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Tomcat85 Slf4j Logback Integration
/**
* Logback: the reliable, generic, fast and flexible logging framework.
* Copyright (C) 1999-2015, QOS.ch. All rights reserved.
*
* This program and the accompanying materials are dual-licensed under
* either the terms of the Eclipse Public License v1.0 as published by
* the Eclipse Foundation
*
* or (per the licensee's choosing)
*
* under the terms of the GNU Lesser General Public License version 2.1
* as published by the Free Software Foundation.
*/
package org.apache.juli.logging.ch.qos.logback.core.util;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;
/**
* A synchronized implementation of SimpleDateFormat which uses caching internally.
*
* @author Ceki Gülcü
* @since 0.9.29
*/
public class CachingDateFormatter {
long lastTimestamp = -1;
String cachedStr = null;
final SimpleDateFormat sdf;
public CachingDateFormatter(String pattern) {
sdf = new SimpleDateFormat(pattern);
}
public final String format(long now) {
// SimpleDateFormat is not thread safe.
// See also the discussion in http://jira.qos.ch/browse/LBCLASSIC-36
// DateFormattingThreadedThroughputCalculator and SelectiveDateFormattingRunnable
// are also noteworthy
// The now == lastTimestamp guard minimizes synchronization
synchronized (this) {
if (now != lastTimestamp) {
lastTimestamp = now;
cachedStr = sdf.format(new Date(now));
}
return cachedStr;
}
}
public void setTimeZone(TimeZone tz) {
sdf.setTimeZone(tz);
}
}