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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>DefaultIoEventSizeEstimator xref</title><link type="text/css" rel="stylesheet" href="../../../../../stylesheet.css" /></head><body><div id="overview"><a href="../../../../../../apidocs/org/apache/mina/filter/executor/DefaultIoEventSizeEstimator.html">View Javadoc</a></div><pre><a name="1" href="#1">1</a> <em class="jxr_comment">/*</em><a name="2" href="#2">2</a> <em class="jxr_comment"> * Licensed to the Apache Software Foundation (ASF) under one</em><a name="3" href="#3">3</a> <em class="jxr_comment"> * or more contributor license agreements. See the NOTICE file</em><a name="4" href="#4">4</a> <em class="jxr_comment"> * distributed with this work for additional information</em><a name="5" href="#5">5</a> <em class="jxr_comment"> * regarding copyright ownership. The ASF licenses this file</em><a name="6" href="#6">6</a> <em class="jxr_comment"> * to you under the Apache License, Version 2.0 (the</em><a name="7" href="#7">7</a> <em class="jxr_comment"> * "License"); you may not use this file except in compliance</em><a name="8" href="#8">8</a> <em class="jxr_comment"> * with the License. You may obtain a copy of the License at</em><a name="9" href="#9">9</a> <em class="jxr_comment"> *</em><a name="10" href="#10">10</a> <em class="jxr_comment"> * <a href="http://www.apache.org/licenses/LICENSE-2.0" target="alexandria_uri">http://www.apache.org/licenses/LICENSE-2.0</a></em><a name="11" href="#11">11</a> <em class="jxr_comment"> *</em><a name="12" href="#12">12</a> <em class="jxr_comment"> * Unless required by applicable law or agreed to in writing,</em><a name="13" href="#13">13</a> <em class="jxr_comment"> * software distributed under the License is distributed on an</em><a name="14" href="#14">14</a> <em class="jxr_comment"> * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY</em><a name="15" href="#15">15</a> <em class="jxr_comment"> * KIND, either express or implied. See the License for the</em><a name="16" href="#16">16</a> <em class="jxr_comment"> * specific language governing permissions and limitations</em><a name="17" href="#17">17</a> <em class="jxr_comment"> * under the License.</em><a name="18" href="#18">18</a> <em class="jxr_comment"> *</em><a name="19" href="#19">19</a> <em class="jxr_comment"> */</em><a name="20" href="#20">20</a> <strong class="jxr_keyword">package</strong> org.apache.mina.filter.executor;<a name="21" href="#21">21</a> <a name="22" href="#22">22</a> <strong class="jxr_keyword">import</strong> java.lang.reflect.Field;<a name="23" href="#23">23</a> <strong class="jxr_keyword">import</strong> java.lang.reflect.Modifier;<a name="24" href="#24">24</a> <strong class="jxr_keyword">import</strong> java.util.HashSet;<a name="25" href="#25">25</a> <strong class="jxr_keyword">import</strong> java.util.Set;<a name="26" href="#26">26</a> <strong class="jxr_keyword">import</strong> java.util.concurrent.ConcurrentHashMap;<a name="27" href="#27">27</a> <strong class="jxr_keyword">import</strong> java.util.concurrent.ConcurrentMap;<a name="28" href="#28">28</a> <a name="29" href="#29">29</a> <strong class="jxr_keyword">import</strong> org.apache.mina.common.IoBuffer;<a name="30" href="#30">30</a> <strong class="jxr_keyword">import</strong> org.apache.mina.common.IoEvent;<a name="31" href="#31">31</a> <a name="32" href="#32">32</a> <em class="jxr_javadoccomment">/**</em><a name="33" href="#33">33</a> <em class="jxr_javadoccomment"> * A default {@link IoEventSizeEstimator} implementation.</em><a name="34" href="#34">34</a> <em class="jxr_javadoccomment"> * <p></em><a name="35" href="#35">35</a> <em class="jxr_javadoccomment"> * <a href="<a href="http://martin.nobilitas.com/java/sizeof.html" target="alexandria_uri">http://martin.nobilitas.com/java/sizeof.html</a>">Martin's Java Notes</a></em><a name="36" href="#36">36</a> <em class="jxr_javadoccomment"> * was used for estimation. For unknown types, it inspects declaring fields of the</em><a name="37" href="#37">37</a> <em class="jxr_javadoccomment"> * class of the specified event and the parameter of the event. The size of unknown</em><a name="38" href="#38">38</a> <em class="jxr_javadoccomment"> * declaring fields are approximated to the specified <tt>averageSizePerField</tt></em><a name="39" href="#39">39</a> <em class="jxr_javadoccomment"> * (default: 64).</em><a name="40" href="#40">40</a> <em class="jxr_javadoccomment"> * <p></em><a name="41" href="#41">41</a> <em class="jxr_javadoccomment"> * All the estimated sizes of classes are cached for performance improvement.</em><a name="42" href="#42">42</a> <em class="jxr_javadoccomment"> * </em><a name="43" href="#43">43</a> <em class="jxr_javadoccomment"> * @author The Apache MINA Project (dev@mina.apache.org)</em><a name="44" href="#44">44</a> <em class="jxr_javadoccomment"> * @version $Rev: 595517 $, $Date: 2007-11-15 18:31:56 -0700 (Thu, 15 Nov 2007) $</em><a name="45" href="#45">45</a> <em class="jxr_javadoccomment"> */</em><a name="46" href="#46">46</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../org/apache/mina/filter/executor/DefaultIoEventSizeEstimator.html">DefaultIoEventSizeEstimator</a> implements <a href="../../../../../org/apache/mina/filter/executor/IoEventSizeEstimator.html">IoEventSizeEstimator</a> {<a name="47" href="#47">47</a> <a name="48" href="#48">48</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">final</strong> ConcurrentMap<Class<?>, Integer> <strong class="jxr_keyword">class</strong>2size = <strong class="jxr_keyword">new</strong> ConcurrentHashMap<Class<?>, Integer>();<a name="49" href="#49">49</a> <a name="50" href="#50">50</a> <strong class="jxr_keyword">public</strong> <a href="../../../../../org/apache/mina/filter/executor/DefaultIoEventSizeEstimator.html">DefaultIoEventSizeEstimator</a>() {<a name="51" href="#51">51</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">boolean</strong>.<strong class="jxr_keyword">class</strong>, 4); <em class="jxr_comment">// Probably an integer.</em><a name="52" href="#52">52</a> <strong class="jxr_keyword">class</strong>2size.put(byte.<strong class="jxr_keyword">class</strong>, 1);<a name="53" href="#53">53</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">char</strong>.<strong class="jxr_keyword">class</strong>, 2);<a name="54" href="#54">54</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">int</strong>.<strong class="jxr_keyword">class</strong>, 4);<a name="55" href="#55">55</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">short</strong>.<strong class="jxr_keyword">class</strong>, 2);<a name="56" href="#56">56</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">long</strong>.<strong class="jxr_keyword">class</strong>, 8);<a name="57" href="#57">57</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">float</strong>.<strong class="jxr_keyword">class</strong>, 4);<a name="58" href="#58">58</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">double</strong>.<strong class="jxr_keyword">class</strong>, 8);<a name="59" href="#59">59</a> <strong class="jxr_keyword">class</strong>2size.put(<strong class="jxr_keyword">void</strong>.<strong class="jxr_keyword">class</strong>, 0);<a name="60" href="#60">60</a> }<a name="61" href="#61">61</a> <a name="62" href="#62">62</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">int</strong> estimateSize(<a href="../../../../../org/apache/mina/common/IoEvent.html">IoEvent</a> event) {<a name="63" href="#63">63</a> <strong class="jxr_keyword">return</strong> estimateSize((Object) event) + estimateSize(event.getParameter());<a name="64" href="#64">64</a> }<a name="65" href="#65">65</a> <a name="66" href="#66">66</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">int</strong> estimateSize(Object message) {<a name="67" href="#67">67</a> <strong class="jxr_keyword">if</strong> (message == <strong class="jxr_keyword">null</strong>) {<a name="68" href="#68">68</a> <strong class="jxr_keyword">return</strong> 8;<a name="69" href="#69">69</a> }<a name="70" href="#70">70</a> <a name="71" href="#71">71</a> <strong class="jxr_keyword">int</strong> answer = 8 + estimateSize(message.getClass(), <strong class="jxr_keyword">null</strong>);<a name="72" href="#72">72</a> <a name="73" href="#73">73</a> <strong class="jxr_keyword">if</strong> (message instanceof IoBuffer) {<a name="74" href="#74">74</a> answer += ((IoBuffer) message).remaining();<a name="75" href="#75">75</a> } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (message instanceof CharSequence) {<a name="76" href="#76">76</a> answer += ((CharSequence) message).length() << 1;<a name="77" href="#77">77</a> } <strong class="jxr_keyword">else</strong> <strong class="jxr_keyword">if</strong> (message instanceof Iterable) {<a name="78" href="#78">78</a> <strong class="jxr_keyword">for</strong> (Object m: (Iterable<?>) message) {<a name="79" href="#79">79</a> answer += estimateSize(m);<a name="80" href="#80">80</a> }<a name="81" href="#81">81</a> }<a name="82" href="#82">82</a> <a name="83" href="#83">83</a> <strong class="jxr_keyword">return</strong> align(answer);<a name="84" href="#84">84</a> }<a name="85" href="#85">85</a> <a name="86" href="#86">86</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">int</strong> estimateSize(Class<?> clazz, Set<Class<?>> visitedClasses) {<a name="87" href="#87">87</a> Integer objectSize = <strong class="jxr_keyword">class</strong>2size.get(clazz);<a name="88" href="#88">88</a> <strong class="jxr_keyword">if</strong> (objectSize != <strong class="jxr_keyword">null</strong>) {<a name="89" href="#89">89</a> <strong class="jxr_keyword">return</strong> objectSize;<a name="90" href="#90">90</a> }<a name="91" href="#91">91</a> <a name="92" href="#92">92</a> <strong class="jxr_keyword">if</strong> (visitedClasses != <strong class="jxr_keyword">null</strong>) {<a name="93" href="#93">93</a> <strong class="jxr_keyword">if</strong> (visitedClasses.contains(clazz)) {<a name="94" href="#94">94</a> <strong class="jxr_keyword">return</strong> 0;<a name="95" href="#95">95</a> }<a name="96" href="#96">96</a> } <strong class="jxr_keyword">else</strong> {<a name="97" href="#97">97</a> visitedClasses = <strong class="jxr_keyword">new</strong> HashSet<Class<?>>();<a name="98" href="#98">98</a> }<a name="99" href="#99">99</a> <a name="100" href="#100">100</a> visitedClasses.add(clazz);<a name="101" href="#101">101</a> <a name="102" href="#102">102</a> <strong class="jxr_keyword">int</strong> answer = 8; <em class="jxr_comment">// Basic overhead.</em><a name="103" href="#103">103</a> <strong class="jxr_keyword">for</strong> (Class<?> c = clazz; c != <strong class="jxr_keyword">null</strong>; c = c.getSuperclass()) {<a name="104" href="#104">104</a> Field[] fields = c.getDeclaredFields();<a name="105" href="#105">105</a> <strong class="jxr_keyword">for</strong> (Field f: fields) {<a name="106" href="#106">106</a> <strong class="jxr_keyword">if</strong> ((f.getModifiers() & Modifier.STATIC) != 0) {<a name="107" href="#107">107</a> <em class="jxr_comment">// Ignore static fields.</em><a name="108" href="#108">108</a> <strong class="jxr_keyword">continue</strong>;<a name="109" href="#109">109</a> }<a name="110" href="#110">110</a> <a name="111" href="#111">111</a> answer += estimateSize(f.getType(), visitedClasses);<a name="112" href="#112">112</a> }<a name="113" href="#113">113</a> }<a name="114" href="#114">114</a> <a name="115" href="#115">115</a> visitedClasses.remove(clazz);<a name="116" href="#116">116</a> <a name="117" href="#117">117</a> <em class="jxr_comment">// Some alignment.</em><a name="118" href="#118">118</a> answer = align(answer);<a name="119" href="#119">119</a> <a name="120" href="#120">120</a> <em class="jxr_comment">// Put the final answer.</em><a name="121" href="#121">121</a> <strong class="jxr_keyword">class</strong>2size.putIfAbsent(clazz, answer);<a name="122" href="#122">122</a> <strong class="jxr_keyword">return</strong> answer;<a name="123" href="#123">123</a> }<a name="124" href="#124">124</a> <a name="125" href="#125">125</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">int</strong> align(<strong class="jxr_keyword">int</strong> size) {<a name="126" href="#126">126</a> <strong class="jxr_keyword">if</strong> (size % 8 != 0) {<a name="127" href="#127">127</a> size /= 8;<a name="128" href="#128">128</a> size ++;<a name="129" href="#129">129</a> size *= 8;<a name="130" href="#130">130</a> }<a name="131" href="#131">131</a> <strong class="jxr_keyword">return</strong> size;<a name="132" href="#132">132</a> }<a name="133" href="#133">133</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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