adaptiverevisitqueuelist.html

用JAVA编写的,在做实验的时候留下来的,本来想删的,但是传上来,大家分享吧

<a name="150" href="#150">150</a> <em>     * </em>
<a name="151" href="#151">151</a> <em>     * @param hostName The host's name </em>
<a name="152" href="#152">152</a> <em>     * @return an AdaptiveRevisitHostQueue for the specified host</em>
<a name="153" href="#153">153</a> <em>     */</em>
<a name="154" href="#154">154</a>     <strong>public</strong> <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> getHQ(String hostName) {
<a name="155" href="#155">155</a>         AdaptiveRevisitHostQueueWrapper wrapper =
<a name="156" href="#156">156</a>             ((AdaptiveRevisitHostQueueWrapper)hostQueues.get(hostName));
<a name="157" href="#157">157</a>         <strong>if</strong> (wrapper != <strong>null</strong>) {
<a name="158" href="#158">158</a>             <strong>return</strong> wrapper.hq;
<a name="159" href="#159">159</a>         }
<a name="160" href="#160">160</a>         <strong>return</strong> <strong>null</strong>;
<a name="161" href="#161">161</a>     }
<a name="162" href="#162">162</a>     
<a name="163" href="#163">163</a>     <em>/**<em>*</em></em>
<a name="164" href="#164">164</a> <em>     * Creates a new AdaptiveRevisitHostQueue.</em>
<a name="165" href="#165">165</a> <em>     * &lt;p></em>
<a name="166" href="#166">166</a> <em>     * If a HQ already existed for the specified hostName, the existing HQ</em>
<a name="167" href="#167">167</a> <em>     * is returned as it is. It's existing valence will &lt;i>not&lt;/i> be updated</em>
<a name="168" href="#168">168</a> <em>     * to reflect a different valence.</em>
<a name="169" href="#169">169</a> <em>     * </em>
<a name="170" href="#170">170</a> <em>     * @param hostName</em>
<a name="171" href="#171">171</a> <em>     * @param valence number of simultaneous connections allowed to this host</em>
<a name="172" href="#172">172</a> <em>     * @return the newly created HQ</em>
<a name="173" href="#173">173</a> <em>     * @throws IOException</em>
<a name="174" href="#174">174</a> <em>     */</em>
<a name="175" href="#175">175</a>     <strong>public</strong> <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> createHQ(String hostName, <strong>int</strong> valence)
<a name="176" href="#176">176</a>             throws IOException{
<a name="177" href="#177">177</a>         <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> hq =
<a name="178" href="#178">178</a>             (<a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a>)hostQueues.get(hostName);
<a name="179" href="#179">179</a>         <strong>if</strong>(hq == <strong>null</strong>) {
<a name="180" href="#180">180</a>             <em class="comment">// Ok, the HQ does not already exist. (Had to make sure) </em>
<a name="181" href="#181">181</a>             <em class="comment">// Create it, save it and return it.</em>
<a name="182" href="#182">182</a>             hq = <strong>new</strong> <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a>(hostName, env, catalog, valence);
<a name="183" href="#183">183</a>             hq.setOwner(<strong>this</strong>);
<a name="184" href="#184">184</a>             
<a name="185" href="#185">185</a>             <strong>try</strong>{
<a name="186" href="#186">186</a>                 DatabaseEntry keyEntry = <strong>new</strong> DatabaseEntry();
<a name="187" href="#187">187</a>                 DatabaseEntry dataEntry = <strong>new</strong> DatabaseEntry();
<a name="188" href="#188">188</a>                 keyBinding.objectToEntry(hostName,keyEntry);
<a name="189" href="#189">189</a>                 valueBinding.objectToEntry(<strong>new</strong> Integer(valence),dataEntry);
<a name="190" href="#190">190</a>                 hostNamesDB.put(<strong>null</strong>,keyEntry,dataEntry);
<a name="191" href="#191">191</a>                 AdaptiveRevisitHostQueueWrapper tmp =
<a name="192" href="#192">192</a>                     <strong>new</strong> AdaptiveRevisitHostQueueWrapper(hq);
<a name="193" href="#193">193</a>                 hostQueues.put(hostName,tmp);
<a name="194" href="#194">194</a>                 sortedHostQueues.add(tmp);
<a name="195" href="#195">195</a>             } <strong>catch</strong> (DatabaseException e) {
<a name="196" href="#196">196</a>                 <strong>throw</strong> convertDbException(e);
<a name="197" href="#197">197</a>             }
<a name="198" href="#198">198</a>         }
<a name="199" href="#199">199</a>         <strong>return</strong> hq;
<a name="200" href="#200">200</a>     }
<a name="201" href="#201">201</a>     
<a name="202" href="#202">202</a>     <strong>public</strong> <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> getTopHQ(){
<a name="203" href="#203">203</a>         AdaptiveRevisitHostQueueWrapper wrapper = 
<a name="204" href="#204">204</a>             (AdaptiveRevisitHostQueueWrapper)sortedHostQueues.first(); 
<a name="205" href="#205">205</a>         <strong>return</strong> wrapper.hq;
<a name="206" href="#206">206</a>     }
<a name="207" href="#207">207</a> 
<a name="208" href="#208">208</a>     <em>/**<em>*</em></em>
<a name="209" href="#209">209</a> <em>     * Returns the number of URIs in all the HQs in this list</em>
<a name="210" href="#210">210</a> <em>     * @return the number of URIs in all the HQs in this list</em>
<a name="211" href="#211">211</a> <em>     */</em>
<a name="212" href="#212">212</a>     <strong>public</strong> <strong>long</strong> getSize() {
<a name="213" href="#213">213</a>     	<strong>long</strong> size = 0;
<a name="214" href="#214">214</a>         <strong>for</strong> (Iterator it = sortedHostQueues.iterator(); it.hasNext();) {
<a name="215" href="#215">215</a>             <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> hq = ((AdaptiveRevisitHostQueueWrapper)it
<a name="216" href="#216">216</a>                     .next()).hq;
<a name="217" href="#217">217</a>             size += hq.getSize();
<a name="218" href="#218">218</a>         }
<a name="219" href="#219">219</a>         <strong>return</strong> size;
<a name="220" href="#220">220</a> 	}
<a name="221" href="#221">221</a>     
<a name="222" href="#222">222</a>     <em>/**<em>*</em></em>
<a name="223" href="#223">223</a> <em>     * Returns the average depth of all the HQs in this list</em>
<a name="224" href="#224">224</a> <em>     * @return the average depth of all the HQs in this list (rounded down)</em>
<a name="225" href="#225">225</a> <em>     */</em>
<a name="226" href="#226">226</a>     <strong>public</strong> <strong>long</strong> getAverageDepth() {
<a name="227" href="#227">227</a>     	<strong>long</strong> size = getSize();
<a name="228" href="#228">228</a>     	<strong>return</strong> size/hostQueues.size();
<a name="229" href="#229">229</a>     }
<a name="230" href="#230">230</a>     
<a name="231" href="#231">231</a>     <em>/**<em>*</em></em>
<a name="232" href="#232">232</a> <em>     * Returns the size of the largest (deepest) queue.</em>
<a name="233" href="#233">233</a> <em>     * @return the size of the largest (deepest) queue.</em>
<a name="234" href="#234">234</a> <em>     */</em>
<a name="235" href="#235">235</a>     <strong>public</strong> <strong>long</strong> getDeepestQueueSize(){
<a name="236" href="#236">236</a>     	<strong>long</strong> size = 0;
<a name="237" href="#237">237</a>         <strong>for</strong> (Iterator it = sortedHostQueues.iterator(); it.hasNext();) {
<a name="238" href="#238">238</a>             <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> hq = ((AdaptiveRevisitHostQueueWrapper)it
<a name="239" href="#239">239</a>                     .next()).hq;
<a name="240" href="#240">240</a>             <strong>if</strong>(hq.getSize() > size){
<a name="241" href="#241">241</a>             	size = hq.getSize();
<a name="242" href="#242">242</a>             }
<a name="243" href="#243">243</a>         }
<a name="244" href="#244">244</a>         <strong>return</strong> size;
<a name="245" href="#245">245</a>     }
<a name="246" href="#246">246</a>     
<a name="247" href="#247">247</a>     <em>/**<em>*</em></em>
<a name="248" href="#248">248</a> <em>     * Returns the congestion ratio.</em>
<a name="249" href="#249">249</a> <em>     * &lt;p></em>
<a name="250" href="#250">250</a> <em>     * The congestion ratio is equal to the total number of queues divided</em>
<a name="251" href="#251">251</a> <em>     * by the number of queues currently being processed or are snozzed (i.e. </em>
<a name="252" href="#252">252</a> <em>     * not ready). A congestion ratio of 1 indicates no congestion.</em>
<a name="253" href="#253">253</a> <em>     * @return the congestion ratio</em>
<a name="254" href="#254">254</a> <em>     */</em>
<a name="255" href="#255">255</a>     <strong>public</strong> <strong>float</strong> getCongestionRatio(){
<a name="256" href="#256">256</a>     	<strong>int</strong> readyQueues = 0;
<a name="257" href="#257">257</a>         <strong>for</strong> (Iterator it = sortedHostQueues.iterator(); it.hasNext();) {
<a name="258" href="#258">258</a>             <a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> hq = ((AdaptiveRevisitHostQueueWrapper)it
<a name="259" href="#259">259</a>                     .next()).hq;
<a name="260" href="#260">260</a>             <strong>if</strong>(hq.getState() == AdaptiveRevisitHostQueue.HQSTATE_READY){
<a name="261" href="#261">261</a>             	readyQueues++;
<a name="262" href="#262">262</a>             }
<a name="263" href="#263">263</a>         }
<a name="264" href="#264">264</a>         <strong>int</strong> totalQueues = hostQueues.size();
<a name="265" href="#265">265</a>         
<a name="266" href="#266">266</a>         <strong>return</strong> (<strong>float</strong>)(totalQueues) / (totalQueues-readyQueues);
<a name="267" href="#267">267</a>     }
<a name="268" href="#268">268</a>     
<a name="269" href="#269">269</a>     <em>/**<em>*</em></em>
<a name="270" href="#270">270</a> <em>     * This method reorders the host queues. Method is only called by the</em>
<a name="271" href="#271">271</a> <em>     * AdaptiveRevisitHostQueue that it 'owns' when their reported time of next</em>
<a name="272" href="#272">272</a> <em>     * ready is being updated.</em>
<a name="273" href="#273">273</a> <em>     * </em>
<a name="274" href="#274">274</a> <em>     * @param hq The calling HQ</em>
<a name="275" href="#275">275</a> <em>     */</em>
<a name="276" href="#276">276</a>     <strong>protected</strong> <strong>void</strong> reorder(<a href="../../../../org/archive/crawler/frontier/AdaptiveRevisitHostQueue.html">AdaptiveRevisitHostQueue</a> hq){
<a name="277" href="#277">277</a>         <em class="comment">// Find the wrapper</em>
<a name="278" href="#278">278</a>         AdaptiveRevisitHostQueueWrapper wrapper = 
<a name="279" href="#279">279</a>             (AdaptiveRevisitHostQueueWrapper)hostQueues.get(hq.getHostName());
<a name="280" href="#280">280</a>         
<a name="281" href="#281">281</a>         <strong>long</strong> newTime = hq.getNextReadyTime();
<a name="282" href="#282">282</a>         
<a name="283" href="#283">283</a>         <strong>if</strong>(newTime != wrapper.nextReadyTime){
<a name="284" href="#284">284</a>             <em class="comment">// Ok, the time has changed, move the queue around.</em>
<a name="285" href="#285">285</a>             <strong>if</strong> (logger.isLoggable(Level.FINER)) {
<a name="286" href="#286">286</a>                 logger.finer(<span class="string">"reorder("</span> + hq.getHostName() + <span class="string">") was "</span>
<a name="287" href="#287">287</a>                         + wrapper.nextReadyTime);
<a name="288" href="#288">288</a>             }
<a name="289" href="#289">289</a>             <em class="comment">// Remove it from the sorted list</em>
<a name="290" href="#290">290</a>             sortedHostQueues.remove(wrapper);
<a name="291" href="#291">291</a>             <em class="comment">// Update the time on the ref.</em>
<a name="292" href="#292">292</a>             wrapper.nextReadyTime = newTime;
<a name="293" href="#293">293</a>             <strong>if</strong> (logger.isLoggable(Level.FINER)) {
<a name="294" href="#294">294</a>                 logger.finer(<span class="string">"reorder("</span> + hq.getHostName() + <span class="string">") is "</span>
<a name="295" href="#295">295</a>                         + wrapper.nextReadyTime);
<a name="296" href="#296">296</a>             }
<a name="297" href="#297">297</a>             <em class="comment">// Readd to the list</em>
<a name="298" href="#298">298</a>             sortedHostQueues.add(wrapper);
<a name="299" href="#299">299</a>         }
<a name="300" href="#300">300</a>     }
<a name="301" href="#301">301</a>     
<a name="302" href="#302">302</a>     <em>/**<em>*</em></em>
<a name="303" href="#303">303</a> <em>     * The total number of URIs queued in all the HQs belonging to this list.</em>
<a name="304" href="#304">304</a> <em>     * </em>
<a name="305" href="#305">305</a> <em>     * @return total number of URIs queued in all the HQs belonging to this list.</em>
<a name="306" href="#306">306</a> <em>     */</em>
<a name="307" href="#307">307</a>     <strong>public</strong> <strong>long</strong> getUriCount(){