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<a name="124" href="#124">124</a> <em>     * at any time though before reading any of the arc record</em>
<a name="125" href="#125">125</a> <em>     * content is only time that it makes sense.</em>
<a name="126" href="#126">126</a> <em>     * </em>
<a name="127" href="#127">127</a> <em>     * &lt;p>After calling this method, you can call</em>
<a name="128" href="#128">128</a> <em>     * {@link #getHttpHeaders()} to get the read http header.</em>
<a name="129" href="#129">129</a> <em>     * </em>
<a name="130" href="#130">130</a> <em>     * @throws IOException</em>
<a name="131" href="#131">131</a> <em>     */</em>
<a name="132" href="#132">132</a>     <strong>public</strong> <strong>void</strong> skipHttpHeader() throws IOException {
<a name="133" href="#133">133</a>         <strong>if</strong> (<strong>this</strong>.httpHeaderStream != <strong>null</strong>) {
<a name="134" href="#134">134</a>             <em class="comment">// Empty the httpHeaderStream</em>
<a name="135" href="#135">135</a>             <strong>for</strong> (<strong>int</strong> available = <strong>this</strong>.httpHeaderStream.available();
<a name="136" href="#136">136</a>             		<strong>this</strong>.httpHeaderStream != <strong>null</strong> &amp;&amp;
<a name="137" href="#137">137</a>             			(available = <strong>this</strong>.httpHeaderStream.available()) > 0;) {
<a name="138" href="#138">138</a>                 <em class="comment">// We should be in this loop once only we should only do this</em>
<a name="139" href="#139">139</a>                 <em class="comment">// buffer allocation once.</em>
<a name="140" href="#140">140</a>                 byte [] buffer = <strong>new</strong> byte[available];
<a name="141" href="#141">141</a>                 <em class="comment">// The read nulls out httpHeaderStream when done with it so</em>
<a name="142" href="#142">142</a>                 <em class="comment">// need check for null in the loop control line.</em>
<a name="143" href="#143">143</a>                 read(buffer, 0, available);
<a name="144" href="#144">144</a>             }
<a name="145" href="#145">145</a>         }
<a name="146" href="#146">146</a>     }
<a name="147" href="#147">147</a>     
<a name="148" href="#148">148</a>     <strong>public</strong> <strong>void</strong> dumpHttpHeader() throws IOException {
<a name="149" href="#149">149</a> 		<strong>if</strong> (<strong>this</strong>.httpHeaderStream == <strong>null</strong>) {
<a name="150" href="#150">150</a> 			<strong>return</strong>;
<a name="151" href="#151">151</a> 		}
<a name="152" href="#152">152</a> 		<em class="comment">// Dump the httpHeaderStream to STDOUT</em>
<a name="153" href="#153">153</a> 		<strong>for</strong> (<strong>int</strong> available = <strong>this</strong>.httpHeaderStream.available();
<a name="154" href="#154">154</a> 			<strong>this</strong>.httpHeaderStream != <strong>null</strong>
<a name="155" href="#155">155</a> 				&amp;&amp; (available = <strong>this</strong>.httpHeaderStream.available()) > 0;) {
<a name="156" href="#156">156</a> 			<em class="comment">// We should be in this loop only once and should do this</em>
<a name="157" href="#157">157</a> 			<em class="comment">// buffer allocation once.</em>
<a name="158" href="#158">158</a> 			byte[] buffer = <strong>new</strong> byte[available];
<a name="159" href="#159">159</a> 			<em class="comment">// The read nulls out httpHeaderStream when done with it so</em>
<a name="160" href="#160">160</a> 			<em class="comment">// need check for null in the loop control line.</em>
<a name="161" href="#161">161</a> 			<strong>int</strong> read = read(buffer, 0, available);
<a name="162" href="#162">162</a> 			System.out.write(buffer, 0, read);
<a name="163" href="#163">163</a> 		}
<a name="164" href="#164">164</a> 	}
<a name="165" href="#165">165</a>     
<a name="166" href="#166">166</a>     <em>/**<em>*</em></em>
<a name="167" href="#167">167</a> <em>	 * Read http header if present. Technique borrowed from HttpClient HttpParse</em>
<a name="168" href="#168">168</a> <em>	 * class.</em>
<a name="169" href="#169">169</a> <em>	 * </em>
<a name="170" href="#170">170</a> <em>	 * @return ByteArrayInputStream with the http header in it or null if no</em>
<a name="171" href="#171">171</a> <em>	 *         http header.</em>
<a name="172" href="#172">172</a> <em>	 * @throws IOException</em>
<a name="173" href="#173">173</a> <em>	 */</em>
<a name="174" href="#174">174</a>     <strong>private</strong> InputStream readHttpHeader() throws IOException {
<a name="175" href="#175">175</a>         <em class="comment">// If judged a record that doesn't have an http header, return</em>
<a name="176" href="#176">176</a>         <em class="comment">// immediately.</em>
<a name="177" href="#177">177</a>         <strong>if</strong>(!getHeader().getUrl().startsWith(<span class="string">"http"</span>) ||
<a name="178" href="#178">178</a>             getHeader().getLength() &lt;= MIN_HTTP_HEADER_LENGTH) {
<a name="179" href="#179">179</a>             <strong>return</strong> <strong>null</strong>;
<a name="180" href="#180">180</a>         }
<a name="181" href="#181">181</a>         byte [] statusBytes = HttpParser.readRawLine(getIn());
<a name="182" href="#182">182</a>         <strong>int</strong> eolCharCount = getEolCharsCount(statusBytes);
<a name="183" href="#183">183</a>         <strong>if</strong> (eolCharCount &lt;= 0) {
<a name="184" href="#184">184</a>             <strong>throw</strong> <strong>new</strong> IOException(<span class="string">"Failed to read http status where one "</span> +
<a name="185" href="#185">185</a>                 <span class="string">" was expected: "</span> + <strong>new</strong> String(statusBytes));
<a name="186" href="#186">186</a>         }
<a name="187" href="#187">187</a>         String statusLine = EncodingUtil.getString(statusBytes, 0,
<a name="188" href="#188">188</a>             statusBytes.length - eolCharCount, ARCConstants.DEFAULT_ENCODING);
<a name="189" href="#189">189</a>         <strong>if</strong> ((statusLine == <strong>null</strong>) ||
<a name="190" href="#190">190</a>                 !StatusLine.startsWithHTTP(statusLine)) {
<a name="191" href="#191">191</a>             <strong>if</strong> (statusLine.startsWith(<span class="string">"DELETED"</span>)) {
<a name="192" href="#192">192</a>                 <em class="comment">// Some old ARCs have deleted records like following:</em>
<a name="193" href="#193">193</a>                 <em class="comment">// http://vireo.gatech.edu:80/ebt-bin/nph-dweb/dynaweb/SGI_Developer/SGITCL_PG/@Generic__BookTocView/11108%3Btd%3D2 130.207.168.42 19991010131803 text/html 29202</em>
<a name="194" href="#194">194</a>                 <em class="comment">// DELETED_TIME=20000425001133_DELETER=Kurt_REASON=alexalist</em>
<a name="195" href="#195">195</a>                 <em class="comment">// (follows ~29K spaces)</em>
<a name="196" href="#196">196</a>                 <em class="comment">// For now, throw a RecoverableIOException so if iterating over</em>
<a name="197" href="#197">197</a>                 <em class="comment">// records, we keep going.  TODO: Later make a legitimate</em>
<a name="198" href="#198">198</a>                 <em class="comment">// ARCRecord from the deleted record rather than throw</em>
<a name="199" href="#199">199</a>                 <em class="comment">// exception.</em>
<a name="200" href="#200">200</a>                 <strong>throw</strong> <strong>new</strong> DeletedARCRecordIOException(statusLine);
<a name="201" href="#201">201</a>             } <strong>else</strong> {
<a name="202" href="#202">202</a>                 <strong>throw</strong> <strong>new</strong> IOException(<span class="string">"Failed parse of http status line."</span>);
<a name="203" href="#203">203</a>             }
<a name="204" href="#204">204</a>         }
<a name="205" href="#205">205</a>         <strong>this</strong>.httpStatus = <strong>new</strong> StatusLine(statusLine);
<a name="206" href="#206">206</a>         
<a name="207" href="#207">207</a>         <em class="comment">// Save off all bytes read.  Keep them as bytes rather than</em>
<a name="208" href="#208">208</a>         <em class="comment">// convert to strings so we don't have to worry about encodings</em>
<a name="209" href="#209">209</a>         <em class="comment">// though this should never be a problem doing http headers since</em>
<a name="210" href="#210">210</a>         <em class="comment">// its all supposed to be ascii.</em>
<a name="211" href="#211">211</a>         ByteArrayOutputStream baos =
<a name="212" href="#212">212</a>             <strong>new</strong> ByteArrayOutputStream(statusBytes.length + 4 * 1024);
<a name="213" href="#213">213</a>         baos.write(statusBytes);
<a name="214" href="#214">214</a>         
<a name="215" href="#215">215</a>         <em class="comment">// Now read rest of the header lines looking for the separation</em>
<a name="216" href="#216">216</a>         <em class="comment">// between header and body.</em>
<a name="217" href="#217">217</a>         <strong>for</strong> (byte [] lineBytes = <strong>null</strong>; <strong>true</strong>;) {
<a name="218" href="#218">218</a>             lineBytes = HttpParser.readRawLine(getIn());
<a name="219" href="#219">219</a>             eolCharCount = getEolCharsCount(lineBytes);
<a name="220" href="#220">220</a>             <strong>if</strong> (eolCharCount &lt;= 0) {
<a name="221" href="#221">221</a>                 <strong>throw</strong> <strong>new</strong> IOException(<span class="string">"Failed reading http headers: "</span> +
<a name="222" href="#222">222</a>                     ((lineBytes != <strong>null</strong>)? <strong>new</strong> String(lineBytes): <strong>null</strong>));
<a name="223" href="#223">223</a>             }
<a name="224" href="#224">224</a>             <em class="comment">// Save the bytes read.</em>
<a name="225" href="#225">225</a>             baos.write(lineBytes);
<a name="226" href="#226">226</a>             <strong>if</strong> ((lineBytes.length - eolCharCount) &lt;= 0) {
<a name="227" href="#227">227</a>                 <em class="comment">// We've finished reading the http header.</em>
<a name="228" href="#228">228</a>                 <strong>break</strong>;
<a name="229" href="#229">229</a>             }
<a name="230" href="#230">230</a>         }
<a name="231" href="#231">231</a>         
<a name="232" href="#232">232</a>         byte [] headerBytes = baos.toByteArray();
<a name="233" href="#233">233</a>         <em class="comment">// Save off where body starts.</em>
<a name="234" href="#234">234</a>         <strong>this</strong>.getMetaData().setContentBegin(headerBytes.length);
<a name="235" href="#235">235</a>         ByteArrayInputStream bais =
<a name="236" href="#236">236</a>             <strong>new</strong> ByteArrayInputStream(headerBytes);
<a name="237" href="#237">237</a>         <strong>if</strong> (!bais.markSupported()) {
<a name="238" href="#238">238</a>             <strong>throw</strong> <strong>new</strong> IOException(<span class="string">"ByteArrayInputStream does not support mark"</span>);
<a name="239" href="#239">239</a>         }
<a name="240" href="#240">240</a>         bais.mark(headerBytes.length);
<a name="241" href="#241">241</a>         <em class="comment">// Read the status line.  Don't let it into the parseHeaders function.</em>
<a name="242" href="#242">242</a>         <em class="comment">// It doesn't know what to do with it.</em>
<a name="243" href="#243">243</a>         bais.read(statusBytes, 0, statusBytes.length);
<a name="244" href="#244">244</a>         <strong>this</strong>.httpHeaders = HttpParser.parseHeaders(bais,
<a name="245" href="#245">245</a>             ARCConstants.DEFAULT_ENCODING);
<a name="246" href="#246">246</a>         <strong>this</strong>.getMetaData().setStatusCode(Integer.toString(getStatusCode()));
<a name="247" href="#247">247</a>         bais.reset();
<a name="248" href="#248">248</a>         <strong>return</strong> bais;
<a name="249" href="#249">249</a>     }
<a name="250" href="#250">250</a>     
<a name="251" href="#251">251</a>     <strong>private</strong> <strong>static</strong> <strong>class</strong> DeletedARCRecordIOException
<a name="252" href="#252">252</a>     <strong>extends</strong> <a href="../../../../org/archive/io/RecoverableIOException.html">RecoverableIOException</a> {
<a name="253" href="#253">253</a>         <strong>public</strong> DeletedARCRecordIOException(<strong>final</strong> String reason) {
<a name="254" href="#254">254</a>             <strong>super</strong>(reason);
<a name="255" href="#255">255</a>         }