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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Licensed to the Apache Software Foundation (ASF) under one or more<a name="line.2"></a>
<FONT color="green">003</FONT>     * contributor license agreements. See the NOTICE file distributed with<a name="line.3"></a>
<FONT color="green">004</FONT>     * this work for additional information regarding copyright ownership.<a name="line.4"></a>
<FONT color="green">005</FONT>     * The ASF licenses this file to You under the Apache license, Version 2.0<a name="line.5"></a>
<FONT color="green">006</FONT>     * (the "License"); you may not use this file except in compliance with<a name="line.6"></a>
<FONT color="green">007</FONT>     * the License. You may obtain a copy of the License at<a name="line.7"></a>
<FONT color="green">008</FONT>     *<a name="line.8"></a>
<FONT color="green">009</FONT>     *      http://www.apache.org/licenses/LICENSE-2.0<a name="line.9"></a>
<FONT color="green">010</FONT>     *<a name="line.10"></a>
<FONT color="green">011</FONT>     * Unless required by applicable law or agreed to in writing, software<a name="line.11"></a>
<FONT color="green">012</FONT>     * distributed under the License is distributed on an "AS IS" BASIS,<a name="line.12"></a>
<FONT color="green">013</FONT>     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.<a name="line.13"></a>
<FONT color="green">014</FONT>     * See the license for the specific language governing permissions and<a name="line.14"></a>
<FONT color="green">015</FONT>     * limitations under the license.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    package org.apache.logging.log4j.core.selector;<a name="line.17"></a>
<FONT color="green">018</FONT>    <a name="line.18"></a>
<FONT color="green">019</FONT>    import org.apache.logging.log4j.core.LoggerContext;<a name="line.19"></a>
<FONT color="green">020</FONT>    import org.apache.logging.log4j.core.helpers.Loader;<a name="line.20"></a>
<FONT color="green">021</FONT>    import org.apache.logging.log4j.core.javaee.ContextAnchor;<a name="line.21"></a>
<FONT color="green">022</FONT>    import org.apache.logging.log4j.status.StatusLogger;<a name="line.22"></a>
<FONT color="green">023</FONT>    <a name="line.23"></a>
<FONT color="green">024</FONT>    import java.lang.ref.WeakReference;<a name="line.24"></a>
<FONT color="green">025</FONT>    import java.lang.reflect.Method;<a name="line.25"></a>
<FONT color="green">026</FONT>    import java.lang.reflect.Modifier;<a name="line.26"></a>
<FONT color="green">027</FONT>    import java.util.ArrayList;<a name="line.27"></a>
<FONT color="green">028</FONT>    import java.util.Collection;<a name="line.28"></a>
<FONT color="green">029</FONT>    import java.util.Collections;<a name="line.29"></a>
<FONT color="green">030</FONT>    import java.util.List;<a name="line.30"></a>
<FONT color="green">031</FONT>    import java.util.Map;<a name="line.31"></a>
<FONT color="green">032</FONT>    import java.util.concurrent.ConcurrentHashMap;<a name="line.32"></a>
<FONT color="green">033</FONT>    import java.util.concurrent.ConcurrentMap;<a name="line.33"></a>
<FONT color="green">034</FONT>    import java.util.concurrent.atomic.AtomicReference;<a name="line.34"></a>
<FONT color="green">035</FONT>    <a name="line.35"></a>
<FONT color="green">036</FONT>    /**<a name="line.36"></a>
<FONT color="green">037</FONT>     * This ContextSelector chooses a LoggerContext based upon the ClassLoader of the caller. This allows Loggers<a name="line.37"></a>
<FONT color="green">038</FONT>     * assigned to static variables to be released along with the classes that own then. Other ContextSelectors<a name="line.38"></a>
<FONT color="green">039</FONT>     * will generally cause Loggers associated with classes loaded from different ClassLoaders to be co-mingled.<a name="line.39"></a>
<FONT color="green">040</FONT>     * This is a problem if, for example, a web application is undeployed as some of the Loggers being released may be<a name="line.40"></a>
<FONT color="green">041</FONT>     * associated with a Class in a parent ClassLoader, which will generally have negative consequences.<a name="line.41"></a>
<FONT color="green">042</FONT>     *<a name="line.42"></a>
<FONT color="green">043</FONT>     * The main downside to this ContextSelector is that Configuration is more challenging.<a name="line.43"></a>
<FONT color="green">044</FONT>     *<a name="line.44"></a>
<FONT color="green">045</FONT>     * This ContextSelector should not be used with a Servlet Filter such as the JNDIContextFilter.<a name="line.45"></a>
<FONT color="green">046</FONT>     */<a name="line.46"></a>
<FONT color="green">047</FONT>    public class ClassLoaderContextSelector implements ContextSelector {<a name="line.47"></a>
<FONT color="green">048</FONT>    <a name="line.48"></a>
<FONT color="green">049</FONT>        private static AtomicReference&lt;LoggerContext&gt; context = new AtomicReference&lt;LoggerContext&gt;();<a name="line.49"></a>
<FONT color="green">050</FONT>    <a name="line.50"></a>
<FONT color="green">051</FONT>        private static PrivateSecurityManager securityManager;<a name="line.51"></a>
<FONT color="green">052</FONT>    <a name="line.52"></a>
<FONT color="green">053</FONT>        private static Method getCallerClass;<a name="line.53"></a>
<FONT color="green">054</FONT>    <a name="line.54"></a>
<FONT color="green">055</FONT>        private static StatusLogger logger = StatusLogger.getLogger();<a name="line.55"></a>
<FONT color="green">056</FONT>    <a name="line.56"></a>
<FONT color="green">057</FONT>        private static ConcurrentMap&lt;String, AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt;&gt; contextMap =<a name="line.57"></a>
<FONT color="green">058</FONT>            new ConcurrentHashMap&lt;String, AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt;&gt;();<a name="line.58"></a>
<FONT color="green">059</FONT>    <a name="line.59"></a>
<FONT color="green">060</FONT>    <a name="line.60"></a>
<FONT color="green">061</FONT>        static {<a name="line.61"></a>
<FONT color="green">062</FONT>            setupCallerCheck();<a name="line.62"></a>
<FONT color="green">063</FONT>        }<a name="line.63"></a>
<FONT color="green">064</FONT>    <a name="line.64"></a>
<FONT color="green">065</FONT>        public LoggerContext getContext(String fqcn, boolean currentContext) {<a name="line.65"></a>
<FONT color="green">066</FONT>    <a name="line.66"></a>
<FONT color="green">067</FONT>            if (currentContext) {<a name="line.67"></a>
<FONT color="green">068</FONT>                LoggerContext ctx = ContextAnchor.THREAD_CONTEXT.get();<a name="line.68"></a>
<FONT color="green">069</FONT>                if (ctx != null) {<a name="line.69"></a>
<FONT color="green">070</FONT>                    return ctx;<a name="line.70"></a>
<FONT color="green">071</FONT>                }<a name="line.71"></a>
<FONT color="green">072</FONT>                return getDefault();<a name="line.72"></a>
<FONT color="green">073</FONT>            } else {<a name="line.73"></a>
<FONT color="green">074</FONT>                if (getCallerClass != null) {<a name="line.74"></a>
<FONT color="green">075</FONT>                    try {<a name="line.75"></a>
<FONT color="green">076</FONT>                        Class clazz = Class.class;<a name="line.76"></a>
<FONT color="green">077</FONT>                        boolean next = false;<a name="line.77"></a>
<FONT color="green">078</FONT>                        for (int index = 2; clazz != null; ++index) {<a name="line.78"></a>
<FONT color="green">079</FONT>                            Object[] params = new Object[] {index};<a name="line.79"></a>
<FONT color="green">080</FONT>                            clazz = (Class) getCallerClass.invoke(null, params);<a name="line.80"></a>
<FONT color="green">081</FONT>                            if (clazz == null) {<a name="line.81"></a>
<FONT color="green">082</FONT>                                break;<a name="line.82"></a>
<FONT color="green">083</FONT>                            }<a name="line.83"></a>
<FONT color="green">084</FONT>                            if (clazz.getName().equals(fqcn)) {<a name="line.84"></a>
<FONT color="green">085</FONT>                                next = true;<a name="line.85"></a>
<FONT color="green">086</FONT>                                continue;<a name="line.86"></a>
<FONT color="green">087</FONT>                            }<a name="line.87"></a>
<FONT color="green">088</FONT>                            if (next) {<a name="line.88"></a>
<FONT color="green">089</FONT>                                break;<a name="line.89"></a>
<FONT color="green">090</FONT>                            }<a name="line.90"></a>
<FONT color="green">091</FONT>                        }<a name="line.91"></a>
<FONT color="green">092</FONT>                        if (clazz != null) {<a name="line.92"></a>
<FONT color="green">093</FONT>                            return locateContext(clazz.getClassLoader(), null);<a name="line.93"></a>
<FONT color="green">094</FONT>                        }<a name="line.94"></a>
<FONT color="green">095</FONT>                    } catch (Exception ex) {<a name="line.95"></a>
<FONT color="green">096</FONT>                        // logger.debug("Unable to determine caller class via Sun Reflection", ex);<a name="line.96"></a>
<FONT color="green">097</FONT>                    }<a name="line.97"></a>
<FONT color="green">098</FONT>                }<a name="line.98"></a>
<FONT color="green">099</FONT>    <a name="line.99"></a>
<FONT color="green">100</FONT>                if (securityManager != null) {<a name="line.100"></a>
<FONT color="green">101</FONT>                    Class clazz = securityManager.getCaller(fqcn);<a name="line.101"></a>
<FONT color="green">102</FONT>                    return locateContext(clazz.getClassLoader(), null);<a name="line.102"></a>
<FONT color="green">103</FONT>                }<a name="line.103"></a>
<FONT color="green">104</FONT>    <a name="line.104"></a>
<FONT color="green">105</FONT>                Throwable t = new Throwable();<a name="line.105"></a>
<FONT color="green">106</FONT>                boolean next = false;<a name="line.106"></a>
<FONT color="green">107</FONT>                String name = null;<a name="line.107"></a>
<FONT color="green">108</FONT>                for (StackTraceElement element : t.getStackTrace()) {<a name="line.108"></a>
<FONT color="green">109</FONT>                    if (element.getClassName().equals(fqcn)) {<a name="line.109"></a>
<FONT color="green">110</FONT>                        next = true;<a name="line.110"></a>
<FONT color="green">111</FONT>                        continue;<a name="line.111"></a>
<FONT color="green">112</FONT>                    }<a name="line.112"></a>
<FONT color="green">113</FONT>                    if (next) {<a name="line.113"></a>
<FONT color="green">114</FONT>                        name = element.getClassName();<a name="line.114"></a>
<FONT color="green">115</FONT>                        break;<a name="line.115"></a>
<FONT color="green">116</FONT>                    }<a name="line.116"></a>
<FONT color="green">117</FONT>                }<a name="line.117"></a>
<FONT color="green">118</FONT>                if (name != null) {<a name="line.118"></a>
<FONT color="green">119</FONT>                    try {<a name="line.119"></a>
<FONT color="green">120</FONT>                        return locateContext(Loader.loadClass(name).getClassLoader(), null);<a name="line.120"></a>
<FONT color="green">121</FONT>                    } catch (ClassNotFoundException ex) {<a name="line.121"></a>
<FONT color="green">122</FONT>                        //System.out.println("Could not load class " + name);<a name="line.122"></a>
<FONT color="green">123</FONT>                    }<a name="line.123"></a>
<FONT color="green">124</FONT>                }<a name="line.124"></a>
<FONT color="green">125</FONT>                LoggerContext lc = ContextAnchor.THREAD_CONTEXT.get();<a name="line.125"></a>
<FONT color="green">126</FONT>                if (lc != null) {<a name="line.126"></a>
<FONT color="green">127</FONT>                    return lc;<a name="line.127"></a>
<FONT color="green">128</FONT>                }<a name="line.128"></a>
<FONT color="green">129</FONT>                return getDefault();<a name="line.129"></a>
<FONT color="green">130</FONT>            }<a name="line.130"></a>
<FONT color="green">131</FONT>        }<a name="line.131"></a>
<FONT color="green">132</FONT>    <a name="line.132"></a>
<FONT color="green">133</FONT>        public void removeContext(LoggerContext context) {<a name="line.133"></a>
<FONT color="green">134</FONT>    <a name="line.134"></a>
<FONT color="green">135</FONT>            for (Map.Entry&lt;String, AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt;&gt; entry : contextMap.entrySet()) {<a name="line.135"></a>
<FONT color="green">136</FONT>                LoggerContext ctx = entry.getValue().get().get();<a name="line.136"></a>
<FONT color="green">137</FONT>                if (ctx == context) {<a name="line.137"></a>
<FONT color="green">138</FONT>                    contextMap.remove(entry.getKey());<a name="line.138"></a>
<FONT color="green">139</FONT>                }<a name="line.139"></a>
<FONT color="green">140</FONT>            }<a name="line.140"></a>
<FONT color="green">141</FONT>        }<a name="line.141"></a>
<FONT color="green">142</FONT>    <a name="line.142"></a>
<FONT color="green">143</FONT>        public List&lt;LoggerContext&gt; getLoggerContexts() {<a name="line.143"></a>
<FONT color="green">144</FONT>            List&lt;LoggerContext&gt; list = new ArrayList&lt;LoggerContext&gt;();<a name="line.144"></a>
<FONT color="green">145</FONT>            Collection&lt;AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt;&gt; coll = contextMap.values();<a name="line.145"></a>
<FONT color="green">146</FONT>            for (AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt; ref : coll) {<a name="line.146"></a>
<FONT color="green">147</FONT>                LoggerContext ctx = ref.get().get();<a name="line.147"></a>
<FONT color="green">148</FONT>                if (ctx != null) {<a name="line.148"></a>
<FONT color="green">149</FONT>                    list.add(ctx);<a name="line.149"></a>
<FONT color="green">150</FONT>                }<a name="line.150"></a>
<FONT color="green">151</FONT>            }<a name="line.151"></a>
<FONT color="green">152</FONT>            return Collections.unmodifiableList(list);<a name="line.152"></a>
<FONT color="green">153</FONT>        }<a name="line.153"></a>
<FONT color="green">154</FONT>    <a name="line.154"></a>
<FONT color="green">155</FONT>        private LoggerContext locateContext(ClassLoader loader, String configLocation) {<a name="line.155"></a>
<FONT color="green">156</FONT>            String name = loader.toString();<a name="line.156"></a>
<FONT color="green">157</FONT>            AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt; ref = contextMap.get(name);<a name="line.157"></a>
<FONT color="green">158</FONT>            if (ref == null) {<a name="line.158"></a>
<FONT color="green">159</FONT>                LoggerContext ctx = new LoggerContext(name, null, configLocation);<a name="line.159"></a>
<FONT color="green">160</FONT>                AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt; r =<a name="line.160"></a>
<FONT color="green">161</FONT>                    new AtomicReference&lt;WeakReference&lt;LoggerContext&gt;&gt;();<a name="line.161"></a>
<FONT color="green">162</FONT>                r.set(new WeakReference&lt;LoggerContext&gt;(ctx));<a name="line.162"></a>
<FONT color="green">163</FONT>                contextMap.putIfAbsent(loader.toString(), r);<a name="line.163"></a>
<FONT color="green">164</FONT>                ctx = contextMap.get(name).get().get();<a name="line.164"></a>
<FONT color="green">165</FONT>                return ctx;<a name="line.165"></a>
<FONT color="green">166</FONT>            } else {<a name="line.166"></a>
<FONT color="green">167</FONT>                WeakReference&lt;LoggerContext&gt; r = ref.get();<a name="line.167"></a>
<FONT color="green">168</FONT>                LoggerContext ctx = r.get();<a name="line.168"></a>
<FONT color="green">169</FONT>                if (ctx != null) {<a name="line.169"></a>
<FONT color="green">170</FONT>                    return ctx;<a name="line.170"></a>
<FONT color="green">171</FONT>                }<a name="line.171"></a>
<FONT color="green">172</FONT>                ctx = new LoggerContext(name, null, configLocation);<a name="line.172"></a>
<FONT color="green">173</FONT>                ref.compareAndSet(r, new WeakReference&lt;LoggerContext&gt;(ctx));<a name="line.173"></a>
<FONT color="green">174</FONT>                return ctx;<a name="line.174"></a>
<FONT color="green">175</FONT>            }<a name="line.175"></a>
<FONT color="green">176</FONT>        }<a name="line.176"></a>
<FONT color="green">177</FONT>    <a name="line.177"></a>
<FONT color="green">178</FONT>        private static void setupCallerCheck() {<a name="line.178"></a>
<FONT color="green">179</FONT>            try {<a name="line.179"></a>
<FONT color="green">180</FONT>                ClassLoader loader = Loader.getClassLoader();<a name="line.180"></a>
<FONT color="green">181</FONT>                Class clazz = loader.loadClass("sun.reflect.Reflection");<a name="line.181"></a>
<FONT color="green">182</FONT>                Method[] methods = clazz.getMethods();<a name="line.182"></a>
<FONT color="green">183</FONT>                for (Method method : methods) {<a name="line.183"></a>
<FONT color="green">184</FONT>                    int modifier = method.getModifiers();<a name="line.184"></a>
<FONT color="green">185</FONT>                    if (method.getName().equals("getCallerClass") &amp;&amp; Modifier.isStatic(modifier)) {<a name="line.185"></a>
<FONT color="green">186</FONT>                        getCallerClass = method;<a name="line.186"></a>
<FONT color="green">187</FONT>                        break;<a name="line.187"></a>
<FONT color="green">188</FONT>                    }<a name="line.188"></a>
<FONT color="green">189</FONT>                }<a name="line.189"></a>
<FONT color="green">190</FONT>            } catch (ClassNotFoundException cnfe) {<a name="line.190"></a>
<FONT color="green">191</FONT>                logger.debug("sun.reflect.Reflection is not installed");<a name="line.191"></a>
<FONT color="green">192</FONT>            }<a name="line.192"></a>
<FONT color="green">193</FONT>            try {<a name="line.193"></a>
<FONT color="green">194</FONT>                securityManager = new PrivateSecurityManager();<a name="line.194"></a>
<FONT color="green">195</FONT>            } catch (Exception ex) {<a name="line.195"></a>
<FONT color="green">196</FONT>                ex.printStackTrace();<a name="line.196"></a>
<FONT color="green">197</FONT>                logger.debug("Unable to install security manager", ex);<a name="line.197"></a>
<FONT color="green">198</FONT>            }<a name="line.198"></a>
<FONT color="green">199</FONT>        }<a name="line.199"></a>
<FONT color="green">200</FONT>    <a name="line.200"></a>
<FONT color="green">201</FONT>        private LoggerContext getDefault() {<a name="line.201"></a>
<FONT color="green">202</FONT>            LoggerContext ctx = context.get();<a name="line.202"></a>
<FONT color="green">203</FONT>            if (ctx != null) {<a name="line.203"></a>
<FONT color="green">204</FONT>                return ctx;<a name="line.204"></a>
<FONT color="green">205</FONT>            }<a name="line.205"></a>
<FONT color="green">206</FONT>            context.compareAndSet(null, new LoggerContext("Default"));<a name="line.206"></a>
<FONT color="green">207</FONT>            return context.get();<a name="line.207"></a>
<FONT color="green">208</FONT>        }<a name="line.208"></a>
<FONT color="green">209</FONT>    <a name="line.209"></a>
<FONT color="green">210</FONT>        /**<a name="line.210"></a>
<FONT color="green">211</FONT>         * SecurityManager that will locate the caller of the Log4j2 API.<a name="line.211"></a>
<FONT color="green">212</FONT>         */<a name="line.212"></a>
<FONT color="green">213</FONT>        private static class PrivateSecurityManager extends SecurityManager {<a name="line.213"></a>
<FONT color="green">214</FONT>    <a name="line.214"></a>
<FONT color="green">215</FONT>            public Class getCaller(String fqcn) {<a name="line.215"></a>
<FONT color="green">216</FONT>                Class[] classes = getClassContext();<a name="line.216"></a>
<FONT color="green">217</FONT>                boolean next = false;<a name="line.217"></a>
<FONT color="green">218</FONT>                for (Class clazz : classes) {<a name="line.218"></a>
<FONT color="green">219</FONT>                    if (clazz.getName().equals(fqcn)) {<a name="line.219"></a>
<FONT color="green">220</FONT>                        next = true;<a name="line.220"></a>
<FONT color="green">221</FONT>                        continue;<a name="line.221"></a>
<FONT color="green">222</FONT>                    }<a name="line.222"></a>
<FONT color="green">223</FONT>                    if (next) {<a name="line.223"></a>
<FONT color="green">224</FONT>                        return clazz;<a name="line.224"></a>
<FONT color="green">225</FONT>                    }<a name="line.225"></a>
<FONT color="green">226</FONT>                }<a name="line.226"></a>
<FONT color="green">227</FONT>                return null;<a name="line.227"></a>
<FONT color="green">228</FONT>            }<a name="line.228"></a>
<FONT color="green">229</FONT>        }<a name="line.229"></a>
<FONT color="green">230</FONT>    <a name="line.230"></a>
<FONT color="green">231</FONT>    }<a name="line.231"></a>


</PRE>
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