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
019import java.util.UUID;
020
021import org.apache.logging.log4j.core.LogEvent;
022import org.apache.logging.log4j.core.config.plugins.Plugin;
023import 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" })
030public 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}