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<div id="overview"><a href="../../../../../../../apidocs/org/apache/logging/log4j/core/helpers/UUIDUtil.html">View Javadoc</a></div><pre>
<a class="jxr_linenumber" name="1" href="#1">1</a> <em class="jxr_comment">/*</em>
<a class="jxr_linenumber" name="2" href="#2">2</a> <em class="jxr_comment"> * Licensed to the Apache Software Foundation (ASF) under one or more</em>
<a class="jxr_linenumber" name="3" href="#3">3</a> <em class="jxr_comment"> * contributor license agreements. See the NOTICE file distributed with</em>
<a class="jxr_linenumber" name="4" href="#4">4</a> <em class="jxr_comment"> * this work for additional information regarding copyright ownership.</em>
<a class="jxr_linenumber" name="5" href="#5">5</a> <em class="jxr_comment"> * The ASF licenses this file to You under the Apache license, Version 2.0</em>
<a class="jxr_linenumber" name="6" href="#6">6</a> <em class="jxr_comment"> * (the "License"); you may not use this file except in compliance with</em>
<a class="jxr_linenumber" name="7" href="#7">7</a> <em class="jxr_comment"> * the License. You may obtain a copy of the License at</em>
<a class="jxr_linenumber" name="8" href="#8">8</a> <em class="jxr_comment"> *</em>
<a class="jxr_linenumber" name="9" href="#9">9</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 class="jxr_linenumber" name="10" href="#10">10</a> <em class="jxr_comment"> *</em>
<a class="jxr_linenumber" name="11" href="#11">11</a> <em class="jxr_comment"> * Unless required by applicable law or agreed to in writing, software</em>
<a class="jxr_linenumber" name="12" href="#12">12</a> <em class="jxr_comment"> * distributed under the License is distributed on an "AS IS" BASIS,</em>
<a class="jxr_linenumber" name="13" href="#13">13</a> <em class="jxr_comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</em>
<a class="jxr_linenumber" name="14" href="#14">14</a> <em class="jxr_comment"> * See the license for the specific language governing permissions and</em>
<a class="jxr_linenumber" name="15" href="#15">15</a> <em class="jxr_comment"> * limitations under the license.</em>
<a class="jxr_linenumber" name="16" href="#16">16</a> <em class="jxr_comment"> */</em>
<a class="jxr_linenumber" name="17" href="#17">17</a> <strong class="jxr_keyword">package</strong> org.apache.logging.log4j.core.helpers;
<a class="jxr_linenumber" name="18" href="#18">18</a>
<a class="jxr_linenumber" name="19" href="#19">19</a> <strong class="jxr_keyword">import</strong> java.lang.reflect.Method;
<a class="jxr_linenumber" name="20" href="#20">20</a> <strong class="jxr_keyword">import</strong> java.net.InetAddress;
<a class="jxr_linenumber" name="21" href="#21">21</a> <strong class="jxr_keyword">import</strong> java.net.NetworkInterface;
<a class="jxr_linenumber" name="22" href="#22">22</a> <strong class="jxr_keyword">import</strong> java.net.UnknownHostException;
<a class="jxr_linenumber" name="23" href="#23">23</a> <strong class="jxr_keyword">import</strong> java.nio.ByteBuffer;
<a class="jxr_linenumber" name="24" href="#24">24</a> <strong class="jxr_keyword">import</strong> java.security.SecureRandom;
<a class="jxr_linenumber" name="25" href="#25">25</a> <strong class="jxr_keyword">import</strong> java.util.Enumeration;
<a class="jxr_linenumber" name="26" href="#26">26</a> <strong class="jxr_keyword">import</strong> java.util.Random;
<a class="jxr_linenumber" name="27" href="#27">27</a> <strong class="jxr_keyword">import</strong> java.util.UUID;
<a class="jxr_linenumber" name="28" href="#28">28</a> <strong class="jxr_keyword">import</strong> java.util.concurrent.atomic.AtomicInteger;
<a class="jxr_linenumber" name="29" href="#29">29</a>
<a class="jxr_linenumber" name="30" href="#30">30</a> <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="31" href="#31">31</a> <em class="jxr_javadoccomment"> * Generates a unique id. The generated UUID will be unique for approximately 8,925 years so long as</em>
<a class="jxr_linenumber" name="32" href="#32">32</a> <em class="jxr_javadoccomment"> * less than 4095 ids are generated per millisecond on the same device (as identified by its MAC adddress).</em>
<a class="jxr_linenumber" name="33" href="#33">33</a> <em class="jxr_javadoccomment"> */</em>
<a class="jxr_linenumber" name="34" href="#34">34</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">class</strong> <a href="../../../../../../org/apache/logging/log4j/core/helpers/UUIDUtil.html">UUIDUtil</a> {
<a class="jxr_linenumber" name="35" href="#35">35</a> <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="36" href="#36">36</a> <em class="jxr_javadoccomment"> * System property that may be used to seed the uuid generation with an integer value.</em>
<a class="jxr_linenumber" name="37" href="#37">37</a> <em class="jxr_javadoccomment"> */</em>
<a class="jxr_linenumber" name="38" href="#38">38</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> String UUID_SEQUENCE = <span class="jxr_string">"org.apache.logging.log4j.uuidSequence"</span>;
<a class="jxr_linenumber" name="39" href="#39">39</a>
<a class="jxr_linenumber" name="40" href="#40">40</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> String ASSIGNED_SEQUENCES = <span class="jxr_string">"org.apache.logging.log4j.assignedSequences"</span>;
<a class="jxr_linenumber" name="41" href="#41">41</a>
<a class="jxr_linenumber" name="42" href="#42">42</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> AtomicInteger count = <strong class="jxr_keyword">new</strong> AtomicInteger(0);
<a class="jxr_linenumber" name="43" href="#43">43</a>
<a class="jxr_linenumber" name="44" href="#44">44</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">long</strong> TYPE1 = 0x1000L;
<a class="jxr_linenumber" name="45" href="#45">45</a>
<a class="jxr_linenumber" name="46" href="#46">46</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> byte VARIANT = (byte) 0x80;
<a class="jxr_linenumber" name="47" href="#47">47</a>
<a class="jxr_linenumber" name="48" href="#48">48</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> SEQUENCE_MASK = 0x3FFF;
<a class="jxr_linenumber" name="49" href="#49">49</a>
<a class="jxr_linenumber" name="50" href="#50">50</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">long</strong> NUM_100NS_INTERVALS_SINCE_UUID_EPOCH = 0x01b21dd213814000L;
<a class="jxr_linenumber" name="51" href="#51">51</a>
<a class="jxr_linenumber" name="52" href="#52">52</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">long</strong> uuidSequence = Long.getLong(UUID_SEQUENCE, 0);
<a class="jxr_linenumber" name="53" href="#53">53</a>
<a class="jxr_linenumber" name="54" href="#54">54</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">long</strong> least;
<a class="jxr_linenumber" name="55" href="#55">55</a>
<a class="jxr_linenumber" name="56" href="#56">56</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">long</strong> LOW_MASK = 0xffffffffL;
<a class="jxr_linenumber" name="57" href="#57">57</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">long</strong> MID_MASK = 0xffff00000000L;
<a class="jxr_linenumber" name="58" href="#58">58</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">long</strong> HIGH_MASK = 0xfff000000000000L;
<a class="jxr_linenumber" name="59" href="#59">59</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> NODE_SIZE = 8;
<a class="jxr_linenumber" name="60" href="#60">60</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> SHIFT_2 = 16;
<a class="jxr_linenumber" name="61" href="#61">61</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> SHIFT_4 = 32;
<a class="jxr_linenumber" name="62" href="#62">62</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> SHIFT_6 = 48;
<a class="jxr_linenumber" name="63" href="#63">63</a> <strong class="jxr_keyword">private</strong> <strong class="jxr_keyword">static</strong> <strong class="jxr_keyword">final</strong> <strong class="jxr_keyword">int</strong> HUNDRED_NANOS_PER_MILLI = 10000;
<a class="jxr_linenumber" name="64" href="#64">64</a>
<a class="jxr_linenumber" name="65" href="#65">65</a> <strong class="jxr_keyword">static</strong> {
<a class="jxr_linenumber" name="66" href="#66">66</a> byte[] mac = <strong class="jxr_keyword">null</strong>;
<a class="jxr_linenumber" name="67" href="#67">67</a> <strong class="jxr_keyword">try</strong> {
<a class="jxr_linenumber" name="68" href="#68">68</a> InetAddress address = InetAddress.getLocalHost();
<a class="jxr_linenumber" name="69" href="#69">69</a> <strong class="jxr_keyword">try</strong> {
<a class="jxr_linenumber" name="70" href="#70">70</a> NetworkInterface ni = NetworkInterface.getByInetAddress(address);
<a class="jxr_linenumber" name="71" href="#71">71</a> <strong class="jxr_keyword">if</strong> (ni != <strong class="jxr_keyword">null</strong> &amp;&amp; !ni.isLoopback() &amp;&amp; ni.isUp()) {
<a class="jxr_linenumber" name="72" href="#72">72</a> Method method = ni.getClass().getMethod(<span class="jxr_string">"getHardwareAddress"</span>);
<a class="jxr_linenumber" name="73" href="#73">73</a> <strong class="jxr_keyword">if</strong> (method != <strong class="jxr_keyword">null</strong>) {
<a class="jxr_linenumber" name="74" href="#74">74</a> mac = (byte[]) method.invoke(ni);
<a class="jxr_linenumber" name="75" href="#75">75</a> }
<a class="jxr_linenumber" name="76" href="#76">76</a> }
<a class="jxr_linenumber" name="77" href="#77">77</a>
<a class="jxr_linenumber" name="78" href="#78">78</a> <strong class="jxr_keyword">if</strong> (mac == <strong class="jxr_keyword">null</strong>) {
<a class="jxr_linenumber" name="79" href="#79">79</a> Enumeration&lt;NetworkInterface&gt; enumeration = NetworkInterface.getNetworkInterfaces();
<a class="jxr_linenumber" name="80" href="#80">80</a> <strong class="jxr_keyword">while</strong> (enumeration.hasMoreElements() &amp;&amp; mac == <strong class="jxr_keyword">null</strong>) {
<a class="jxr_linenumber" name="81" href="#81">81</a> ni = enumeration.nextElement();
<a class="jxr_linenumber" name="82" href="#82">82</a> <strong class="jxr_keyword">if</strong> (ni != <strong class="jxr_keyword">null</strong> &amp;&amp; ni.isUp() &amp;&amp; !ni.isLoopback()) {
<a class="jxr_linenumber" name="83" href="#83">83</a> Method method = ni.getClass().getMethod(<span class="jxr_string">"getHardwareAddress"</span>);
<a class="jxr_linenumber" name="84" href="#84">84</a> <strong class="jxr_keyword">if</strong> (method != <strong class="jxr_keyword">null</strong>) {
<a class="jxr_linenumber" name="85" href="#85">85</a> mac = (byte[]) method.invoke(ni);
<a class="jxr_linenumber" name="86" href="#86">86</a> }
<a class="jxr_linenumber" name="87" href="#87">87</a> }
<a class="jxr_linenumber" name="88" href="#88">88</a> }
<a class="jxr_linenumber" name="89" href="#89">89</a> }
<a class="jxr_linenumber" name="90" href="#90">90</a> } <strong class="jxr_keyword">catch</strong> (Exception ex) {
<a class="jxr_linenumber" name="91" href="#91">91</a> ex.printStackTrace();
<a class="jxr_linenumber" name="92" href="#92">92</a> <em class="jxr_comment">// Ignore exception</em>
<a class="jxr_linenumber" name="93" href="#93">93</a> }
<a class="jxr_linenumber" name="94" href="#94">94</a> <strong class="jxr_keyword">if</strong> (mac == <strong class="jxr_keyword">null</strong> || mac.length == 0) {
<a class="jxr_linenumber" name="95" href="#95">95</a> mac = address.getAddress();
<a class="jxr_linenumber" name="96" href="#96">96</a> }
<a class="jxr_linenumber" name="97" href="#97">97</a> } <strong class="jxr_keyword">catch</strong> (UnknownHostException e) {
<a class="jxr_linenumber" name="98" href="#98">98</a> <em class="jxr_comment">// Ignore exception</em>
<a class="jxr_linenumber" name="99" href="#99">99</a> }
<a class="jxr_linenumber" name="100" href="#100">100</a> Random randomGenerator = <strong class="jxr_keyword">new</strong> SecureRandom();
<a class="jxr_linenumber" name="101" href="#101">101</a> <strong class="jxr_keyword">if</strong> (mac == <strong class="jxr_keyword">null</strong> || mac.length == 0) {
<a class="jxr_linenumber" name="102" href="#102">102</a> mac = <strong class="jxr_keyword">new</strong> byte[6];
<a class="jxr_linenumber" name="103" href="#103">103</a> randomGenerator.nextBytes(mac);
<a class="jxr_linenumber" name="104" href="#104">104</a> }
<a class="jxr_linenumber" name="105" href="#105">105</a> <strong class="jxr_keyword">int</strong> length = mac.length &gt;= 6 ? 6 : mac.length;
<a class="jxr_linenumber" name="106" href="#106">106</a> <strong class="jxr_keyword">int</strong> index = mac.length &gt;= 6 ? mac.length - 6 : 0;
<a class="jxr_linenumber" name="107" href="#107">107</a> byte[] node = <strong class="jxr_keyword">new</strong> byte[NODE_SIZE];
<a class="jxr_linenumber" name="108" href="#108">108</a> node[0] = VARIANT;
<a class="jxr_linenumber" name="109" href="#109">109</a> node[1] = 0;
<a class="jxr_linenumber" name="110" href="#110">110</a> <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">int</strong> i = 2; i &lt; NODE_SIZE; ++i) {
<a class="jxr_linenumber" name="111" href="#111">111</a> node[i] = 0;
<a class="jxr_linenumber" name="112" href="#112">112</a> }
<a class="jxr_linenumber" name="113" href="#113">113</a> System.arraycopy(mac, index, node, index + 2, length);
<a class="jxr_linenumber" name="114" href="#114">114</a> ByteBuffer buf = ByteBuffer.wrap(node);
<a class="jxr_linenumber" name="115" href="#115">115</a> <strong class="jxr_keyword">long</strong> rand = uuidSequence;
<a class="jxr_linenumber" name="116" href="#116">116</a> Runtime runtime = Runtime.getRuntime();
<a class="jxr_linenumber" name="117" href="#117">117</a> <strong class="jxr_keyword">synchronized</strong> (runtime) {
<a class="jxr_linenumber" name="118" href="#118">118</a> String assigned = System.getProperty(ASSIGNED_SEQUENCES);
<a class="jxr_linenumber" name="119" href="#119">119</a> <strong class="jxr_keyword">long</strong>[] sequences;
<a class="jxr_linenumber" name="120" href="#120">120</a> <strong class="jxr_keyword">if</strong> (assigned == <strong class="jxr_keyword">null</strong>) {
<a class="jxr_linenumber" name="121" href="#121">121</a> sequences = <strong class="jxr_keyword">new</strong> <strong class="jxr_keyword">long</strong>[0];
<a class="jxr_linenumber" name="122" href="#122">122</a> } <strong class="jxr_keyword">else</strong> {
<a class="jxr_linenumber" name="123" href="#123">123</a> String[] array = assigned.split(<span class="jxr_string">","</span>);
<a class="jxr_linenumber" name="124" href="#124">124</a> sequences = <strong class="jxr_keyword">new</strong> <strong class="jxr_keyword">long</strong>[array.length];
<a class="jxr_linenumber" name="125" href="#125">125</a> <strong class="jxr_keyword">int</strong> i = 0;
<a class="jxr_linenumber" name="126" href="#126">126</a> <strong class="jxr_keyword">for</strong> (String value : array) {
<a class="jxr_linenumber" name="127" href="#127">127</a> sequences[i] = Long.parseLong(value);
<a class="jxr_linenumber" name="128" href="#128">128</a> ++i;
<a class="jxr_linenumber" name="129" href="#129">129</a> }
<a class="jxr_linenumber" name="130" href="#130">130</a> }
<a class="jxr_linenumber" name="131" href="#131">131</a> <strong class="jxr_keyword">if</strong> (rand == 0) {
<a class="jxr_linenumber" name="132" href="#132">132</a> rand = randomGenerator.nextLong();
<a class="jxr_linenumber" name="133" href="#133">133</a> }
<a class="jxr_linenumber" name="134" href="#134">134</a> rand &amp;= SEQUENCE_MASK;
<a class="jxr_linenumber" name="135" href="#135">135</a> <strong class="jxr_keyword">boolean</strong> duplicate;
<a class="jxr_linenumber" name="136" href="#136">136</a> <strong class="jxr_keyword">do</strong> {
<a class="jxr_linenumber" name="137" href="#137">137</a> duplicate = false;
<a class="jxr_linenumber" name="138" href="#138">138</a> <strong class="jxr_keyword">for</strong> (<strong class="jxr_keyword">long</strong> sequence : sequences) {
<a class="jxr_linenumber" name="139" href="#139">139</a> <strong class="jxr_keyword">if</strong> (sequence == rand) {
<a class="jxr_linenumber" name="140" href="#140">140</a> duplicate = <strong class="jxr_keyword">true</strong>;
<a class="jxr_linenumber" name="141" href="#141">141</a> }
<a class="jxr_linenumber" name="142" href="#142">142</a> }
<a class="jxr_linenumber" name="143" href="#143">143</a> <strong class="jxr_keyword">if</strong> (duplicate) {
<a class="jxr_linenumber" name="144" href="#144">144</a> rand = (rand + 1) &amp; SEQUENCE_MASK;
<a class="jxr_linenumber" name="145" href="#145">145</a> }
<a class="jxr_linenumber" name="146" href="#146">146</a> } <strong class="jxr_keyword">while</strong> (duplicate);
<a class="jxr_linenumber" name="147" href="#147">147</a> assigned = assigned == <strong class="jxr_keyword">null</strong> ? Long.toString(rand) : assigned + <span class="jxr_string">","</span> + Long.toString(rand);
<a class="jxr_linenumber" name="148" href="#148">148</a> System.setProperty(ASSIGNED_SEQUENCES, assigned);
<a class="jxr_linenumber" name="149" href="#149">149</a> }
<a class="jxr_linenumber" name="150" href="#150">150</a>
<a class="jxr_linenumber" name="151" href="#151">151</a> least = buf.getLong() | rand &lt;&lt; SHIFT_6;
<a class="jxr_linenumber" name="152" href="#152">152</a> }
<a class="jxr_linenumber" name="153" href="#153">153</a>
<a class="jxr_linenumber" name="154" href="#154">154</a>
<a class="jxr_linenumber" name="155" href="#155">155</a> <em class="jxr_comment">/*<em class="jxr_comment"> This class cannot be instantiated */</em></em>
<a class="jxr_linenumber" name="156" href="#156">156</a> <strong class="jxr_keyword">private</strong> <a href="../../../../../../org/apache/logging/log4j/core/helpers/UUIDUtil.html">UUIDUtil</a>() {
<a class="jxr_linenumber" name="157" href="#157">157</a> }
<a class="jxr_linenumber" name="158" href="#158">158</a>
<a class="jxr_linenumber" name="159" href="#159">159</a> <em class="jxr_javadoccomment">/**</em>
<a class="jxr_linenumber" name="160" href="#160">160</a> <em class="jxr_javadoccomment"> * Generates Type 1 UUID. The time contains the number of 100NS intervals that have occurred</em>
<a class="jxr_linenumber" name="161" href="#161">161</a> <em class="jxr_javadoccomment"> * since 00:00:00.00 UTC, 10 October 1582. Each UUID on a particular machine is unique to the 100NS interval</em>
<a class="jxr_linenumber" name="162" href="#162">162</a> <em class="jxr_javadoccomment"> * until they rollover around 3400 A.D.</em>
<a class="jxr_linenumber" name="163" href="#163">163</a> <em class="jxr_javadoccomment"> * &lt;ol&gt;</em>
<a class="jxr_linenumber" name="164" href="#164">164</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digits 1-12 are the lower 48 bits of the number of 100 ns increments since the start of the UUID</em>
<a class="jxr_linenumber" name="165" href="#165">165</a> <em class="jxr_javadoccomment"> * epoch.&lt;/li&gt;</em>
<a class="jxr_linenumber" name="166" href="#166">166</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digit 13 is the version (with a value of 1).&lt;/li&gt;</em>
<a class="jxr_linenumber" name="167" href="#167">167</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digits 14-16 are a sequence number that is incremented each time a UUID is generated.&lt;/li&gt;</em>
<a class="jxr_linenumber" name="168" href="#168">168</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digit 17 is the variant (with a value of binary 10) and 10 bits of the sequence number&lt;/li&gt;</em>
<a class="jxr_linenumber" name="169" href="#169">169</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digit 18 is final 16 bits of the sequence number.&lt;/li&gt;</em>
<a class="jxr_linenumber" name="170" href="#170">170</a> <em class="jxr_javadoccomment"> * &lt;li&gt;Digits 19-32 represent the system the application is running on.</em>
<a class="jxr_linenumber" name="171" href="#171">171</a> <em class="jxr_javadoccomment"> * &lt;/ol&gt;</em>
<a class="jxr_linenumber" name="172" href="#172">172</a> <em class="jxr_javadoccomment"> *</em>
<a class="jxr_linenumber" name="173" href="#173">173</a> <em class="jxr_javadoccomment"> * @return universally unique identifiers (UUID)</em>
<a class="jxr_linenumber" name="174" href="#174">174</a> <em class="jxr_javadoccomment"> */</em>
<a class="jxr_linenumber" name="175" href="#175">175</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">static</strong> UUID getTimeBasedUUID() {
<a class="jxr_linenumber" name="176" href="#176">176</a>
<a class="jxr_linenumber" name="177" href="#177">177</a> <strong class="jxr_keyword">long</strong> time = ((System.currentTimeMillis() * HUNDRED_NANOS_PER_MILLI) + NUM_100NS_INTERVALS_SINCE_UUID_EPOCH) +
<a class="jxr_linenumber" name="178" href="#178">178</a> (count.incrementAndGet() % HUNDRED_NANOS_PER_MILLI);
<a class="jxr_linenumber" name="179" href="#179">179</a> <strong class="jxr_keyword">long</strong> timeLow = (time &amp; LOW_MASK) &lt;&lt; SHIFT_4;
<a class="jxr_linenumber" name="180" href="#180">180</a> <strong class="jxr_keyword">long</strong> timeMid = (time &amp; MID_MASK) &gt;&gt; SHIFT_2;
<a class="jxr_linenumber" name="181" href="#181">181</a> <strong class="jxr_keyword">long</strong> timeHi = (time &amp; HIGH_MASK) &gt;&gt; SHIFT_6;
<a class="jxr_linenumber" name="182" href="#182">182</a> <strong class="jxr_keyword">long</strong> most = timeLow | timeMid | TYPE1 | timeHi;
<a class="jxr_linenumber" name="183" href="#183">183</a> <strong class="jxr_keyword">return</strong> <strong class="jxr_keyword">new</strong> UUID(most, least);
<a class="jxr_linenumber" name="184" href="#184">184</a> }
<a class="jxr_linenumber" name="185" href="#185">185</a> }
<a class="jxr_linenumber" name="186" href="#186">186</a>
</pre>
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