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 */
017package org.apache.logging.log4j.spi;
018
019import org.apache.logging.log4j.message.MessageFactory;
020
021/**
022 * Anchor point for logging implementations.
023 */
024public interface LoggerContext {
025
026    /**
027     * An anchor for some other context, such as a ServletContext.
028     * @return The external context.
029     */
030    Object getExternalContext();
031
032    /**
033     * Returns a Logger.
034     * @param name The name of the Logger to return.
035     * @return The logger with the specified name.
036     */
037    ExtendedLogger getLogger(String name);
038
039    /**
040     * Returns a Logger.
041     * @param name The name of the Logger to return.
042     * @param messageFactory The message factory is used only when creating a logger, subsequent use does not change
043     *                       the logger but will log a warning if mismatched.
044     * @return The logger with the specified name.
045     */
046    ExtendedLogger getLogger(String name, MessageFactory messageFactory);
047
048    /**
049     * Detects if a Logger with the specified name exists.
050     * @param name The Logger name to search for.
051     * @return true if the Logger exists, false otherwise.
052     */
053    boolean hasLogger(String name);
054}