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.slf4j;
018    
019    import java.net.URI;
020    
021    import org.apache.logging.log4j.spi.LoggerContext;
022    import org.apache.logging.log4j.spi.LoggerContextFactory;
023    import org.apache.logging.log4j.status.StatusLogger;
024    
025    /**
026     *
027     */
028    public class SLF4JLoggerContextFactory implements LoggerContextFactory {
029        private static final StatusLogger LOGGER = StatusLogger.getLogger();
030        private static LoggerContext context = new SLF4JLoggerContext();
031    
032        public SLF4JLoggerContextFactory() {
033            // LOG4J2-230, LOG4J2-204 (improve error reporting when misconfigured)
034            boolean misconfigured = false;
035            try {
036                Class.forName("org.slf4j.helpers.Log4jLoggerFactory");
037                misconfigured = true;
038            } catch (final ClassNotFoundException classNotFoundIsGood) {
039                LOGGER.debug("org.slf4j.helpers.Log4jLoggerFactory is not on classpath. Good!");
040            }
041            if (misconfigured) {
042                throw new IllegalStateException("slf4j-impl jar is mutually exclusive with log4j-to-slf4j jar "
043                        + "(the first routes calls from SLF4J to Log4j, the second from Log4j to SLF4J)");
044            }
045        }
046    
047        @Override
048        public LoggerContext getContext(final String fqcn, final ClassLoader loader, final Object externalContext,
049                                        final boolean currentContext) {
050            return context;
051        }
052    
053        @Override
054        public LoggerContext getContext(final String fqcn, final ClassLoader loader, final Object externalContext,
055                                        final boolean currentContext, final URI configLocation, final String name) {
056            return context;
057        }
058    
059        @Override
060        public void removeContext(final LoggerContext context) {
061        }
062    }