diskfileitem.html

java 的上传功能很强大的实施上述事实上说是

<a name="128" href="#128">128</a> <em class="jxr_javadoccomment">     */</em>
<a name="129" href="#129">129</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">boolean</strong> isFormField;
<a name="130" href="#130">130</a> 
<a name="131" href="#131">131</a> 
<a name="132" href="#132">132</a>     <em class="jxr_javadoccomment">/**</em>
<a name="133" href="#133">133</a> <em class="jxr_javadoccomment">     * The original filename in the user's filesystem.</em>
<a name="134" href="#134">134</a> <em class="jxr_javadoccomment">     */</em>
<a name="135" href="#135">135</a>     <strong class="jxr_keyword">private</strong> String fileName;
<a name="136" href="#136">136</a> 
<a name="137" href="#137">137</a> 
<a name="138" href="#138">138</a>     <em class="jxr_javadoccomment">/**</em>
<a name="139" href="#139">139</a> <em class="jxr_javadoccomment">     * The size of the item, in bytes. This is used to cache the size when a</em>
<a name="140" href="#140">140</a> <em class="jxr_javadoccomment">     * file item is moved from its original location.</em>
<a name="141" href="#141">141</a> <em class="jxr_javadoccomment">     */</em>
<a name="142" href="#142">142</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">long</strong> size = -1;
<a name="143" href="#143">143</a> 
<a name="144" href="#144">144</a> 
<a name="145" href="#145">145</a>     <em class="jxr_javadoccomment">/**</em>
<a name="146" href="#146">146</a> <em class="jxr_javadoccomment">     * The threshold above which uploads will be stored on disk.</em>
<a name="147" href="#147">147</a> <em class="jxr_javadoccomment">     */</em>
<a name="148" href="#148">148</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">int</strong> sizeThreshold;
<a name="149" href="#149">149</a> 
<a name="150" href="#150">150</a> 
<a name="151" href="#151">151</a>     <em class="jxr_javadoccomment">/**</em>
<a name="152" href="#152">152</a> <em class="jxr_javadoccomment">     * The directory in which uploaded files will be stored, if stored on disk.</em>
<a name="153" href="#153">153</a> <em class="jxr_javadoccomment">     */</em>
<a name="154" href="#154">154</a>     <strong class="jxr_keyword">private</strong> File repository;
<a name="155" href="#155">155</a> 
<a name="156" href="#156">156</a> 
<a name="157" href="#157">157</a>     <em class="jxr_javadoccomment">/**</em>
<a name="158" href="#158">158</a> <em class="jxr_javadoccomment">     * Cached contents of the file.</em>
<a name="159" href="#159">159</a> <em class="jxr_javadoccomment">     */</em>
<a name="160" href="#160">160</a>     <strong class="jxr_keyword">private</strong> byte[] cachedContent;
<a name="161" href="#161">161</a> 
<a name="162" href="#162">162</a> 
<a name="163" href="#163">163</a>     <em class="jxr_javadoccomment">/**</em>
<a name="164" href="#164">164</a> <em class="jxr_javadoccomment">     * Output stream for this item.</em>
<a name="165" href="#165">165</a> <em class="jxr_javadoccomment">     */</em>
<a name="166" href="#166">166</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">transient</strong> DeferredFileOutputStream dfos;
<a name="167" href="#167">167</a> 
<a name="168" href="#168">168</a>     <em class="jxr_javadoccomment">/**</em>
<a name="169" href="#169">169</a> <em class="jxr_javadoccomment">     * The temporary file to use.</em>
<a name="170" href="#170">170</a> <em class="jxr_javadoccomment">     */</em>
<a name="171" href="#171">171</a>     <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">transient</strong> File tempFile;
<a name="172" href="#172">172</a> 
<a name="173" href="#173">173</a>     <em class="jxr_javadoccomment">/**</em>
<a name="174" href="#174">174</a> <em class="jxr_javadoccomment">     * File to allow for serialization of the content of this item.</em>
<a name="175" href="#175">175</a> <em class="jxr_javadoccomment">     */</em>
<a name="176" href="#176">176</a>     <strong class="jxr_keyword">private</strong> File dfosFile;
<a name="177" href="#177">177</a> 
<a name="178" href="#178">178</a>     <em class="jxr_javadoccomment">/**</em>
<a name="179" href="#179">179</a> <em class="jxr_javadoccomment">     * The file items headers.</em>
<a name="180" href="#180">180</a> <em class="jxr_javadoccomment">     */</em>
<a name="181" href="#181">181</a>     <strong class="jxr_keyword">private</strong> <a href="../../../../../org/apache/commons/fileupload/FileItemHeaders.html">FileItemHeaders</a> headers;
<a name="182" href="#182">182</a> 
<a name="183" href="#183">183</a>     <em class="jxr_comment">// ----------------------------------------------------------- Constructors</em>
<a name="184" href="#184">184</a> 
<a name="185" href="#185">185</a> 
<a name="186" href="#186">186</a>     <em class="jxr_javadoccomment">/**</em>
<a name="187" href="#187">187</a> <em class="jxr_javadoccomment">     * Constructs a new &lt;code&gt;DiskFileItem&lt;/code&gt; instance.</em>
<a name="188" href="#188">188</a> <em class="jxr_javadoccomment">     *</em>
<a name="189" href="#189">189</a> <em class="jxr_javadoccomment">     * @param fieldName     The name of the form field.</em>
<a name="190" href="#190">190</a> <em class="jxr_javadoccomment">     * @param contentType   The content type passed by the browser or</em>
<a name="191" href="#191">191</a> <em class="jxr_javadoccomment">     *                      &lt;code&gt;null&lt;/code&gt; if not specified.</em>
<a name="192" href="#192">192</a> <em class="jxr_javadoccomment">     * @param isFormField   Whether or not this item is a plain form field, as</em>
<a name="193" href="#193">193</a> <em class="jxr_javadoccomment">     *                      opposed to a file upload.</em>
<a name="194" href="#194">194</a> <em class="jxr_javadoccomment">     * @param fileName      The original filename in the user's filesystem, or</em>
<a name="195" href="#195">195</a> <em class="jxr_javadoccomment">     *                      &lt;code&gt;null&lt;/code&gt; if not specified.</em>
<a name="196" href="#196">196</a> <em class="jxr_javadoccomment">     * @param sizeThreshold The threshold, in bytes, below which items will be</em>
<a name="197" href="#197">197</a> <em class="jxr_javadoccomment">     *                      retained in memory and above which they will be</em>
<a name="198" href="#198">198</a> <em class="jxr_javadoccomment">     *                      stored as a file.</em>
<a name="199" href="#199">199</a> <em class="jxr_javadoccomment">     * @param repository    The data repository, which is the directory in</em>
<a name="200" href="#200">200</a> <em class="jxr_javadoccomment">     *                      which files will be created, should the item size</em>
<a name="201" href="#201">201</a> <em class="jxr_javadoccomment">     *                      exceed the threshold.</em>
<a name="202" href="#202">202</a> <em class="jxr_javadoccomment">     */</em>
<a name="203" href="#203">203</a>     <strong class="jxr_keyword">public</strong> <a href="../../../../../org/apache/commons/fileupload/disk/DiskFileItem.html">DiskFileItem</a>(String fieldName,
<a name="204" href="#204">204</a>             String contentType, <strong class="jxr_keyword">boolean</strong> isFormField, String fileName,
<a name="205" href="#205">205</a>             <strong class="jxr_keyword">int</strong> sizeThreshold, File repository) {
<a name="206" href="#206">206</a>         <strong class="jxr_keyword">this</strong>.fieldName = fieldName;
<a name="207" href="#207">207</a>         <strong class="jxr_keyword">this</strong>.contentType = contentType;
<a name="208" href="#208">208</a>         <strong class="jxr_keyword">this</strong>.isFormField = isFormField;
<a name="209" href="#209">209</a>         <strong class="jxr_keyword">this</strong>.fileName = fileName;
<a name="210" href="#210">210</a>         <strong class="jxr_keyword">this</strong>.sizeThreshold = sizeThreshold;
<a name="211" href="#211">211</a>         <strong class="jxr_keyword">this</strong>.repository = repository;
<a name="212" href="#212">212</a>     }
<a name="213" href="#213">213</a> 
<a name="214" href="#214">214</a> 
<a name="215" href="#215">215</a>     <em class="jxr_comment">// ------------------------------- Methods from javax.activation.DataSource</em>
<a name="216" href="#216">216</a> 
<a name="217" href="#217">217</a> 
<a name="218" href="#218">218</a>     <em class="jxr_javadoccomment">/**</em>
<a name="219" href="#219">219</a> <em class="jxr_javadoccomment">     * Returns an {@link java.io.InputStream InputStream} that can be</em>
<a name="220" href="#220">220</a> <em class="jxr_javadoccomment">     * used to retrieve the contents of the file.</em>
<a name="221" href="#221">221</a> <em class="jxr_javadoccomment">     *</em>
<a name="222" href="#222">222</a> <em class="jxr_javadoccomment">     * @return An {@link java.io.InputStream InputStream} that can be</em>
<a name="223" href="#223">223</a> <em class="jxr_javadoccomment">     *         used to retrieve the contents of the file.</em>
<a name="224" href="#224">224</a> <em class="jxr_javadoccomment">     *</em>
<a name="225" href="#225">225</a> <em class="jxr_javadoccomment">     * @throws IOException if an error occurs.</em>
<a name="226" href="#226">226</a> <em class="jxr_javadoccomment">     */</em>
<a name="227" href="#227">227</a>     <strong class="jxr_keyword">public</strong> InputStream getInputStream()
<a name="228" href="#228">228</a>         <strong class="jxr_keyword">throws</strong> IOException {
<a name="229" href="#229">229</a>         <strong class="jxr_keyword">if</strong> (!isInMemory()) {
<a name="230" href="#230">230</a>             <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">new</strong> FileInputStream(dfos.getFile());
<a name="231" href="#231">231</a>         }
<a name="232" href="#232">232</a> 
<a name="233" href="#233">233</a>         <strong class="jxr_keyword">if</strong> (cachedContent == <strong class="jxr_keyword">null</strong>) {
<a name="234" href="#234">234</a>             cachedContent = dfos.getData();
<a name="235" href="#235">235</a>         }
<a name="236" href="#236">236</a>         <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">new</strong> ByteArrayInputStream(cachedContent);
<a name="237" href="#237">237</a>     }
<a name="238" href="#238">238</a> 
<a name="239" href="#239">239</a> 
<a name="240" href="#240">240</a>     <em class="jxr_javadoccomment">/**</em>
<a name="241" href="#241">241</a> <em class="jxr_javadoccomment">     * Returns the content type passed by the agent or &lt;code&gt;null&lt;/code&gt; if</em>
<a name="242" href="#242">242</a> <em class="jxr_javadoccomment">     * not defined.</em>
<a name="243" href="#243">243</a> <em class="jxr_javadoccomment">     *</em>
<a name="244" href="#244">244</a> <em class="jxr_javadoccomment">     * @return The content type passed by the agent or &lt;code&gt;null&lt;/code&gt; if</em>
<a name="245" href="#245">245</a> <em class="jxr_javadoccomment">     *         not defined.</em>
<a name="246" href="#246">246</a> <em class="jxr_javadoccomment">     */</em>
<a name="247" href="#247">247</a>     <strong class="jxr_keyword">public</strong> String getContentType() {
<a name="248" href="#248">248</a>         <strong class="jxr_keyword">return</strong> contentType;
<a name="249" href="#249">249</a>     }
<a name="250" href="#250">250</a> 
<a name="251" href="#251">251</a> 
<a name="252" href="#252">252</a>     <em class="jxr_javadoccomment">/**</em>
<a name="253" href="#253">253</a> <em class="jxr_javadoccomment">     * Returns the content charset passed by the agent or &lt;code&gt;null&lt;/code&gt; if</em>
<a name="254" href="#254">254</a> <em class="jxr_javadoccomment">     * not defined.</em>
<a name="255" href="#255">255</a> <em class="jxr_javadoccomment">     *</em>
<a name="256" href="#256">256</a> <em class="jxr_javadoccomment">     * @return The content charset passed by the agent or &lt;code&gt;null&lt;/code&gt; if</em>
<a name="257" href="#257">257</a> <em class="jxr_javadoccomment">     *         not defined.</em>
<a name="258" href="#258">258</a> <em class="jxr_javadoccomment">     */</em>
<a name="259" href="#259">259</a>     <strong class="jxr_keyword">public</strong> String getCharSet() {
<a name="260" href="#260">260</a>         <a href="../../../../../org/apache/commons/fileupload/ParameterParser.html">ParameterParser</a> parser = <strong class="jxr_keyword">new</strong> <a href="../../../../../org/apache/commons/fileupload/ParameterParser.html">ParameterParser</a>();
<a name="261" href="#261">261</a>         parser.setLowerCaseNames(<strong class="jxr_keyword">true</strong>);
<a name="262" href="#262">262</a>         <em class="jxr_comment">// Parameter parser can handle null input</em>
<a name="263" href="#263">263</a>         Map params = parser.parse(getContentType(), ';');
<a name="264" href="#264">264</a>         <strong class="jxr_keyword">return</strong> (String) params.get(<span class="jxr_string">"charset"</span>);