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.impl; 018 019 import org.apache.logging.log4j.core.LoggerContext; 020 import org.apache.logging.log4j.core.helpers.Constants; 021 import org.apache.logging.log4j.core.helpers.Loader; 022 import org.apache.logging.log4j.core.selector.ClassLoaderContextSelector; 023 import org.apache.logging.log4j.core.selector.ContextSelector; 024 import org.apache.logging.log4j.status.StatusLogger; 025 import org.apache.logging.log4j.spi.LoggerContextFactory; 026 027 /** 028 * Factory to locate a ContextSelector and then load a LoggerContext. 029 */ 030 public class Log4jContextFactory implements LoggerContextFactory { 031 032 private static final StatusLogger logger = StatusLogger.getLogger(); 033 034 private ContextSelector selector; 035 036 /** 037 * Constructor that initializes the ContextSelector. 038 */ 039 public Log4jContextFactory() { 040 String sel = System.getProperty(Constants.LOG4J_CONTEXT_SELECTOR); 041 if (sel != null) { 042 try { 043 Class clazz = Loader.loadClass(sel); 044 if (clazz != null && ContextSelector.class.isAssignableFrom(clazz)) { 045 selector = (ContextSelector) clazz.newInstance(); 046 return; 047 } 048 } catch (Exception ex) { 049 logger.error("Unable to create context " + sel, ex); 050 } 051 052 } 053 selector = new ClassLoaderContextSelector(); 054 } 055 056 /** 057 * Returns the ContextSelector. 058 * @return The ContextSelector. 059 */ 060 public ContextSelector getSelector() { 061 return selector; 062 } 063 064 /** 065 * Load the LoggerContext using the ContextSelector. 066 * @param fqcn The fully qualified class name of the caller. 067 * @param loader The ClassLoader to use or null. 068 * @param currentContext If true returns the current Context, if false returns the Context appropriate 069 * for the caller if a more appropriate Context can be determined. 070 * @return The LoggerContext. 071 */ 072 public LoggerContext getContext(String fqcn, ClassLoader loader, boolean currentContext) { 073 LoggerContext ctx = selector.getContext(fqcn, loader, currentContext); 074 if (ctx.getStatus() == LoggerContext.Status.INITIALIZED) { 075 ctx.start(); 076 } 077 return ctx; 078 } 079 }