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| <a class="jxr_linenumber" name="L1" href="#L1">1</a> <em class="jxr_comment">/*</em> |
| <a class="jxr_linenumber" name="L2" href="#L2">2</a> <em class="jxr_comment"> * Licensed to the Apache Software Foundation (ASF) under one or more</em> |
| <a class="jxr_linenumber" name="L3" href="#L3">3</a> <em class="jxr_comment"> * contributor license agreements. See the NOTICE file distributed with</em> |
| <a class="jxr_linenumber" name="L4" href="#L4">4</a> <em class="jxr_comment"> * this work for additional information regarding copyright ownership.</em> |
| <a class="jxr_linenumber" name="L5" href="#L5">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="L6" href="#L6">6</a> <em class="jxr_comment"> * (the "License"); you may not use this file except in compliance with</em> |
| <a class="jxr_linenumber" name="L7" href="#L7">7</a> <em class="jxr_comment"> * the License. You may obtain a copy of the License at</em> |
| <a class="jxr_linenumber" name="L8" href="#L8">8</a> <em class="jxr_comment"> *</em> |
| <a class="jxr_linenumber" name="L9" href="#L9">9</a> <em class="jxr_comment"> * <a href="http://www.apache.org/licenses/LICENSE-2." target="alexandria_uri">http://www.apache.org/licenses/LICENSE-2.</a>0</em> |
| <a class="jxr_linenumber" name="L10" href="#L10">10</a> <em class="jxr_comment"> *</em> |
| <a class="jxr_linenumber" name="L11" href="#L11">11</a> <em class="jxr_comment"> * Unless required by applicable law or agreed to in writing, software</em> |
| <a class="jxr_linenumber" name="L12" href="#L12">12</a> <em class="jxr_comment"> * distributed under the License is distributed on an "AS IS" BASIS,</em> |
| <a class="jxr_linenumber" name="L13" href="#L13">13</a> <em class="jxr_comment"> * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</em> |
| <a class="jxr_linenumber" name="L14" href="#L14">14</a> <em class="jxr_comment"> * See the license for the specific language governing permissions and</em> |
| <a class="jxr_linenumber" name="L15" href="#L15">15</a> <em class="jxr_comment"> * limitations under the license.</em> |
| <a class="jxr_linenumber" name="L16" href="#L16">16</a> <em class="jxr_comment"> */</em> |
| <a class="jxr_linenumber" name="L17" href="#L17">17</a> <strong class="jxr_keyword">package</strong> org.apache.logging.log4j.core; |
| <a class="jxr_linenumber" name="L18" href="#L18">18</a> |
| <a class="jxr_linenumber" name="L19" href="#L19">19</a> <strong class="jxr_keyword">import</strong> java.util.List; |
| <a class="jxr_linenumber" name="L20" href="#L20">20</a> |
| <a class="jxr_linenumber" name="L21" href="#L21">21</a> <strong class="jxr_keyword">import</strong> org.apache.logging.log4j.core.config.Property; |
| <a class="jxr_linenumber" name="L22" href="#L22">22</a> <strong class="jxr_keyword">import</strong> org.apache.logging.log4j.core.impl.ContextDataInjectorFactory; |
| <a class="jxr_linenumber" name="L23" href="#L23">23</a> <strong class="jxr_keyword">import</strong> org.apache.logging.log4j.core.impl.ThreadContextDataInjector; |
| <a class="jxr_linenumber" name="L24" href="#L24">24</a> <strong class="jxr_keyword">import</strong> org.apache.logging.log4j.util.ReadOnlyStringMap; |
| <a class="jxr_linenumber" name="L25" href="#L25">25</a> <strong class="jxr_keyword">import</strong> org.apache.logging.log4j.util.StringMap; |
| <a class="jxr_linenumber" name="L26" href="#L26">26</a> |
| <a class="jxr_linenumber" name="L27" href="#L27">27</a> <em class="jxr_javadoccomment">/**</em> |
| <a class="jxr_linenumber" name="L28" href="#L28">28</a> <em class="jxr_javadoccomment"> * Responsible for initializing the context data of LogEvents. Context data is data that is set by the application to be</em> |
| <a class="jxr_linenumber" name="L29" href="#L29">29</a> <em class="jxr_javadoccomment"> * included in all subsequent log events.</em> |
| <a class="jxr_linenumber" name="L30" href="#L30">30</a> <em class="jxr_javadoccomment"> * <p></em> |
| <a class="jxr_linenumber" name="L31" href="#L31">31</a> <em class="jxr_javadoccomment"> * The source of the context data is implementation-specific. The default source for context data is the ThreadContext.</em> |
| <a class="jxr_linenumber" name="L32" href="#L32">32</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L33" href="#L33">33</a> <em class="jxr_javadoccomment"> * In some asynchronous models, work may be delegated to several threads, while conceptually this work shares the same</em> |
| <a class="jxr_linenumber" name="L34" href="#L34">34</a> <em class="jxr_javadoccomment"> * context. In such models, storing context data in {@code ThreadLocal} variables is not convenient or desirable.</em> |
| <a class="jxr_linenumber" name="L35" href="#L35">35</a> <em class="jxr_javadoccomment"> * Users can configure the {@code ContextDataInjectorFactory} to provide custom {@code ContextDataInjector} objects,</em> |
| <a class="jxr_linenumber" name="L36" href="#L36">36</a> <em class="jxr_javadoccomment"> * in order to initialize log events with context data from any arbitrary context.</em> |
| <a class="jxr_linenumber" name="L37" href="#L37">37</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L38" href="#L38">38</a> <em class="jxr_javadoccomment"> * When providing a custom {@code ContextDataInjector}, be aware that the {@code ContextDataInjectorFactory} may be</em> |
| <a class="jxr_linenumber" name="L39" href="#L39">39</a> <em class="jxr_javadoccomment"> * invoked multiple times and the various components in Log4j that need access to context data may each have their own</em> |
| <a class="jxr_linenumber" name="L40" href="#L40">40</a> <em class="jxr_javadoccomment"> * instance of {@code ContextDataInjector}.</em> |
| <a class="jxr_linenumber" name="L41" href="#L41">41</a> <em class="jxr_javadoccomment"> * This includes the object(s) that populate log events, but also various lookups and filters that look at</em> |
| <a class="jxr_linenumber" name="L42" href="#L42">42</a> <em class="jxr_javadoccomment"> * context data to determine whether an event should be logged.</em> |
| <a class="jxr_linenumber" name="L43" href="#L43">43</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L44" href="#L44">44</a> <em class="jxr_javadoccomment"> * Implementors should take particular note of how the different methods in the interface have different thread-safety</em> |
| <a class="jxr_linenumber" name="L45" href="#L45">45</a> <em class="jxr_javadoccomment"> * guarantees to enable optimal performance.</em> |
| <a class="jxr_linenumber" name="L46" href="#L46">46</a> <em class="jxr_javadoccomment"> * </p></em> |
| <a class="jxr_linenumber" name="L47" href="#L47">47</a> <em class="jxr_javadoccomment"> *</em> |
| <a class="jxr_linenumber" name="L48" href="#L48">48</a> <em class="jxr_javadoccomment"> * @see StringMap</em> |
| <a class="jxr_linenumber" name="L49" href="#L49">49</a> <em class="jxr_javadoccomment"> * @see ReadOnlyStringMap</em> |
| <a class="jxr_linenumber" name="L50" href="#L50">50</a> <em class="jxr_javadoccomment"> * @see ContextDataInjectorFactory</em> |
| <a class="jxr_linenumber" name="L51" href="#L51">51</a> <em class="jxr_javadoccomment"> * @see org.apache.logging.log4j.ThreadContext</em> |
| <a class="jxr_linenumber" name="L52" href="#L52">52</a> <em class="jxr_javadoccomment"> * @see ThreadContextDataInjector</em> |
| <a class="jxr_linenumber" name="L53" href="#L53">53</a> <em class="jxr_javadoccomment"> * @since 2.7</em> |
| <a class="jxr_linenumber" name="L54" href="#L54">54</a> <em class="jxr_javadoccomment"> */</em> |
| <a class="jxr_linenumber" name="L55" href="#L55">55</a> <strong class="jxr_keyword">public</strong> <strong class="jxr_keyword">interface</strong> <a href="../../../../../org/apache/logging/log4j/core/ContextDataInjector.html">ContextDataInjector</a> { |
| <a class="jxr_linenumber" name="L56" href="#L56">56</a> <em class="jxr_javadoccomment">/**</em> |
| <a class="jxr_linenumber" name="L57" href="#L57">57</a> <em class="jxr_javadoccomment"> * Returns a {@code StringMap} object initialized with the specified properties and the appropriate</em> |
| <a class="jxr_linenumber" name="L58" href="#L58">58</a> <em class="jxr_javadoccomment"> * context data. The returned value may be the specified parameter or a different object.</em> |
| <a class="jxr_linenumber" name="L59" href="#L59">59</a> <em class="jxr_javadoccomment"> * <p></em> |
| <a class="jxr_linenumber" name="L60" href="#L60">60</a> <em class="jxr_javadoccomment"> * This method will be called for each log event to initialize its context data and implementors should take</em> |
| <a class="jxr_linenumber" name="L61" href="#L61">61</a> <em class="jxr_javadoccomment"> * care to make this method as performant as possible while preserving at least the following thread-safety</em> |
| <a class="jxr_linenumber" name="L62" href="#L62">62</a> <em class="jxr_javadoccomment"> * guarantee.</em> |
| <a class="jxr_linenumber" name="L63" href="#L63">63</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L64" href="#L64">64</a> <em class="jxr_javadoccomment"> * Thread-safety note: The returned object can safely be passed off to another thread: future changes in the</em> |
| <a class="jxr_linenumber" name="L65" href="#L65">65</a> <em class="jxr_javadoccomment"> * underlying context data will not be reflected in the returned object.</em> |
| <a class="jxr_linenumber" name="L66" href="#L66">66</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L67" href="#L67">67</a> <em class="jxr_javadoccomment"> * Example implementation:</em> |
| <a class="jxr_linenumber" name="L68" href="#L68">68</a> <em class="jxr_javadoccomment"> * </p></em> |
| <a class="jxr_linenumber" name="L69" href="#L69">69</a> <em class="jxr_javadoccomment"> * <pre></em> |
| <a class="jxr_linenumber" name="L70" href="#L70">70</a> <em class="jxr_javadoccomment"> * public StringMap injectContextData(List<Property> properties, StringMap reusable) {</em> |
| <a class="jxr_linenumber" name="L71" href="#L71">71</a> <em class="jxr_javadoccomment"> * if (properties == null || properties.isEmpty()) {</em> |
| <a class="jxr_linenumber" name="L72" href="#L72">72</a> <em class="jxr_javadoccomment"> * // assume context data is stored in a copy-on-write data structure that is safe to pass to another thread</em> |
| <a class="jxr_linenumber" name="L73" href="#L73">73</a> <em class="jxr_javadoccomment"> * return (StringMap) rawContextData();</em> |
| <a class="jxr_linenumber" name="L74" href="#L74">74</a> <em class="jxr_javadoccomment"> * }</em> |
| <a class="jxr_linenumber" name="L75" href="#L75">75</a> <em class="jxr_javadoccomment"> * // first copy configuration properties into the result</em> |
| <a class="jxr_linenumber" name="L76" href="#L76">76</a> <em class="jxr_javadoccomment"> * ThreadContextDataInjector.copyProperties(properties, reusable);</em> |
| <a class="jxr_linenumber" name="L77" href="#L77">77</a> <em class="jxr_javadoccomment"> *</em> |
| <a class="jxr_linenumber" name="L78" href="#L78">78</a> <em class="jxr_javadoccomment"> * // then copy context data key-value pairs (may overwrite configuration properties)</em> |
| <a class="jxr_linenumber" name="L79" href="#L79">79</a> <em class="jxr_javadoccomment"> * reusable.putAll(rawContextData());</em> |
| <a class="jxr_linenumber" name="L80" href="#L80">80</a> <em class="jxr_javadoccomment"> * return reusable;</em> |
| <a class="jxr_linenumber" name="L81" href="#L81">81</a> <em class="jxr_javadoccomment"> * }</em> |
| <a class="jxr_linenumber" name="L82" href="#L82">82</a> <em class="jxr_javadoccomment"> * </pre></em> |
| <a class="jxr_linenumber" name="L83" href="#L83">83</a> <em class="jxr_javadoccomment"> *</em> |
| <a class="jxr_linenumber" name="L84" href="#L84">84</a> <em class="jxr_javadoccomment"> * @param properties Properties from the log4j configuration to be added to the resulting ReadOnlyStringMap. May be</em> |
| <a class="jxr_linenumber" name="L85" href="#L85">85</a> <em class="jxr_javadoccomment"> * {@code null} or empty</em> |
| <a class="jxr_linenumber" name="L86" href="#L86">86</a> <em class="jxr_javadoccomment"> * @param reusable a {@code StringMap} instance that may be reused to avoid creating temporary objects</em> |
| <a class="jxr_linenumber" name="L87" href="#L87">87</a> <em class="jxr_javadoccomment"> * @return a {@code StringMap} instance initialized with the specified properties and the appropriate</em> |
| <a class="jxr_linenumber" name="L88" href="#L88">88</a> <em class="jxr_javadoccomment"> * context data. The returned value may be the specified parameter or a different object.</em> |
| <a class="jxr_linenumber" name="L89" href="#L89">89</a> <em class="jxr_javadoccomment"> * @see ThreadContextDataInjector#copyProperties(List, StringMap)</em> |
| <a class="jxr_linenumber" name="L90" href="#L90">90</a> <em class="jxr_javadoccomment"> */</em> |
| <a class="jxr_linenumber" name="L91" href="#L91">91</a> StringMap injectContextData(<strong class="jxr_keyword">final</strong> List<Property> properties, <strong class="jxr_keyword">final</strong> StringMap reusable); |
| <a class="jxr_linenumber" name="L92" href="#L92">92</a> |
| <a class="jxr_linenumber" name="L93" href="#L93">93</a> <em class="jxr_javadoccomment">/**</em> |
| <a class="jxr_linenumber" name="L94" href="#L94">94</a> <em class="jxr_javadoccomment"> * Returns a {@code ReadOnlyStringMap} object reflecting the current state of the context. Configuration properties</em> |
| <a class="jxr_linenumber" name="L95" href="#L95">95</a> <em class="jxr_javadoccomment"> * are not included in the result.</em> |
| <a class="jxr_linenumber" name="L96" href="#L96">96</a> <em class="jxr_javadoccomment"> * <p></em> |
| <a class="jxr_linenumber" name="L97" href="#L97">97</a> <em class="jxr_javadoccomment"> * This method may be called multiple times for each log event by Filters and Lookups and implementors should take</em> |
| <a class="jxr_linenumber" name="L98" href="#L98">98</a> <em class="jxr_javadoccomment"> * care to make this method as performant as possible while preserving at least the following thread-safety</em> |
| <a class="jxr_linenumber" name="L99" href="#L99">99</a> <em class="jxr_javadoccomment"> * guarantee.</em> |
| <a class="jxr_linenumber" name="L100" href="#L100">100</a> <em class="jxr_javadoccomment"> * </p><p></em> |
| <a class="jxr_linenumber" name="L101" href="#L101">101</a> <em class="jxr_javadoccomment"> * Thread-safety note: The returned object can only be safely used <em>in the current thread</em>. Changes in the</em> |
| <a class="jxr_linenumber" name="L102" href="#L102">102</a> <em class="jxr_javadoccomment"> * underlying context may or may not be reflected in the returned object, depending on the context data source and</em> |
| <a class="jxr_linenumber" name="L103" href="#L103">103</a> <em class="jxr_javadoccomment"> * the implementation of this method. It is not safe to pass the returned object to another thread.</em> |
| <a class="jxr_linenumber" name="L104" href="#L104">104</a> <em class="jxr_javadoccomment"> * </p></em> |
| <a class="jxr_linenumber" name="L105" href="#L105">105</a> <em class="jxr_javadoccomment"> * @return a {@code ReadOnlyStringMap} object reflecting the current state of the context, may not return {@code null}</em> |
| <a class="jxr_linenumber" name="L106" href="#L106">106</a> <em class="jxr_javadoccomment"> */</em> |
| <a class="jxr_linenumber" name="L107" href="#L107">107</a> ReadOnlyStringMap rawContextData(); |
| <a class="jxr_linenumber" name="L108" href="#L108">108</a> } |
| </pre> |
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