001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache license, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the license for the specific language governing permissions and 015 * limitations under the license. 016 */ 017 package org.apache.logging.log4j.core.web; 018 019 import org.apache.logging.log4j.core.config.Configurator; 020 import org.apache.logging.log4j.core.LoggerContext; 021 022 import javax.servlet.ServletContext; 023 import javax.servlet.ServletContextEvent; 024 import javax.servlet.ServletContextListener; 025 import java.lang.reflect.Method; 026 027 /** 028 * Saves the LoggerContext into the ServletContext as an attribute. 029 */ 030 public class Log4jContextListener implements ServletContextListener { 031 032 /** 033 * The name of the attribute to use to store the LoggerContext into the ServletContext. 034 */ 035 public static final String LOG4J_CONTEXT_ATTRIBUTE = "Log4JContext"; 036 037 /** 038 * The location of the configuration. 039 */ 040 public static final String LOG4J_CONFIG = "log4jConfiguration"; 041 042 /** 043 * The name of the LoggerContext. 044 */ 045 public static final String LOG4J_CONTEXT_NAME = "log4jContextName"; 046 047 /** 048 * Initialize Logging for the web application. 049 * @param event The ServletContextEvent. 050 */ 051 public void contextInitialized(final ServletContextEvent event) { 052 final ServletContext context = event.getServletContext(); 053 final String locn = context.getInitParameter(LOG4J_CONFIG); 054 String name = context.getInitParameter(LOG4J_CONTEXT_NAME); 055 if (name == null) { 056 name = context.getServletContextName(); 057 } 058 if (name == null && locn == null) { 059 context.log("No Log4j context configuration provided"); 060 return; 061 } 062 context.setAttribute(LOG4J_CONTEXT_ATTRIBUTE, Configurator.initialize(name, getClassLoader(context), locn)); 063 } 064 065 /** 066 * Shutdown logging for the web application. 067 * @param event The ServletContextEvent. 068 */ 069 public void contextDestroyed(final ServletContextEvent event) { 070 final LoggerContext ctx = (LoggerContext) event.getServletContext().getAttribute(LOG4J_CONTEXT_ATTRIBUTE); 071 Configurator.shutdown(ctx); 072 } 073 074 private ClassLoader getClassLoader(final ServletContext context) { 075 final Method[] methods = context.getClass().getMethods(); 076 Method getClassLoader = null; 077 for (final Method method : methods) { 078 if (method.getName().equals("getClassLoader")) { 079 getClassLoader = method; 080 break; 081 } 082 } 083 084 if (getClassLoader != null) { 085 try { 086 return (ClassLoader) getClassLoader.invoke(context, null); 087 } catch (final Exception ex) { 088 // Ignore the exception 089 } 090 } 091 092 return Log4jContextListener.class.getClassLoader(); 093 } 094 }