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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>MemLongFPSet xref</title><link type="text/css" rel="stylesheet" href="../../../../stylesheet.css" /></head><body><div id="overview"><a href="../../../../../apidocs/org/archive/util/fingerprint/MemLongFPSet.html">View Javadoc</a></div><pre><a name="1" href="#1">1</a> <em class="comment">/*<em class="comment"> MemLongSet</em></em><a name="2" href="#2">2</a> <em class="comment"> *</em><a name="3" href="#3">3</a> <em class="comment"> * $Id: MemLongFPSet.java,v 1.1 2005/05/06 02:49:01 stack-sf Exp $</em><a name="4" href="#4">4</a> <em class="comment"> *</em><a name="5" href="#5">5</a> <em class="comment"> * Created on Oct 19, 2003</em><a name="6" href="#6">6</a> <em class="comment"> *</em><a name="7" href="#7">7</a> <em class="comment"> * Copyright (C) 2003 Internet Archive.</em><a name="8" href="#8">8</a> <em class="comment"> *</em><a name="9" href="#9">9</a> <em class="comment"> * This file is part of the Heritrix web crawler (crawler.archive.org).</em><a name="10" href="#10">10</a> <em class="comment"> *</em><a name="11" href="#11">11</a> <em class="comment"> * Heritrix is free software; you can redistribute it and/or modify</em><a name="12" href="#12">12</a> <em class="comment"> * it under the terms of the GNU Lesser Public License as published by</em><a name="13" href="#13">13</a> <em class="comment"> * the Free Software Foundation; either version 2.1 of the License, or</em><a name="14" href="#14">14</a> <em class="comment"> * any later version.</em><a name="15" href="#15">15</a> <em class="comment"> *</em><a name="16" href="#16">16</a> <em class="comment"> * Heritrix is distributed in the hope that it will be useful,</em><a name="17" href="#17">17</a> <em class="comment"> * but WITHOUT ANY WARRANTY; without even the implied warranty of</em><a name="18" href="#18">18</a> <em class="comment"> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the</em><a name="19" href="#19">19</a> <em class="comment"> * GNU Lesser Public License for more details.</em><a name="20" href="#20">20</a> <em class="comment"> *</em><a name="21" href="#21">21</a> <em class="comment"> * You should have received a copy of the GNU Lesser Public License</em><a name="22" href="#22">22</a> <em class="comment"> * along with Heritrix; if not, write to the Free Software</em><a name="23" href="#23">23</a> <em class="comment"> * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA</em><a name="24" href="#24">24</a> <em class="comment"> */</em><a name="25" href="#25">25</a> <strong>package</strong> <a href="../../../../org/archive/util/fingerprint/package-summary.html">org.archive.util.fingerprint</a>;<a name="26" href="#26">26</a> <a name="27" href="#27">27</a> <strong>import</strong> java.io.Serializable;<a name="28" href="#28">28</a> <strong>import</strong> java.util.logging.Logger;<a name="29" href="#29">29</a> <a name="30" href="#30">30</a> <strong>import</strong> org.archive.util.AbstractLongFPSet;<a name="31" href="#31">31</a> <a name="32" href="#32">32</a> <em>/**<em>*</em></em><a name="33" href="#33">33</a> <em> * Open-addressing in-memory hash set for holding primitive long fingerprints.</em><a name="34" href="#34">34</a> <em> *</em><a name="35" href="#35">35</a> <em> * @author Gordon Mohr</em><a name="36" href="#36">36</a> <em> */</em><a name="37" href="#37">37</a> <strong>public</strong> <strong>class</strong> <a href="../../../../org/archive/util/fingerprint/MemLongFPSet.html">MemLongFPSet</a> <strong>extends</strong> <a href="../../../../org/archive/util/AbstractLongFPSet.html">AbstractLongFPSet</a><a name="38" href="#38">38</a> implements LongFPSet, Serializable {<a name="39" href="#39">39</a> <strong>private</strong> <strong>static</strong> Logger logger =<a name="40" href="#40">40</a> Logger.getLogger(MemLongFPSet.<strong>class</strong>.getName());<a name="41" href="#41">41</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_CAPACITY_POWER_OF_TWO = 10;<a name="42" href="#42">42</a> <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>float</strong> DEFAULT_LOAD_FACTOR = 0.75f;<a name="43" href="#43">43</a> <strong>protected</strong> byte[] slots;<a name="44" href="#44">44</a> <strong>protected</strong> <strong>long</strong>[] values;<a name="45" href="#45">45</a> <a name="46" href="#46">46</a> <strong>public</strong> <a href="../../../../org/archive/util/fingerprint/MemLongFPSet.html">MemLongFPSet</a>() {<a name="47" href="#47">47</a> <strong>this</strong>(DEFAULT_CAPACITY_POWER_OF_TWO, DEFAULT_LOAD_FACTOR);<a name="48" href="#48">48</a> }<a name="49" href="#49">49</a> <a name="50" href="#50">50</a> <em>/**<em>*</em></em><a name="51" href="#51">51</a> <em> * @param capacityPowerOfTwo The capacity as the exponent of a power of 2.</em><a name="52" href="#52">52</a> <em> * e.g if the capacity is <code>4</code> this means <code>2^^4</code></em><a name="53" href="#53">53</a> <em> * entries.</em><a name="54" href="#54">54</a> <em> * @param loadFactor The load factor as a fraction. This gives the amount</em><a name="55" href="#55">55</a> <em> * of free space to keep in the Set.</em><a name="56" href="#56">56</a> <em> */</em><a name="57" href="#57">57</a> <strong>public</strong> <a href="../../../../org/archive/util/fingerprint/MemLongFPSet.html">MemLongFPSet</a>(<strong>int</strong> capacityPowerOfTwo, <strong>float</strong> loadFactor) {<a name="58" href="#58">58</a> <strong>super</strong>(capacityPowerOfTwo, loadFactor);<a name="59" href="#59">59</a> slots = <strong>new</strong> byte[1 << capacityPowerOfTwo];<a name="60" href="#60">60</a> <strong>for</strong>(<strong>int</strong> i = 0; i < (1 << capacityPowerOfTwo); i++) {<a name="61" href="#61">61</a> slots[i] = EMPTY; <em class="comment">// flag value for unused</em><a name="62" href="#62">62</a> }<a name="63" href="#63">63</a> values = <strong>new</strong> <strong>long</strong>[1 << capacityPowerOfTwo];<a name="64" href="#64">64</a> }<a name="65" href="#65">65</a> <a name="66" href="#66">66</a> <strong>protected</strong> <strong>void</strong> setAt(<strong>long</strong> i, <strong>long</strong> val) {<a name="67" href="#67">67</a> slots[(<strong>int</strong>)i] = 1;<a name="68" href="#68">68</a> values[(<strong>int</strong>)i] = val;<a name="69" href="#69">69</a> }<a name="70" href="#70">70</a> <a name="71" href="#71">71</a> <strong>protected</strong> <strong>long</strong> getAt(<strong>long</strong> i) {<a name="72" href="#72">72</a> <strong>return</strong> values[(<strong>int</strong>)i];<a name="73" href="#73">73</a> }<a name="74" href="#74">74</a> <a name="75" href="#75">75</a> <strong>protected</strong> <strong>void</strong> makeSpace() {<a name="76" href="#76">76</a> grow();<a name="77" href="#77">77</a> }<a name="78" href="#78">78</a> <a name="79" href="#79">79</a> <strong>private</strong> <strong>void</strong> grow() {<a name="80" href="#80">80</a> <em class="comment">// Catastrophic event. Log its occurance.</em><a name="81" href="#81">81</a> logger.info(<span class="string">"Doubling fingerprinting slots to "</span><a name="82" href="#82">82</a> + (1 << <strong>this</strong>.capacityPowerOfTwo));<a name="83" href="#83">83</a> <strong>long</strong>[] oldValues = values;<a name="84" href="#84">84</a> byte[] oldSlots = slots;<a name="85" href="#85">85</a> capacityPowerOfTwo++;<a name="86" href="#86">86</a> values = <strong>new</strong> <strong>long</strong>[1 << capacityPowerOfTwo];<a name="87" href="#87">87</a> slots = <strong>new</strong> byte[1 << capacityPowerOfTwo];<a name="88" href="#88">88</a> <strong>for</strong>(<strong>int</strong> i = 0; i < (1 << capacityPowerOfTwo); i++) {<a name="89" href="#89">89</a> slots[i]=EMPTY; <em class="comment">// flag value for unused</em><a name="90" href="#90">90</a> }<a name="91" href="#91">91</a> count=0;<a name="92" href="#92">92</a> <strong>for</strong>(<strong>int</strong> i = 0; i< oldValues.length; i++) {<a name="93" href="#93">93</a> <strong>if</strong>(oldSlots[i]>=0) {<a name="94" href="#94">94</a> add(oldValues[i]);<a name="95" href="#95">95</a> }<a name="96" href="#96">96</a> }<a name="97" href="#97">97</a> }<a name="98" href="#98">98</a> <a name="99" href="#99">99</a> <strong>protected</strong> <strong>void</strong> relocate(<strong>long</strong> val, <strong>long</strong> oldIndex, <strong>long</strong> newIndex) {<a name="100" href="#100">100</a> values[(<strong>int</strong>)newIndex] = values[(<strong>int</strong>)oldIndex];<a name="101" href="#101">101</a> slots[(<strong>int</strong>)newIndex] = slots[(<strong>int</strong>)oldIndex];<a name="102" href="#102">102</a> slots[(<strong>int</strong>)oldIndex] = EMPTY;<a name="103" href="#103">103</a> }<a name="104" href="#104">104</a> <a name="105" href="#105">105</a> <strong>protected</strong> <strong>int</strong> getSlotState(<strong>long</strong> i) {<a name="106" href="#106">106</a> <strong>return</strong> slots[(<strong>int</strong>)i];<a name="107" href="#107">107</a> }<a name="108" href="#108">108</a> <a name="109" href="#109">109</a> <strong>protected</strong> <strong>void</strong> clearAt(<strong>long</strong> index) {<a name="110" href="#110">110</a> slots[(<strong>int</strong>)index]=EMPTY;<a name="111" href="#111">111</a> values[(<strong>int</strong>)index]=0;<a name="112" href="#112">112</a> }<a name="113" href="#113">113</a> <a name="114" href="#114">114</a> <strong>public</strong> <strong>boolean</strong> quickContains(<strong>long</strong> fp) {<a name="115" href="#115">115</a> <strong>return</strong> contains(fp);<a name="116" href="#116">116</a> }<a name="117" href="#117">117</a> }</pre><hr/><div id="footer">This page was automatically generated by <a href="http://maven.apache.org/">Maven</a></div></body></html>⌨️ 快捷键说明
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