001/**
002 * Logback: the reliable, generic, fast and flexible logging framework.
003 * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
004 *
005 * This program and the accompanying materials are dual-licensed under
006 * either the terms of the Eclipse Public License v1.0 as published by
007 * the Eclipse Foundation
008 *
009 *   or (per the licensee's choosing)
010 *
011 * under the terms of the GNU Lesser General Public License version 2.1
012 * as published by the Free Software Foundation.
013 */
014package ch.qos.logback.classic.pattern;
015
016import ch.qos.logback.classic.spi.ILoggingEvent;
017
018public class RelativeTimeConverter extends ClassicConverter {
019
020    long lastTimestamp = -1;
021    String timesmapCache = null;
022
023    public String convert(ILoggingEvent event) {
024        long now = event.getTimeStamp();
025
026        synchronized (this) {
027            // update timesmapStrCache only if now != lastTimestamp
028            if (now != lastTimestamp) {
029                lastTimestamp = now;
030                timesmapCache = Long.toString(now - event.getLoggerContextVO().getBirthTime());
031            }
032            return timesmapCache;
033        }
034    }
035}