Google Git
Sign in
apache / logging-log4j-site / d0d0de55986756593c08e5d2b8059541eacaf428 / . / log4j-2.0-alpha1-SNAPSHOT / log4j-api / apidocs / src-html / org / apache / logging / log4j / LogManager.html
blob: ab86b7a0d3c6f563f5a3724cc200b2b2851394e9 [file] [log] [blame]
<HTML>
<BODY BGCOLOR="white">
<PRE>
<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;<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.status.StatusLogger;<a name="line.19"></a>
<FONT color="green">020</FONT> import org.apache.logging.log4j.spi.LoggerContext;<a name="line.20"></a>
<FONT color="green">021</FONT> import org.apache.logging.log4j.spi.LoggerContextFactory;<a name="line.21"></a>
<FONT color="green">022</FONT> <a name="line.22"></a>
<FONT color="green">023</FONT> import java.io.IOException;<a name="line.23"></a>
<FONT color="green">024</FONT> import java.net.URL;<a name="line.24"></a>
<FONT color="green">025</FONT> import java.util.ArrayList;<a name="line.25"></a>
<FONT color="green">026</FONT> import java.util.Enumeration;<a name="line.26"></a>
<FONT color="green">027</FONT> import java.util.List;<a name="line.27"></a>
<FONT color="green">028</FONT> import java.util.Properties;<a name="line.28"></a>
<FONT color="green">029</FONT> <a name="line.29"></a>
<FONT color="green">030</FONT> /**<a name="line.30"></a>
<FONT color="green">031</FONT> * The anchor point for the logging system.<a name="line.31"></a>
<FONT color="green">032</FONT> */<a name="line.32"></a>
<FONT color="green">033</FONT> public class LogManager {<a name="line.33"></a>
<FONT color="green">034</FONT> /**<a name="line.34"></a>
<FONT color="green">035</FONT> * The name of the root Logger.<a name="line.35"></a>
<FONT color="green">036</FONT> */<a name="line.36"></a>
<FONT color="green">037</FONT> public static final String ROOT_LOGGER_NAME = "";<a name="line.37"></a>
<FONT color="green">038</FONT> <a name="line.38"></a>
<FONT color="green">039</FONT> private static final String LOGGER_RESOURCE = "META-INF/log4j-provider.xml";<a name="line.39"></a>
<FONT color="green">040</FONT> private static final String LOGGER_CONTEXT_FACTORY = "LoggerContextFactory";<a name="line.40"></a>
<FONT color="green">041</FONT> private static final String API_VERSION = "Log4jAPIVersion";<a name="line.41"></a>
<FONT color="green">042</FONT> private static final String[] COMPATIBLE_API_VERSIONS = {<a name="line.42"></a>
<FONT color="green">043</FONT> "1.99.0"<a name="line.43"></a>
<FONT color="green">044</FONT> };<a name="line.44"></a>
<FONT color="green">045</FONT> <a name="line.45"></a>
<FONT color="green">046</FONT> private static LoggerContextFactory factory;<a name="line.46"></a>
<FONT color="green">047</FONT> <a name="line.47"></a>
<FONT color="green">048</FONT> private static Logger logger = StatusLogger.getLogger();<a name="line.48"></a>
<FONT color="green">049</FONT> <a name="line.49"></a>
<FONT color="green">050</FONT> /**<a name="line.50"></a>
<FONT color="green">051</FONT> * Prevent instantiation<a name="line.51"></a>
<FONT color="green">052</FONT> */<a name="line.52"></a>
<FONT color="green">053</FONT> protected LogManager() {<a name="line.53"></a>
<FONT color="green">054</FONT> }<a name="line.54"></a>
<FONT color="green">055</FONT> <a name="line.55"></a>
<FONT color="green">056</FONT> <a name="line.56"></a>
<FONT color="green">057</FONT> /**<a name="line.57"></a>
<FONT color="green">058</FONT> * Scans the classpath to find all logging implementation. Currently, only one will<a name="line.58"></a>
<FONT color="green">059</FONT> * be used but this could be extended to allow multiple implementations to be used.<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> ClassLoader cl = findClassLoader();<a name="line.62"></a>
<FONT color="green">063</FONT> List&lt;LoggerContextFactory&gt; factories = new ArrayList&lt;LoggerContextFactory&gt;();<a name="line.63"></a>
<FONT color="green">064</FONT> <a name="line.64"></a>
<FONT color="green">065</FONT> Enumeration enumResources = null;<a name="line.65"></a>
<FONT color="green">066</FONT> try {<a name="line.66"></a>
<FONT color="green">067</FONT> enumResources = cl.getResources(LOGGER_RESOURCE);<a name="line.67"></a>
<FONT color="green">068</FONT> } catch (IOException e) {<a name="line.68"></a>
<FONT color="green">069</FONT> logger.fatal("Unable to locate " + LOGGER_RESOURCE, e);<a name="line.69"></a>
<FONT color="green">070</FONT> }<a name="line.70"></a>
<FONT color="green">071</FONT> <a name="line.71"></a>
<FONT color="green">072</FONT> if (enumResources != null) {<a name="line.72"></a>
<FONT color="green">073</FONT> while (enumResources.hasMoreElements()) {<a name="line.73"></a>
<FONT color="green">074</FONT> Properties props = new Properties();<a name="line.74"></a>
<FONT color="green">075</FONT> URL url = (URL) enumResources.nextElement();<a name="line.75"></a>
<FONT color="green">076</FONT> try {<a name="line.76"></a>
<FONT color="green">077</FONT> props.loadFromXML(url.openStream());<a name="line.77"></a>
<FONT color="green">078</FONT> } catch (IOException ioe) {<a name="line.78"></a>
<FONT color="green">079</FONT> logger.error("Unable to read " + url.toString(), ioe);<a name="line.79"></a>
<FONT color="green">080</FONT> }<a name="line.80"></a>
<FONT color="green">081</FONT> if (!validVersion(props.getProperty(API_VERSION))) {<a name="line.81"></a>
<FONT color="green">082</FONT> continue;<a name="line.82"></a>
<FONT color="green">083</FONT> }<a name="line.83"></a>
<FONT color="green">084</FONT> String className = props.getProperty(LOGGER_CONTEXT_FACTORY);<a name="line.84"></a>
<FONT color="green">085</FONT> if (className != null) {<a name="line.85"></a>
<FONT color="green">086</FONT> try {<a name="line.86"></a>
<FONT color="green">087</FONT> Class clazz = cl.loadClass(className);<a name="line.87"></a>
<FONT color="green">088</FONT> if (LoggerContextFactory.class.isAssignableFrom(clazz)) {<a name="line.88"></a>
<FONT color="green">089</FONT> factories.add((LoggerContextFactory) clazz.newInstance());<a name="line.89"></a>
<FONT color="green">090</FONT> } else {<a name="line.90"></a>
<FONT color="green">091</FONT> logger.error(className + " does not implement " + LoggerContextFactory.class.getName());<a name="line.91"></a>
<FONT color="green">092</FONT> }<a name="line.92"></a>
<FONT color="green">093</FONT> } catch (ClassNotFoundException cnfe) {<a name="line.93"></a>
<FONT color="green">094</FONT> logger.error("Unable to locate class " + className + " specified in " + url.toString(), cnfe);<a name="line.94"></a>
<FONT color="green">095</FONT> } catch (IllegalAccessException iae) {<a name="line.95"></a>
<FONT color="green">096</FONT> logger.error("Unable to create class " + className + " specified in " + url.toString(), iae);<a name="line.96"></a>
<FONT color="green">097</FONT> } catch (Exception e) {<a name="line.97"></a>
<FONT color="green">098</FONT> logger.error("Unable to create class " + className + " specified in " + url.toString(), e);<a name="line.98"></a>
<FONT color="green">099</FONT> e.printStackTrace();<a name="line.99"></a>
<FONT color="green">100</FONT> }<a name="line.100"></a>
<FONT color="green">101</FONT> }<a name="line.101"></a>
<FONT color="green">102</FONT> }<a name="line.102"></a>
<FONT color="green">103</FONT> if (factories.size() != 1) {<a name="line.103"></a>
<FONT color="green">104</FONT> logger.fatal("Unable to locate a logging implementation");<a name="line.104"></a>
<FONT color="green">105</FONT> } else {<a name="line.105"></a>
<FONT color="green">106</FONT> factory = factories.get(0);<a name="line.106"></a>
<FONT color="green">107</FONT> }<a name="line.107"></a>
<FONT color="green">108</FONT> } else {<a name="line.108"></a>
<FONT color="green">109</FONT> logger.fatal("Unable to locate a logging implementation");<a name="line.109"></a>
<FONT color="green">110</FONT> }<a name="line.110"></a>
<FONT color="green">111</FONT> }<a name="line.111"></a>
<FONT color="green">112</FONT> <a name="line.112"></a>
<FONT color="green">113</FONT> /**<a name="line.113"></a>
<FONT color="green">114</FONT> * Return the LoggerContextFactory.<a name="line.114"></a>
<FONT color="green">115</FONT> * @return The LoggerContextFactory.<a name="line.115"></a>
<FONT color="green">116</FONT> */<a name="line.116"></a>
<FONT color="green">117</FONT> public static LoggerContextFactory getFactory() {<a name="line.117"></a>
<FONT color="green">118</FONT> return factory;<a name="line.118"></a>
<FONT color="green">119</FONT> }<a name="line.119"></a>
<FONT color="green">120</FONT> <a name="line.120"></a>
<FONT color="green">121</FONT> /**<a name="line.121"></a>
<FONT color="green">122</FONT> * Return a Logger with the specified name.<a name="line.122"></a>
<FONT color="green">123</FONT> *<a name="line.123"></a>
<FONT color="green">124</FONT> * @param name The logger name.<a name="line.124"></a>
<FONT color="green">125</FONT> * @return The Logger.<a name="line.125"></a>
<FONT color="green">126</FONT> */<a name="line.126"></a>
<FONT color="green">127</FONT> public static Logger getLogger(String name) {<a name="line.127"></a>
<FONT color="green">128</FONT> <a name="line.128"></a>
<FONT color="green">129</FONT> return factory.getContext(LogManager.class.getName(), false).getLogger(name);<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> * Return a Logger with the specified name.<a name="line.133"></a>
<FONT color="green">134</FONT> *<a name="line.134"></a>
<FONT color="green">135</FONT> * @param fqcn The fully qualified class name of the class that this method is a member of.<a name="line.135"></a>
<FONT color="green">136</FONT> * @param name The logger name.<a name="line.136"></a>
<FONT color="green">137</FONT> * @return The Logger.<a name="line.137"></a>
<FONT color="green">138</FONT> */<a name="line.138"></a>
<FONT color="green">139</FONT> protected static Logger getLogger(String fqcn, String name) {<a name="line.139"></a>
<FONT color="green">140</FONT> <a name="line.140"></a>
<FONT color="green">141</FONT> return factory.getContext(fqcn, false).getLogger(name);<a name="line.141"></a>
<FONT color="green">142</FONT> }<a name="line.142"></a>
<FONT color="green">143</FONT> <a name="line.143"></a>
<FONT color="green">144</FONT> /**<a name="line.144"></a>
<FONT color="green">145</FONT> * Returns the current LoggerContext.<a name="line.145"></a>
<FONT color="green">146</FONT> * &lt;p&gt;<a name="line.146"></a>
<FONT color="green">147</FONT> * WARNING - The LoggerContext returned by this method may not be the LoggerContext used to create a Logger<a name="line.147"></a>
<FONT color="green">148</FONT> * for the calling class.<a name="line.148"></a>
<FONT color="green">149</FONT> * @return The current LoggerContext.<a name="line.149"></a>
<FONT color="green">150</FONT> */<a name="line.150"></a>
<FONT color="green">151</FONT> public static LoggerContext getContext() {<a name="line.151"></a>
<FONT color="green">152</FONT> return factory.getContext(LogManager.class.getName(), true);<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> /**<a name="line.155"></a>
<FONT color="green">156</FONT> * Returns a LoggerContext.<a name="line.156"></a>
<FONT color="green">157</FONT> *<a name="line.157"></a>
<FONT color="green">158</FONT> * @param currentContext if false the LoggerContext appropriate for the caller of this method is returned. For<a name="line.158"></a>
<FONT color="green">159</FONT> * example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be<a name="line.159"></a>
<FONT color="green">160</FONT> * returned and if the caller is a class in the container's classpath then a different LoggerContext may be<a name="line.160"></a>
<FONT color="green">161</FONT> * returned. If true then only a single LoggerContext will be returned.<a name="line.161"></a>
<FONT color="green">162</FONT> * @return a LoggerContext.<a name="line.162"></a>
<FONT color="green">163</FONT> */<a name="line.163"></a>
<FONT color="green">164</FONT> public static LoggerContext getContext(boolean currentContext) {<a name="line.164"></a>
<FONT color="green">165</FONT> return factory.getContext(LogManager.class.getName(), currentContext);<a name="line.165"></a>
<FONT color="green">166</FONT> }<a name="line.166"></a>
<FONT color="green">167</FONT> <a name="line.167"></a>
<FONT color="green">168</FONT> /**<a name="line.168"></a>
<FONT color="green">169</FONT> * Returns a LoggerContext<a name="line.169"></a>
<FONT color="green">170</FONT> * @param fqcn The fully qualified class name of the Class that this method is a member of.<a name="line.170"></a>
<FONT color="green">171</FONT> * @param currentContext if false the LoggerContext appropriate for the caller of this method is returned. For<a name="line.171"></a>
<FONT color="green">172</FONT> * example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be<a name="line.172"></a>
<FONT color="green">173</FONT> * returned and if the caller is a class in the container's classpath then a different LoggerContext may be<a name="line.173"></a>
<FONT color="green">174</FONT> * returned. If true then only a single LoggerContext will be returned.<a name="line.174"></a>
<FONT color="green">175</FONT> * @return a LoggerContext.<a name="line.175"></a>
<FONT color="green">176</FONT> */<a name="line.176"></a>
<FONT color="green">177</FONT> protected static LoggerContext getContext(String fqcn, boolean currentContext) {<a name="line.177"></a>
<FONT color="green">178</FONT> return factory.getContext(fqcn, currentContext);<a name="line.178"></a>
<FONT color="green">179</FONT> }<a name="line.179"></a>
<FONT color="green">180</FONT> <a name="line.180"></a>
<FONT color="green">181</FONT> private static ClassLoader findClassLoader() {<a name="line.181"></a>
<FONT color="green">182</FONT> ClassLoader cl;<a name="line.182"></a>
<FONT color="green">183</FONT> if (System.getSecurityManager() == null) {<a name="line.183"></a>
<FONT color="green">184</FONT> cl = Thread.currentThread().getContextClassLoader();<a name="line.184"></a>
<FONT color="green">185</FONT> } else {<a name="line.185"></a>
<FONT color="green">186</FONT> cl = (ClassLoader) java.security.AccessController.doPrivileged(<a name="line.186"></a>
<FONT color="green">187</FONT> new java.security.PrivilegedAction() {<a name="line.187"></a>
<FONT color="green">188</FONT> public Object run() {<a name="line.188"></a>
<FONT color="green">189</FONT> return Thread.currentThread().getContextClassLoader();<a name="line.189"></a>
<FONT color="green">190</FONT> }<a name="line.190"></a>
<FONT color="green">191</FONT> }<a name="line.191"></a>
<FONT color="green">192</FONT> );<a name="line.192"></a>
<FONT color="green">193</FONT> }<a name="line.193"></a>
<FONT color="green">194</FONT> if (cl == null) {<a name="line.194"></a>
<FONT color="green">195</FONT> cl = LogManager.class.getClassLoader();<a name="line.195"></a>
<FONT color="green">196</FONT> }<a name="line.196"></a>
<FONT color="green">197</FONT> <a name="line.197"></a>
<FONT color="green">198</FONT> return cl;<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 static boolean validVersion(String version) {<a name="line.201"></a>
<FONT color="green">202</FONT> for (String v : COMPATIBLE_API_VERSIONS) {<a name="line.202"></a>
<FONT color="green">203</FONT> if (version.startsWith(v)) {<a name="line.203"></a>
<FONT color="green">204</FONT> return true;<a name="line.204"></a>
<FONT color="green">205</FONT> }<a name="line.205"></a>
<FONT color="green">206</FONT> }<a name="line.206"></a>
<FONT color="green">207</FONT> return false;<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> <a name="line.211"></a>
<FONT color="green">212</FONT> }<a name="line.212"></a>
</PRE>
</BODY>
</HTML>