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
018package org.apache.logging.log4j.jul;
019
020import org.apache.logging.log4j.Level;
021import org.apache.logging.log4j.Logger;
022import org.apache.logging.log4j.status.StatusLogger;
023import org.apache.logging.log4j.util.LoaderUtil;
024import org.apache.logging.log4j.util.PropertiesUtil;
025
026/**
027 * Utility class to convert between JDK Levels and Log4j 2 Levels.
028 *
029 * @since 2.1
030 */
031public final class LevelTranslator {
032
033    /**
034     * Custom Log4j level corresponding to the {@link java.util.logging.Level#FINEST} logging level. This maps to a
035     * level more specific than {@link org.apache.logging.log4j.Level#TRACE}.
036     */
037    public static final Level FINEST = Level.forName("FINEST", Level.TRACE.intLevel() + 100);
038
039    /**
040     * Custom Log4j level corresponding to the {@link java.util.logging.Level#CONFIG} logging level. This maps to a
041     * level in between {@link org.apache.logging.log4j.Level#INFO} and {@link org.apache.logging.log4j.Level#DEBUG}.
042     */
043    public static final Level CONFIG = Level.forName("CONFIG", Level.INFO.intLevel() + 50);
044
045    private static final Logger LOGGER = StatusLogger.getLogger();
046    private static final LevelConverter LEVEL_CONVERTER;
047
048    static {
049        final String levelConverterClassName =
050            PropertiesUtil.getProperties().getStringProperty(Constants.LEVEL_CONVERTER_PROPERTY);
051        if (levelConverterClassName != null) {
052            LevelConverter levelConverter;
053            try {
054                levelConverter = LoaderUtil.newCheckedInstanceOf(levelConverterClassName, LevelConverter.class);
055            } catch (final Exception e) {
056                LOGGER.error("Could not create custom LevelConverter [{}].", levelConverterClassName, e);
057                levelConverter = new DefaultLevelConverter();
058            }
059            LEVEL_CONVERTER = levelConverter;
060        } else {
061            LEVEL_CONVERTER = new DefaultLevelConverter();
062        }
063    }
064
065    /**
066     * Converts a JDK logging Level to a Log4j logging Level.
067     *
068     * @param level JDK Level to convert, may be null per the JUL specification.
069     * @return converted Level or null
070     */
071    public static Level toLevel(final java.util.logging.Level level) {
072        return LEVEL_CONVERTER.toLevel(level);
073    }
074
075    /**
076     * Converts a Log4j logging Level to a JDK logging Level.
077     *
078     * @param level Log4j Level to convert.
079     * @return converted Level.
080     */
081    public static java.util.logging.Level toJavaLevel(final Level level) {
082        return LEVEL_CONVERTER.toJavaLevel(level);
083    }
084
085    private LevelTranslator() {
086    }
087}