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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"><head><meta http-equiv="content-type" content="text/html; charset=UTF-8" /><title>FetchHistoryProcessor xref</title><link type="text/css" rel="stylesheet" href="../../../../../stylesheet.css" /></head><body><div id="overview"><a href="../../../../../../apidocs/org/archive/crawler/processor/recrawl/FetchHistoryProcessor.html">View Javadoc</a></div><pre><a name="1" href="#1">1</a> <em class="comment">/*<em class="comment"> FetchHistoryProcessor</em></em><a name="2" href="#2">2</a> <em class="comment"> * </em><a name="3" href="#3">3</a> <em class="comment"> * Created on Feb 12, 2005</em><a name="4" href="#4">4</a> <em class="comment"> *</em><a name="5" href="#5">5</a> <em class="comment"> * Copyright (C) 2007 Internet Archive.</em><a name="6" href="#6">6</a> <em class="comment"> * </em><a name="7" href="#7">7</a> <em class="comment"> * This file is part of the Heritrix web crawler (crawler.archive.org).</em><a name="8" href="#8">8</a> <em class="comment"> * </em><a name="9" href="#9">9</a> <em class="comment"> * Heritrix is free software; you can redistribute it and/or modify</em><a name="10" href="#10">10</a> <em class="comment"> * it under the terms of the GNU Lesser Public License as published by</em><a name="11" href="#11">11</a> <em class="comment"> * the Free Software Foundation; either version 2.1 of the License, or</em><a name="12" href="#12">12</a> <em class="comment"> * any later version.</em><a name="13" href="#13">13</a> <em class="comment"> * </em><a name="14" href="#14">14</a> <em class="comment"> * Heritrix is distributed in the hope that it will be useful, </em><a name="15" href="#15">15</a> <em class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</em><a name="16" href="#16">16</a> <em class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</em><a name="17" href="#17">17</a> <em class="comment"> * GNU Lesser Public License for more details.</em><a name="18" href="#18">18</a> <em class="comment"> * </em><a name="19" href="#19">19</a> <em class="comment"> * You should have received a copy of the GNU Lesser Public License</em><a name="20" href="#20">20</a> <em class="comment"> * along with Heritrix; if not, write to the Free Software</em><a name="21" href="#21">21</a> <em class="comment"> * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA</em><a name="22" href="#22">22</a> <em class="comment"> */</em><a name="23" href="#23">23</a> <strong>package</strong> <a href="../../../../../org/archive/crawler/processor/recrawl/package-summary.html">org.archive.crawler.processor.recrawl</a>;<a name="24" href="#24">24</a> <a name="25" href="#25">25</a> <strong>import</strong> org.apache.commons.httpclient.Header;<a name="26" href="#26">26</a> <strong>import</strong> org.apache.commons.httpclient.HttpMethodBase;<a name="27" href="#27">27</a> <strong>import</strong> org.apache.commons.httpclient.HttpState;<a name="28" href="#28">28</a> <strong>import</strong> org.apache.commons.httpclient.HttpStatus;<a name="29" href="#29">29</a> <strong>import</strong> org.archive.crawler.datamodel.CoreAttributeConstants;<a name="30" href="#30">30</a> <strong>import</strong> org.archive.crawler.datamodel.CrawlURI;<a name="31" href="#31">31</a> <strong>import</strong> org.archive.crawler.framework.Processor;<a name="32" href="#32">32</a> <strong>import</strong> org.archive.crawler.settings.SimpleType;<a name="33" href="#33">33</a> <a name="34" href="#34">34</a> <strong>import</strong> st.ata.util.AList;<a name="35" href="#35">35</a> <strong>import</strong> st.ata.util.HashtableAList;<a name="36" href="#36">36</a> <a name="37" href="#37">37</a> <em>/**<em>*</em></em><a name="38" href="#38">38</a> <em> * Maintain a history of fetch information inside the CrawlURI's attributes. </em><a name="39" href="#39">39</a> <em> * </em><a name="40" href="#40">40</a> <em> * @author gojomo</em><a name="41" href="#41">41</a> <em> * @version $Date: 2006-09-25 20:19:54 +0000 (Mon, 25 Sep 2006) $, $Revision: 4654 $</em><a name="42" href="#42">42</a> <em> */</em><a name="43" href="#43">43</a> <strong>public</strong> <strong>class</strong> <a href="../../../../../org/archive/crawler/processor/recrawl/FetchHistoryProcessor.html">FetchHistoryProcessor</a> <strong>extends</strong> <a href="../../../../../org/archive/crawler/framework/Processor.html">Processor</a> implements <a href="../../../../../org/archive/crawler/datamodel/CoreAttributeConstants.html">CoreAttributeConstants</a> {<a name="44" href="#44">44</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>long</strong> serialVersionUID = 8476621038669163983L;<a name="45" href="#45">45</a> <a name="46" href="#46">46</a> <em>/**<em>* setting for desired history array length */</em></em><a name="47" href="#47">47</a> <strong>public</strong> <strong>static</strong> <strong>final</strong> String ATTR_HISTORY_LENGTH = <span class="string">"history-length"</span>;<a name="48" href="#48">48</a> <em>/**<em>* default history array length */</em> </em><a name="49" href="#49">49</a> <strong>public</strong> <strong>static</strong> <strong>final</strong> Integer DEFAULT_HISTORY_LENGTH = 2; <a name="50" href="#50">50</a> <a name="51" href="#51">51</a> <em>/**<em>*</em></em><a name="52" href="#52">52</a> <em> * Usual constructor</em><a name="53" href="#53">53</a> <em> * </em><a name="54" href="#54">54</a> <em> * @param name</em><a name="55" href="#55">55</a> <em> */</em><a name="56" href="#56">56</a> <strong>public</strong> <a href="../../../../../org/archive/crawler/processor/recrawl/FetchHistoryProcessor.html">FetchHistoryProcessor</a>(String name) {<a name="57" href="#57">57</a> <strong>super</strong>(name, <span class="string">"FetchHistoryProcessor. Maintain a history of fetch "</span> +<a name="58" href="#58">58</a> <span class="string">"information inside the CrawlURI's attributes.."</span>);<a name="59" href="#59">59</a> <a name="60" href="#60">60</a> addElementToDefinition(<strong>new</strong> <a href="../../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_HISTORY_LENGTH,<a name="61" href="#61">61</a> <span class="string">"Number of previous fetch entries to retain in the URI "</span> +<a name="62" href="#62">62</a> <span class="string">"history. The current fetch becomes a history entry at "</span> +<a name="63" href="#63">63</a> <span class="string">"this Processor step, so the smallest useful value is "</span> +<a name="64" href="#64">64</a> <span class="string">"'2' (including the current fetch). Default is '2'."</span>, <a name="65" href="#65">65</a> DEFAULT_HISTORY_LENGTH));<a name="66" href="#66">66</a> }<a name="67" href="#67">67</a> <a name="68" href="#68">68</a> @Override<a name="69" href="#69">69</a> <strong>protected</strong> <strong>void</strong> innerProcess(<a href="../../../../../org/archive/crawler/datamodel/CrawlURI.html">CrawlURI</a> curi) throws InterruptedException {<a name="70" href="#70">70</a> <a href="../../../../../st/ata/util/AList.html">AList</a> latestFetch = <strong>new</strong> <a href="../../../../../st/ata/util/HashtableAList.html">HashtableAList</a>();<a name="71" href="#71">71</a> <a name="72" href="#72">72</a> <em class="comment">// save status</em><a name="73" href="#73">73</a> latestFetch.putInt(A_STATUS,curi.getFetchStatus());<a name="74" href="#74">74</a> <em class="comment">// save fetch start time</em><a name="75" href="#75">75</a> latestFetch.putLong(A_FETCH_BEGAN_TIME,curi.getLong(A_FETCH_BEGAN_TIME));<a name="76" href="#76">76</a> <em class="comment">// save digest</em><a name="77" href="#77">77</a> String digest = curi.getContentDigestSchemeString();<a name="78" href="#78">78</a> <strong>if</strong>(digest!=<strong>null</strong>) {<a name="79" href="#79">79</a> latestFetch.putString(<a name="80" href="#80">80</a> A_CONTENT_DIGEST,digest);<a name="81" href="#81">81</a> }<a name="82" href="#82">82</a> <em class="comment">// save relevant HTTP headers, if available</em><a name="83" href="#83">83</a> <strong>if</strong>(curi.containsKey(A_HTTP_TRANSACTION)) {<a name="84" href="#84">84</a> <a href="../../../../../org/apache/commons/httpclient/HttpMethodBase.html">HttpMethodBase</a> method = <a name="85" href="#85">85</a> (<a href="../../../../../org/apache/commons/httpclient/HttpMethodBase.html">HttpMethodBase</a>) curi.getObject(A_HTTP_TRANSACTION);<a name="86" href="#86">86</a> saveHeader(A_ETAG_HEADER,method,latestFetch);<a name="87" href="#87">87</a> saveHeader(A_LAST_MODIFIED_HEADER,method,latestFetch);<a name="88" href="#88">88</a> <em class="comment">// save reference length (real or virtual)</em><a name="89" href="#89">89</a> <strong>long</strong> referenceLength; <a name="90" href="#90">90</a> <strong>if</strong>(curi.containsKey(A_REFERENCE_LENGTH) ) {<a name="91" href="#91">91</a> <em class="comment">// reuse previous length if available (see FetchHTTP#setSizes). </em><a name="92" href="#92">92</a> referenceLength = curi.getLong(A_REFERENCE_LENGTH);<a name="93" href="#93">93</a> } <strong>else</strong> {<a name="94" href="#94">94</a> <em class="comment">// normally, use content-length</em><a name="95" href="#95">95</a> referenceLength = curi.getContentLength();<a name="96" href="#96">96</a> }<a name="97" href="#97">97</a> latestFetch.putLong(A_REFERENCE_LENGTH,referenceLength);<a name="98" href="#98">98</a> }<a name="99" href="#99">99</a> <a name="100" href="#100">100</a> <em class="comment">// get or create proper-sized history array</em><a name="101" href="#101">101</a> <strong>int</strong> targetHistoryLength = <a name="102" href="#102">102</a> (Integer) getUncheckedAttribute(curi, ATTR_HISTORY_LENGTH);<a name="103" href="#103">103</a> <a href="../../../../../st/ata/util/AList.html">AList</a>[] history = <a name="104" href="#104">104</a> curi.getAList().containsKey(A_FETCH_HISTORY) <a name="105" href="#105">105</a> ? curi.getAList().getAListArray(A_FETCH_HISTORY) <a name="106" href="#106">106</a> : <strong>new</strong> <a href="../../../../../st/ata/util/AList.html">AList</a>[targetHistoryLength];<a name="107" href="#107">107</a> <strong>if</strong>(history.length != targetHistoryLength) {<a name="108" href="#108">108</a> <a href="../../../../../st/ata/util/AList.html">AList</a>[] <strong>new</strong>History = <strong>new</strong> <a href="../../../../../st/ata/util/AList.html">AList</a>[targetHistoryLength];<a name="109" href="#109">109</a> System.arraycopy(<a name="110" href="#110">110</a> history,0,<a name="111" href="#111">111</a> newHistory,0,<a name="112" href="#112">112</a> Math.min(history.length,newHistory.length));<a name="113" href="#113">113</a> history = newHistory; <a name="114" href="#114">114</a> }<a name="115" href="#115">115</a> <a name="116" href="#116">116</a> <em class="comment">// rotate all history entries up one slot, insert new at [0]</em><a name="117" href="#117">117</a> <strong>for</strong>(<strong>int</strong> i = history.length-1; i >0; i--) {<a name="118" href="#118">118</a> history[i] = history[i-1];<a name="119" href="#119">119</a> }<a name="120" href="#120">120</a> history[0]=latestFetch;<a name="121" href="#121">121</a> <a name="122" href="#122">122</a> curi.getAList().putAListArray(A_FETCH_HISTORY,history);<a name="123" href="#123">123</a> }<a name="124" href="#124">124</a> <a name="125" href="#125">125</a> <em>/**<em>*</em></em><a name="126" href="#126">126</a> <em> * Save a header from the given HTTP operation into the AList.</em><a name="127" href="#127">127</a> <em> * </em><a name="128" href="#128">128</a> <em> * @param name header name to save into history AList</em><a name="129" href="#129">129</a> <em> * @param method http operation containing headers</em><a name="130" href="#130">130</a> <em> * @param latestFetch AList to get header</em><a name="131" href="#131">131</a> <em> */</em><a name="132" href="#132">132</a> <strong>protected</strong> <strong>void</strong> saveHeader(String name, <a href="../../../../../org/apache/commons/httpclient/HttpMethodBase.html">HttpMethodBase</a> method, <a href="../../../../../st/ata/util/AList.html">AList</a> latestFetch) {<a name="133" href="#133">133</a> Header header = method.getResponseHeader(name);<a name="134" href="#134">134</a> <strong>if</strong>(header!=<strong>null</strong>) {<a name="135" href="#135">135</a> latestFetch.putString(name, header.getValue());<a name="136" href="#136">136</a> }<a name="137" href="#137">137</a> }<a name="138" href="#138">138</a> <a name="139" href="#139">139</a> @Override<a name="140" href="#140">140</a> <strong>protected</strong> <strong>void</strong> initialTasks() {<a name="141" href="#141">141</a> <em class="comment">// ensure history info persists across enqueues and recrawls</em><a name="142" href="#142">142</a> CrawlURI.addAlistPersistentMember(A_FETCH_HISTORY);<a name="143" href="#143">143</a> }<a name="144" href="#144">144</a> <a name="145" href="#145">145</a> <a name="146" href="#146">146</a> }</pre><hr/><div id="footer">This page was automatically generated by <a href="http://maven.apache.org/">Maven</a></div></body></html>?? 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