    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.core.pattern;
    018
    019    /**
    020     * Interface that all PatternConverters must implement.
    021     */
    022    public 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    }