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.spi;
018    
019    import org.apache.logging.log4j.Logger;
020    import org.apache.logging.log4j.message.MessageFactory;
021    
022    /**
023     * Anchor point for logging implementations.
024     */
025    public interface LoggerContext {
026    
027        /**
028         * An anchor for some other context, such as a ServletContext.
029         * @return The external context.
030         */
031        Object getExternalContext();
032    
033        /**
034         * Returns a Logger.
035         * @param name The name of the Logger to return.
036         * @return The logger with the specified name.
037         */
038        Logger getLogger(String name);
039    
040        /**
041         * Returns a Logger.
042         * @param name The name of the Logger to return.
043         * @param messageFactory The message factory is used only when creating a logger, subsequent use does not change
044         *                       the logger but will log a warning if mismatched.
045         * @return The logger with the specified name.
046         */
047        Logger getLogger(String name, MessageFactory messageFactory);
048    
049        /**
050         * Detects if a Logger with the specified name exists.
051         * @param name The Logger name to search for.
052         * @return true if the Logger exists, false otherwise.
053         */
054        boolean hasLogger(String name);
055    
056    }