String fullPathString = directory + "/" + files[i]; existingFiles.add(fullPathString); } try { Cursor c = mMediaProvider.query( mThumbsUri, new String [] { "_data" }, null, null, null); if (null != c) { if (c.moveToFirst()) { do { String fullPathString = c.getString(0); existingFiles.remove(fullPathString); } while (c.moveToNext()); } c.close(); } c = mMediaProvider.query( mVideoThumbsUri, new String [] { "_data" }, null, null, null); if (null != c) { if (c.moveToFirst()) { do { String fullPathString = c.getString(0); existingFiles.remove(fullPathString); } while (c.moveToNext()); } c.close(); } String strs[]; long fileSN; long id0; long id1; int blockNum=MiniThumbFile.getMiniThumbDataFileBlockNum(); final String selection_IMAGE=" "+Images.Thumbnails.IMAGE_ID+">=? AND "+Images.Thumbnails.IMAGE_ID+"<?"; final String sortOrder_IMAGE=Images.Thumbnails.IMAGE_ID; final String selection_VIDEO=" "+Video.Thumbnails.VIDEO_ID+">=? AND "+Video.Thumbnails.VIDEO_ID+"<?"; final String sortOrder_VIDEO=Video.Thumbnails.VIDEO_ID; HashSet<String> fileSet=new HashSet<String>(existingFiles); for (String fileToDelete : fileSet) { strs=MiniThumbFile.parseFileName(fileToDelete); if(strs==null||strs.length!=4) { existingFiles.remove(fileToDelete); continue; } if("images".equals(strs[2])||"video".equals(strs[2])) { fileSN=Long.parseLong(strs[3]); id0=blockNum*fileSN; id1=blockNum*(fileSN+1); final String[] selectionArgs= new String[]{id0+"",id1+""}; if("images".equals(strs[2])) { c = mMediaProvider.query( mThumbsUri, new String [] { Images.Thumbnails.IMAGE_ID }, selection_IMAGE, selectionArgs, sortOrder_IMAGE); if (null != c) { if (c.getCount()>0) { existingFiles.remove(fileToDelete); } c.close(); } } else if ("video".equals(strs[2])) { c = mMediaProvider.query( mVideoThumbsUri, new String [] { Video.Thumbnails.VIDEO_ID }, selection_VIDEO, selectionArgs, sortOrder_VIDEO); if (null != c) { if (c.getCount()>0) { existingFiles.remove(fileToDelete); } c.close(); } } } else { existingFiles.remove(fileToDelete); } } for (String fileToDelete : existingFiles) { if (LOG) Log.v(TAG, "fileToDelete is " + fileToDelete); try { (new File(fileToDelete)).delete(); } catch (SecurityException ex) { ex.printStackTrace(); } } file=new File(directory); long freeDiskSpape=(file.getUsableSpace()>>20); /* * when the free Disk is very low(<100M),delete all MiniThumbFile */ if(freeDiskSpape<100) {files = (file).list(); if (files == null) { files = new String[0]; } for (int i=0; i < files.length; i++) { String fullPathString = directory + "/" + files[i]; existingFiles.add(fullPathString); } fileSet=new HashSet<String>(existingFiles); for (String fileToDelete : fileSet) { strs=MiniThumbFile.parseFileName(fileToDelete); if(strs==null||strs.length!=4) {existingFiles.remove(fileToDelete);continue; } } for (String fileToDelete : existingFiles) { if (LOG) Log.v(TAG, "Memeroy is very Low.delete MiniThumbFile:" + fileToDelete); try { (new File(fileToDelete)).delete(); } catch (SecurityException ex) { ex.printStackTrace(); } } } Log.v(TAG, "pruneDeadMiniThumbnailFiles... " + c); } catch (RemoteException e) { /* We will soon be killed...*/ e.printStackTrace(); } } /*robin_20120511]*/ private void postscan(String[] directories) throws RemoteException { Iterator<FileCacheEntry> iterator = mFileCache.values().iterator();@@ -1306,8 +1462,12 @@ public class MediaScanner if ((mOriginalCount == 0 || mOriginalVideoCount == 0) && mImagesUri.equals(Images.Media.getContentUri("external"))) { pruneDeadThumbnailFiles(); }/*[robin_20120511*/ else if (mImagesUri.equals(Images.Media.getContentUri("external"))) { pruneDeadMiniThumbnailFiles(); } /*robin_20120511]*/ /* allow GC to clean up*/ mPlayLists = null; mFileCache = null;@@ -1399,7 +1559,12 @@ public class MediaScanner long prune = System.currentTimeMillis(); pruneDeadThumbnailFiles(); if (LOG) Log.d(TAG, "mtkPostscan: pruneDeadThumbnailFiles takes " + (System.currentTimeMillis() - prune) + "ms."); }/*[robin_20120511*/ else if (mImagesUri.equals(Images.Media.getContentUri("external"))) { pruneDeadMiniThumbnailFiles(); } /*robin_20120511]*/ // allow GC to clean up mPlayLists = null; 结束！
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