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     * Formats an object into a string buffer.
025     *
026     * @param obj        event to format, may not be null.
027     * @param toAppendTo string buffer to which the formatted event will be appended.  May not be null.
028     */
029    void format(Object obj, StringBuilder toAppendTo);
030
031    /**
032     * Returns the name of the converter.
033     * @return The name of the converter.
034     */
035    String getName();
036
037    /**
038     * This method returns the CSS style class that should be applied to
039     * the LoggingEvent passed as parameter, which can be null.
040     * <p/>
041     *
042     * @param e null values are accepted
043     * @return the name of the conversion pattern
044     */
045    String getStyleClass(Object e);
046}