    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    import java.util.UUID;
    020
    021    import org.apache.logging.log4j.core.LogEvent;
    022    import org.apache.logging.log4j.core.config.plugins.Plugin;
    023    import org.apache.logging.log4j.core.util.UuidUtil;
    024
    025    /**
    026     * Formats the event sequence number.
    027     */
    028    @Plugin(name = "UuidPatternConverter", category = PatternConverter.CATEGORY)
    029    @ConverterKeys({ "u", "uuid" })
    030    public final class UuidPatternConverter extends LogEventPatternConverter {
    031
    032        private final boolean isRandom;
    033
    034        /**
    035         * Private constructor.
    036         */
    037        private UuidPatternConverter(final boolean isRandom) {
    038            super("u", "uuid");
    039            this.isRandom = isRandom;
    040        }
    041
    042        /**
    043         * Obtains an instance of SequencePatternConverter.
    044         *
    045         * @param options options, currently ignored, may be null.
    046         * @return instance of SequencePatternConverter.
    047         */
    048        public static UuidPatternConverter newInstance(final String[] options) {
    049            if (options.length == 0) {
    050                return new UuidPatternConverter(false);
    051            }
    052
    053            if (options.length > 1 || (!options[0].equalsIgnoreCase("RANDOM") && !options[0].equalsIgnoreCase("Time"))) {
    054                LOGGER.error("UUID Pattern Converter only accepts a single option with the value \"RANDOM\" or \"TIME\"");
    055            }
    056            return new UuidPatternConverter(options[0].equalsIgnoreCase("RANDOM"));
    057        }
    058
    059        /**
    060         * {@inheritDoc}
    061         */
    062        @Override
    063        public void format(final LogEvent event, final StringBuilder toAppendTo) {
    064            final UUID uuid = isRandom ? UUID.randomUUID() : UuidUtil.getTimeBasedUuid();
    065            toAppendTo.append(uuid.toString());
    066        }
    067    }