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
018package org.apache.logging.log4j.core.config;
019
020import org.apache.logging.log4j.Level;
021import org.apache.logging.log4j.Marker;
022import org.apache.logging.log4j.core.LogEvent;
023import org.apache.logging.log4j.message.Message;
024import org.apache.logging.log4j.util.Supplier;
025
026/**
027 * Interface for objects that know how to ensure delivery of log events to the appropriate appenders, even during and
028 * after the configuration has been modified while the system is actively used.
029 */
030public interface ReliabilityStrategy {
031
032    /**
033     * Logs an event.
034     *
035     * @param reconfigured supplies the next LoggerConfig if the strategy's LoggerConfig is no longer active
036     * @param loggerName The name of the Logger.
037     * @param fqcn The fully qualified class name of the caller.
038     * @param marker A Marker or null if none is present.
039     * @param level The event Level.
040     * @param data The Message.
041     * @param t A Throwable or null.
042     */
043    void log(Supplier<LoggerConfig> reconfigured, String loggerName, String fqcn, Marker marker, Level level,
044            Message data, Throwable t);
045
046    /**
047     * Logs an event.
048     *
049     * @param reconfigured supplies the next LoggerConfig if the strategy's LoggerConfig is no longer active
050     * @param event The log event.
051     */
052    void log(Supplier<LoggerConfig> reconfigured, LogEvent event);
053
054    /**
055     * For internal use by the ReliabilityStrategy; returns the LoggerConfig to use.
056     * 
057     * @param next supplies the next LoggerConfig if the strategy's LoggerConfig is no longer active
058     * @return the currently active LoggerConfig
059     */
060    LoggerConfig getActiveLoggerConfig(Supplier<LoggerConfig> next);
061
062    /**
063     * Called after a log event was logged.
064     */
065    void afterLogEvent();
066
067    /**
068     * Called before all appenders are stopped.
069     */
070    void beforeStopAppenders();
071
072    /**
073     * Called before the configuration is stopped.
074     * 
075     * @param configuration the configuration that will be stopped
076     */
077    void beforeStopConfiguration(Configuration configuration);
078
079}