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.core.pattern;
018
019/**
020 * Interface that all PatternConverters must implement.
021 */
022public interface PatternConverter {
023
024    /**
025     * Main plugin category for PatternConverter plugins.
026     *
027     * @since 2.1
028     */
029    String CATEGORY = "Converter";
030
031    /**
032     * Formats an object into a string buffer.
033     *
034     * @param obj        event to format, may not be null.
035     * @param toAppendTo string buffer to which the formatted event will be appended.  May not be null.
036     */
037    void format(Object obj, StringBuilder toAppendTo);
038
039    /**
040     * Returns the name of the converter.
041     * @return The name of the converter.
042     */
043    String getName();
044
045    /**
046     * This method returns the CSS style class that should be applied to
047     * the LoggingEvent passed as parameter, which can be null.
048     *
049     * @param e null values are accepted
050     * @return the name of the conversion pattern
051     */
052    String getStyleClass(Object e);
053}