diskfileitem.html

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<a name="523" href="#523">523</a> <em>     *         for storing the contensts of the file.</em>
<a name="524" href="#524">524</a> <em>     *</em>
<a name="525" href="#525">525</a> <em>     * @throws IOException if an error occurs.</em>
<a name="526" href="#526">526</a> <em>     */</em>
<a name="527" href="#527">527</a>     <strong>public</strong> OutputStream getOutputStream()
<a name="528" href="#528">528</a>         throws IOException {
<a name="529" href="#529">529</a>         <strong>if</strong> (dfos == <strong>null</strong>) {
<a name="530" href="#530">530</a>             File outputFile = getTempFile();
<a name="531" href="#531">531</a>             dfos = <strong>new</strong> DeferredFileOutputStream(sizeThreshold, outputFile);
<a name="532" href="#532">532</a>         }
<a name="533" href="#533">533</a>         <strong>return</strong> dfos;
<a name="534" href="#534">534</a>     }
<a name="535" href="#535">535</a> 
<a name="536" href="#536">536</a> 
<a name="537" href="#537">537</a>     <em class="comment">// --------------------------------------------------------- Public methods</em>
<a name="538" href="#538">538</a> 
<a name="539" href="#539">539</a> 
<a name="540" href="#540">540</a>     <em>/**<em>*</em></em>
<a name="541" href="#541">541</a> <em>     * Returns the {@link java.io.File} object for the &lt;code>FileItem&lt;/code>'s</em>
<a name="542" href="#542">542</a> <em>     * data's temporary location on the disk. Note that for</em>
<a name="543" href="#543">543</a> <em>     * &lt;code>FileItem&lt;/code>s that have their data stored in memory,</em>
<a name="544" href="#544">544</a> <em>     * this method will return &lt;code>null&lt;/code>. When handling large</em>
<a name="545" href="#545">545</a> <em>     * files, you can use {@link java.io.File#renameTo(java.io.File)} to</em>
<a name="546" href="#546">546</a> <em>     * move the file to new location without copying the data, if the</em>
<a name="547" href="#547">547</a> <em>     * source and destination locations reside within the same logical</em>
<a name="548" href="#548">548</a> <em>     * volume.</em>
<a name="549" href="#549">549</a> <em>     *</em>
<a name="550" href="#550">550</a> <em>     * @return The data file, or &lt;code>null&lt;/code> if the data is stored in</em>
<a name="551" href="#551">551</a> <em>     *         memory.</em>
<a name="552" href="#552">552</a> <em>     */</em>
<a name="553" href="#553">553</a>     <strong>public</strong> File getStoreLocation() {
<a name="554" href="#554">554</a>         <strong>return</strong> dfos.getFile();
<a name="555" href="#555">555</a>     }
<a name="556" href="#556">556</a> 
<a name="557" href="#557">557</a> 
<a name="558" href="#558">558</a>     <em class="comment">// ------------------------------------------------------ Protected methods</em>
<a name="559" href="#559">559</a> 
<a name="560" href="#560">560</a> 
<a name="561" href="#561">561</a>     <em>/**<em>*</em></em>
<a name="562" href="#562">562</a> <em>     * Removes the file contents from the temporary storage.</em>
<a name="563" href="#563">563</a> <em>     */</em>
<a name="564" href="#564">564</a>     <strong>protected</strong> <strong>void</strong> finalize() {
<a name="565" href="#565">565</a>         File outputFile = dfos.getFile();
<a name="566" href="#566">566</a> 
<a name="567" href="#567">567</a>         <strong>if</strong> (outputFile != <strong>null</strong> &amp;&amp; outputFile.exists()) {
<a name="568" href="#568">568</a>             outputFile.delete();
<a name="569" href="#569">569</a>         }
<a name="570" href="#570">570</a>     }
<a name="571" href="#571">571</a> 
<a name="572" href="#572">572</a> 
<a name="573" href="#573">573</a>     <em>/**<em>*</em></em>
<a name="574" href="#574">574</a> <em>     * Creates and returns a {@link java.io.File File} representing a uniquely</em>
<a name="575" href="#575">575</a> <em>     * named temporary file in the configured repository path. The lifetime of</em>
<a name="576" href="#576">576</a> <em>     * the file is tied to the lifetime of the &lt;code>FileItem&lt;/code> instance;</em>
<a name="577" href="#577">577</a> <em>     * the file will be deleted when the instance is garbage collected.</em>
<a name="578" href="#578">578</a> <em>     *</em>
<a name="579" href="#579">579</a> <em>     * @return The {@link java.io.File File} to be used for temporary storage.</em>
<a name="580" href="#580">580</a> <em>     */</em>
<a name="581" href="#581">581</a>     <strong>protected</strong> File getTempFile() {
<a name="582" href="#582">582</a>         File tempDir = repository;
<a name="583" href="#583">583</a>         <strong>if</strong> (tempDir == <strong>null</strong>) {
<a name="584" href="#584">584</a>             tempDir = <strong>new</strong> File(System.getProperty(<span class="string">"java.io.tmpdir"</span>));
<a name="585" href="#585">585</a>         }
<a name="586" href="#586">586</a> 
<a name="587" href="#587">587</a>         String fileName = <span class="string">"upload_"</span> + UID + <span class="string">"_"</span> + getUniqueId() + <span class="string">".tmp"</span>;
<a name="588" href="#588">588</a> 
<a name="589" href="#589">589</a>         File f = <strong>new</strong> File(tempDir, fileName);
<a name="590" href="#590">590</a>         FileCleaner.track(f, <strong>this</strong>);
<a name="591" href="#591">591</a>         <strong>return</strong> f;
<a name="592" href="#592">592</a>     }
<a name="593" href="#593">593</a> 
<a name="594" href="#594">594</a> 
<a name="595" href="#595">595</a>     <em class="comment">// -------------------------------------------------------- Private methods</em>
<a name="596" href="#596">596</a> 
<a name="597" href="#597">597</a> 
<a name="598" href="#598">598</a>     <em>/**<em>*</em></em>
<a name="599" href="#599">599</a> <em>     * Returns an identifier that is unique within the class loader used to</em>
<a name="600" href="#600">600</a> <em>     * load this class, but does not have random-like apearance.</em>
<a name="601" href="#601">601</a> <em>     *</em>
<a name="602" href="#602">602</a> <em>     * @return A String with the non-random looking instance identifier.</em>
<a name="603" href="#603">603</a> <em>     */</em>
<a name="604" href="#604">604</a>     <strong>private</strong> <strong>static</strong> String getUniqueId() {
<a name="605" href="#605">605</a>         <strong>final</strong> <strong>int</strong> limit = 100000000;
<a name="606" href="#606">606</a>         <strong>int</strong> current;
<a name="607" href="#607">607</a>         <strong>synchronized</strong> (DiskFileItem.<strong>class</strong>) {
<a name="608" href="#608">608</a>             current = counter++;
<a name="609" href="#609">609</a>         }
<a name="610" href="#610">610</a>         String id = Integer.toString(current);
<a name="611" href="#611">611</a> 
<a name="612" href="#612">612</a>         <em class="comment">// If you manage to get more than 100 million of ids, you'll</em>
<a name="613" href="#613">613</a>         <em class="comment">// start getting ids longer than 8 characters.</em>
<a name="614" href="#614">614</a>         <strong>if</strong> (current &lt; limit) {
<a name="615" href="#615">615</a>             id = (<span class="string">"00000000"</span> + id).substring(id.length());
<a name="616" href="#616">616</a>         }
<a name="617" href="#617">617</a>         <strong>return</strong> id;
<a name="618" href="#618">618</a>     }
<a name="619" href="#619">619</a> 
<a name="620" href="#620">620</a> 
<a name="621" href="#621">621</a> 
<a name="622" href="#622">622</a> 
<a name="623" href="#623">623</a>     <em>/**<em>*</em></em>
<a name="624" href="#624">624</a> <em>     * Returns a string representation of this object.</em>
<a name="625" href="#625">625</a> <em>     *</em>
<a name="626" href="#626">626</a> <em>     * @return a string representation of this object.</em>
<a name="627" href="#627">627</a> <em>     */</em>
<a name="628" href="#628">628</a>     <strong>public</strong> String toString() {
<a name="629" href="#629">629</a>         <strong>return</strong> <span class="string">"name="</span> + <strong>this</strong>.getName()
<a name="630" href="#630">630</a>             + <span class="string">", StoreLocation="</span>
<a name="631" href="#631">631</a>             + String.valueOf(<strong>this</strong>.getStoreLocation())
<a name="632" href="#632">632</a>             + <span class="string">", size="</span>
<a name="633" href="#633">633</a>             + <strong>this</strong>.getSize()
<a name="634" href="#634">634</a>             + <span class="string">"bytes, "</span>
<a name="635" href="#635">635</a>             + <span class="string">"isFormField="</span> + isFormField()
<a name="636" href="#636">636</a>             + <span class="string">", FieldName="</span>
<a name="637" href="#637">637</a>             + <strong>this</strong>.getFieldName();
<a name="638" href="#638">638</a>     }
<a name="639" href="#639">639</a> 
<a name="640" href="#640">640</a> 
<a name="641" href="#641">641</a>     <em class="comment">// -------------------------------------------------- Serialization methods</em>
<a name="642" href="#642">642</a> 
<a name="643" href="#643">643</a> 
<a name="644" href="#644">644</a>     <em>/**<em>*</em></em>
<a name="645" href="#645">645</a> <em>     * Writes the state of this object during serialization.</em>
<a name="646" href="#646">646</a> <em>     *</em>
<a name="647" href="#647">647</a> <em>     * @param out The stream to which the state should be written.</em>
<a name="648" href="#648">648</a> <em>     *</em>
<a name="649" href="#649">649</a> <em>     * @throws IOException if an error occurs.</em>
<a name="650" href="#650">650</a> <em>     */</em>
<a name="651" href="#651">651</a>     <strong>private</strong> <strong>void</strong> writeObject(ObjectOutputStream out) throws IOException {
<a name="652" href="#652">652</a>         <em class="comment">// Read the data</em>
<a name="653" href="#653">653</a>         <strong>if</strong> (dfos.isInMemory()) {
<a name="654" href="#654">654</a>             cachedContent = get();
<a name="655" href="#655">655</a>         } <strong>else</strong> {
<a name="656" href="#656">656</a>             cachedContent = <strong>null</strong>;
<a name="657" href="#657">657</a>             dfosFile = dfos.getFile();
<a name="658" href="#658">658</a>         }
<a name="659" href="#659">659</a> 
<a name="660" href="#660">660</a>         <em class="comment">// write out values</em>
<a name="661" href="#661">661</a>         out.defaultWriteObject();
<a name="662" href="#662">662</a>     }
<a name="663" href="#663">663</a> 
<a name="664" href="#664">664</a>     <em>/**<em>*</em></em>
<a name="665" href="#665">665</a> <em>     * Reads the state of this object during deserialization.</em>
<a name="666" href="#666">666</a> <em>     *</em>
<a name="667" href="#667">667</a> <em>     * @param in The stream from which the state should be read.</em>
<a name="668" href="#668">668</a> <em>     *</em>
<a name="669" href="#669">669</a> <em>     * @throws IOException if an error occurs.</em>
<a name="670" href="#670">670</a> <em>     * @throws ClassNotFoundException if class cannot be found.</em>
<a name="671" href="#671">671</a> <em>     */</em>
<a name="672" href="#672">672</a>     <strong>private</strong> <strong>void</strong> readObject(ObjectInputStream in)
<a name="673" href="#673">673</a>             throws IOException, ClassNotFoundException {
<a name="674" href="#674">674</a>         <em class="comment">// read values</em>
<a name="675" href="#675">675</a>         in.defaultReadObject();
<a name="676" href="#676">676</a> 
<a name="677" href="#677">677</a>         OutputStream output = getOutputStream();
<a name="678" href="#678">678</a>         <strong>if</strong> (cachedContent != <strong>null</strong>) {
<a name="679" href="#679">679</a>             output.write(cachedContent);
<a name="680" href="#680">680</a>         } <strong>else</strong> {
<a name="681" href="#681">681</a>             FileInputStream input = <strong>new</strong> FileInputStream(dfosFile);
<a name="682" href="#682">682</a> 
<a name="683" href="#683">683</a>             IOUtils.copy(input, output);
<a name="684" href="#684">684</a>             dfosFile.delete();
<a name="685" href="#685">685</a>             dfosFile = <strong>null</strong>;
<a name="686" href="#686">686</a>         }
<a name="687" href="#687">687</a>         output.close();
<a name="688" href="#688">688</a> 
<a name="689" href="#689">689</a>         cachedContent = <strong>null</strong>;
<a name="690" href="#690">690</a>     }
<a name="691" href="#691">691</a> 
<a name="692" href="#692">692</a> }
</pre>
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