diskfileitem.html

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<a name="346" href="#346">346</a> <em>     * contents of the file.</em>
<a name="347" href="#347">347</a> <em>     *</em>
<a name="348" href="#348">348</a> <em>     * @return The contents of the file, as a string.</em>
<a name="349" href="#349">349</a> <em>     *</em>
<a name="350" href="#350">350</a> <em>     * @todo Consider making this method throw UnsupportedEncodingException.</em>
<a name="351" href="#351">351</a> <em>     */</em>
<a name="352" href="#352">352</a>     <strong>public</strong> String getString() {
<a name="353" href="#353">353</a>         byte[] rawdata = get();
<a name="354" href="#354">354</a>         String charset = getCharSet();
<a name="355" href="#355">355</a>         <strong>if</strong> (charset == <strong>null</strong>) {
<a name="356" href="#356">356</a>             charset = DEFAULT_CHARSET;
<a name="357" href="#357">357</a>         }
<a name="358" href="#358">358</a>         <strong>try</strong> {
<a name="359" href="#359">359</a>             <strong>return</strong> <strong>new</strong> String(rawdata, charset);
<a name="360" href="#360">360</a>         } <strong>catch</strong> (UnsupportedEncodingException e) {
<a name="361" href="#361">361</a>             <strong>return</strong> <strong>new</strong> String(rawdata);
<a name="362" href="#362">362</a>         }
<a name="363" href="#363">363</a>     }
<a name="364" href="#364">364</a> 
<a name="365" href="#365">365</a> 
<a name="366" href="#366">366</a>     <em>/**<em>*</em></em>
<a name="367" href="#367">367</a> <em>     * A convenience method to write an uploaded item to disk. The client code</em>
<a name="368" href="#368">368</a> <em>     * is not concerned with whether or not the item is stored in memory, or on</em>
<a name="369" href="#369">369</a> <em>     * disk in a temporary location. They just want to write the uploaded item</em>
<a name="370" href="#370">370</a> <em>     * to a file.</em>
<a name="371" href="#371">371</a> <em>     * &lt;p></em>
<a name="372" href="#372">372</a> <em>     * This implementation first attempts to rename the uploaded item to the</em>
<a name="373" href="#373">373</a> <em>     * specified destination file, if the item was originally written to disk.</em>
<a name="374" href="#374">374</a> <em>     * Otherwise, the data will be copied to the specified file.</em>
<a name="375" href="#375">375</a> <em>     * &lt;p></em>
<a name="376" href="#376">376</a> <em>     * This method is only guaranteed to work &lt;em>once&lt;/em>, the first time it</em>
<a name="377" href="#377">377</a> <em>     * is invoked for a particular item. This is because, in the event that the</em>
<a name="378" href="#378">378</a> <em>     * method renames a temporary file, that file will no longer be available</em>
<a name="379" href="#379">379</a> <em>     * to copy or rename again at a later time.</em>
<a name="380" href="#380">380</a> <em>     *</em>
<a name="381" href="#381">381</a> <em>     * @param file The &lt;code>File&lt;/code> into which the uploaded item should</em>
<a name="382" href="#382">382</a> <em>     *             be stored.</em>
<a name="383" href="#383">383</a> <em>     *</em>
<a name="384" href="#384">384</a> <em>     * @throws Exception if an error occurs.</em>
<a name="385" href="#385">385</a> <em>     */</em>
<a name="386" href="#386">386</a>     <strong>public</strong> <strong>void</strong> write(File file) throws Exception {
<a name="387" href="#387">387</a>         <strong>if</strong> (isInMemory()) {
<a name="388" href="#388">388</a>             FileOutputStream fout = <strong>null</strong>;
<a name="389" href="#389">389</a>             <strong>try</strong> {
<a name="390" href="#390">390</a>                 fout = <strong>new</strong> FileOutputStream(file);
<a name="391" href="#391">391</a>                 fout.write(get());
<a name="392" href="#392">392</a>             } <strong>finally</strong> {
<a name="393" href="#393">393</a>                 <strong>if</strong> (fout != <strong>null</strong>) {
<a name="394" href="#394">394</a>                     fout.close();
<a name="395" href="#395">395</a>                 }
<a name="396" href="#396">396</a>             }
<a name="397" href="#397">397</a>         } <strong>else</strong> {
<a name="398" href="#398">398</a>             File outputFile = getStoreLocation();
<a name="399" href="#399">399</a>             <strong>if</strong> (outputFile != <strong>null</strong>) {
<a name="400" href="#400">400</a>                 <em class="comment">// Save the length of the file</em>
<a name="401" href="#401">401</a>                 size = outputFile.length();
<a name="402" href="#402">402</a>                 <em class="comment">/*</em>
<a name="403" href="#403">403</a> <em class="comment">                 * The uploaded file is being stored on disk</em>
<a name="404" href="#404">404</a> <em class="comment">                 * in a temporary location so move it to the</em>
<a name="405" href="#405">405</a> <em class="comment">                 * desired file.</em>
<a name="406" href="#406">406</a> <em class="comment">                 */</em>
<a name="407" href="#407">407</a>                 <strong>if</strong> (!outputFile.renameTo(file)) {
<a name="408" href="#408">408</a>                     BufferedInputStream in = <strong>null</strong>;
<a name="409" href="#409">409</a>                     BufferedOutputStream out = <strong>null</strong>;
<a name="410" href="#410">410</a>                     <strong>try</strong> {
<a name="411" href="#411">411</a>                         in = <strong>new</strong> BufferedInputStream(
<a name="412" href="#412">412</a>                             <strong>new</strong> FileInputStream(outputFile));
<a name="413" href="#413">413</a>                         out = <strong>new</strong> BufferedOutputStream(
<a name="414" href="#414">414</a>                                 <strong>new</strong> FileOutputStream(file));
<a name="415" href="#415">415</a>                         IOUtils.copy(in, out);
<a name="416" href="#416">416</a>                     } <strong>finally</strong> {
<a name="417" href="#417">417</a>                         <strong>if</strong> (in != <strong>null</strong>) {
<a name="418" href="#418">418</a>                             <strong>try</strong> {
<a name="419" href="#419">419</a>                                 in.close();
<a name="420" href="#420">420</a>                             } <strong>catch</strong> (IOException e) {
<a name="421" href="#421">421</a>                                 <em class="comment">// ignore</em>
<a name="422" href="#422">422</a>                             }
<a name="423" href="#423">423</a>                         }
<a name="424" href="#424">424</a>                         <strong>if</strong> (out != <strong>null</strong>) {
<a name="425" href="#425">425</a>                             <strong>try</strong> {
<a name="426" href="#426">426</a>                                 out.close();
<a name="427" href="#427">427</a>                             } <strong>catch</strong> (IOException e) {
<a name="428" href="#428">428</a>                                 <em class="comment">// ignore</em>
<a name="429" href="#429">429</a>                             }
<a name="430" href="#430">430</a>                         }
<a name="431" href="#431">431</a>                     }
<a name="432" href="#432">432</a>                 }
<a name="433" href="#433">433</a>             } <strong>else</strong> {
<a name="434" href="#434">434</a>                 <em class="comment">/*</em>
<a name="435" href="#435">435</a> <em class="comment">                 * For whatever reason we cannot write the</em>
<a name="436" href="#436">436</a> <em class="comment">                 * file to disk.</em>
<a name="437" href="#437">437</a> <em class="comment">                 */</em>
<a name="438" href="#438">438</a>                 <strong>throw</strong> <strong>new</strong> <a href="../../../../../org/apache/commons/fileupload/FileUploadException.html">FileUploadException</a>(
<a name="439" href="#439">439</a>                     <span class="string">"Cannot write uploaded file to disk!"</span>);
<a name="440" href="#440">440</a>             }
<a name="441" href="#441">441</a>         }
<a name="442" href="#442">442</a>     }
<a name="443" href="#443">443</a> 
<a name="444" href="#444">444</a> 
<a name="445" href="#445">445</a>     <em>/**<em>*</em></em>
<a name="446" href="#446">446</a> <em>     * Deletes the underlying storage for a file item, including deleting any</em>
<a name="447" href="#447">447</a> <em>     * associated temporary disk file. Although this storage will be deleted</em>
<a name="448" href="#448">448</a> <em>     * automatically when the &lt;code>FileItem&lt;/code> instance is garbage</em>
<a name="449" href="#449">449</a> <em>     * collected, this method can be used to ensure that this is done at an</em>
<a name="450" href="#450">450</a> <em>     * earlier time, thus preserving system resources.</em>
<a name="451" href="#451">451</a> <em>     */</em>
<a name="452" href="#452">452</a>     <strong>public</strong> <strong>void</strong> delete() {
<a name="453" href="#453">453</a>         cachedContent = <strong>null</strong>;
<a name="454" href="#454">454</a>         File outputFile = getStoreLocation();
<a name="455" href="#455">455</a>         <strong>if</strong> (outputFile != <strong>null</strong> &amp;&amp; outputFile.exists()) {
<a name="456" href="#456">456</a>             outputFile.delete();
<a name="457" href="#457">457</a>         }
<a name="458" href="#458">458</a>     }
<a name="459" href="#459">459</a> 
<a name="460" href="#460">460</a> 
<a name="461" href="#461">461</a>     <em>/**<em>*</em></em>
<a name="462" href="#462">462</a> <em>     * Returns the name of the field in the multipart form corresponding to</em>
<a name="463" href="#463">463</a> <em>     * this file item.</em>
<a name="464" href="#464">464</a> <em>     *</em>
<a name="465" href="#465">465</a> <em>     * @return The name of the form field.</em>
<a name="466" href="#466">466</a> <em>     *</em>
<a name="467" href="#467">467</a> <em>     * @see #setFieldName(java.lang.String)</em>
<a name="468" href="#468">468</a> <em>     *</em>
<a name="469" href="#469">469</a> <em>     */</em>
<a name="470" href="#470">470</a>     <strong>public</strong> String getFieldName() {
<a name="471" href="#471">471</a>         <strong>return</strong> fieldName;
<a name="472" href="#472">472</a>     }
<a name="473" href="#473">473</a> 
<a name="474" href="#474">474</a> 
<a name="475" href="#475">475</a>     <em>/**<em>*</em></em>
<a name="476" href="#476">476</a> <em>     * Sets the field name used to reference this file item.</em>
<a name="477" href="#477">477</a> <em>     *</em>
<a name="478" href="#478">478</a> <em>     * @param fieldName The name of the form field.</em>
<a name="479" href="#479">479</a> <em>     *</em>
<a name="480" href="#480">480</a> <em>     * @see #getFieldName()</em>
<a name="481" href="#481">481</a> <em>     *</em>
<a name="482" href="#482">482</a> <em>     */</em>
<a name="483" href="#483">483</a>     <strong>public</strong> <strong>void</strong> setFieldName(String fieldName) {
<a name="484" href="#484">484</a>         <strong>this</strong>.fieldName = fieldName;
<a name="485" href="#485">485</a>     }
<a name="486" href="#486">486</a> 
<a name="487" href="#487">487</a> 
<a name="488" href="#488">488</a>     <em>/**<em>*</em></em>
<a name="489" href="#489">489</a> <em>     * Determines whether or not a &lt;code>FileItem&lt;/code> instance represents</em>
<a name="490" href="#490">490</a> <em>     * a simple form field.</em>
<a name="491" href="#491">491</a> <em>     *</em>
<a name="492" href="#492">492</a> <em>     * @return &lt;code>true&lt;/code> if the instance represents a simple form</em>
<a name="493" href="#493">493</a> <em>     *         field; &lt;code>false&lt;/code> if it represents an uploaded file.</em>
<a name="494" href="#494">494</a> <em>     *</em>
<a name="495" href="#495">495</a> <em>     * @see #setFormField(boolean)</em>
<a name="496" href="#496">496</a> <em>     *</em>
<a name="497" href="#497">497</a> <em>     */</em>
<a name="498" href="#498">498</a>     <strong>public</strong> <strong>boolean</strong> isFormField() {
<a name="499" href="#499">499</a>         <strong>return</strong> isFormField;
<a name="500" href="#500">500</a>     }
<a name="501" href="#501">501</a> 
<a name="502" href="#502">502</a> 
<a name="503" href="#503">503</a>     <em>/**<em>*</em></em>
<a name="504" href="#504">504</a> <em>     * Specifies whether or not a &lt;code>FileItem&lt;/code> instance represents</em>
<a name="505" href="#505">505</a> <em>     * a simple form field.</em>
<a name="506" href="#506">506</a> <em>     *</em>
<a name="507" href="#507">507</a> <em>     * @param state &lt;code>true&lt;/code> if the instance represents a simple form</em>
<a name="508" href="#508">508</a> <em>     *              field; &lt;code>false&lt;/code> if it represents an uploaded file.</em>
<a name="509" href="#509">509</a> <em>     *</em>
<a name="510" href="#510">510</a> <em>     * @see #isFormField()</em>
<a name="511" href="#511">511</a> <em>     *</em>
<a name="512" href="#512">512</a> <em>     */</em>
<a name="513" href="#513">513</a>     <strong>public</strong> <strong>void</strong> setFormField(<strong>boolean</strong> state) {
<a name="514" href="#514">514</a>         isFormField = state;
<a name="515" href="#515">515</a>     }
<a name="516" href="#516">516</a> 
<a name="517" href="#517">517</a> 
<a name="518" href="#518">518</a>     <em>/**<em>*</em></em>
<a name="519" href="#519">519</a> <em>     * Returns an {@link java.io.OutputStream OutputStream} that can</em>
<a name="520" href="#520">520</a> <em>     * be used for storing the contents of the file.</em>
<a name="521" href="#521">521</a> <em>     *</em>
<a name="522" href="#522">522</a> <em>     * @return An {@link java.io.OutputStream OutputStream} that can be used</em>