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.lookup;
018
019import java.text.DateFormat;
020import java.text.SimpleDateFormat;
021import java.util.Date;
022
023import org.apache.logging.log4j.Logger;
024import org.apache.logging.log4j.Marker;
025import org.apache.logging.log4j.MarkerManager;
026import org.apache.logging.log4j.core.LogEvent;
027import org.apache.logging.log4j.core.config.plugins.Plugin;
028import org.apache.logging.log4j.status.StatusLogger;
029
030/**
031 * Formats the current date or the date in the LogEvent. The "key" is used as the format String.
032 */
033@Plugin(name = "date", category = StrLookup.CATEGORY)
034public class DateLookup implements StrLookup {
035
036    private static final Logger LOGGER = StatusLogger.getLogger();
037    private static final Marker LOOKUP = MarkerManager.getMarker("LOOKUP");
038
039    /**
040     * Looks up the value of the environment variable.
041     * @param key the format to use. If null, the default DateFormat will be used.
042     * @return The value of the environment variable.
043     */
044    @Override
045    public String lookup(final String key) {
046        return formatDate(System.currentTimeMillis(), key);
047    }
048
049    /**
050     * Looks up the value of the environment variable.
051     * @param event The current LogEvent (is ignored by this StrLookup).
052     * @param key the format to use. If null, the default DateFormat will be used.
053     * @return The value of the environment variable.
054     */
055    @Override
056    public String lookup(final LogEvent event, final String key) {
057        return formatDate(event.getTimeMillis(), key);
058    }
059
060    private String formatDate(final long date, final String format) {
061        DateFormat dateFormat = null;
062        if (format != null) {
063            try {
064                dateFormat = new SimpleDateFormat(format);
065            } catch (final Exception ex) {
066                LOGGER.error(LOOKUP, "Invalid date format: [{}], using default", format, ex);
067            }
068        }
069        if (dateFormat == null) {
070            dateFormat = DateFormat.getInstance();
071        }
072        return dateFormat.format(new Date(date));
073    }
074}