    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    }