ch.qos.logback.classic.pattern.MDCConverter Maven / Gradle / Ivy
/**
* 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 ch.qos.logback.classic.pattern;
import ch.qos.logback.classic.spi.ILoggingEvent;
import java.util.Map;
import static ch.qos.logback.core.util.OptionHelper.extractDefaultReplacement;
public class MDCConverter extends ClassicConverter {
private String key;
private String defaultValue = "";
@Override
public void start() {
String[] keyInfo = extractDefaultReplacement(getFirstOption());
key = keyInfo[0];
if (keyInfo[1] != null) {
defaultValue = keyInfo[1];
}
super.start();
}
@Override
public void stop() {
key = null;
super.stop();
}
@Override
public String convert(ILoggingEvent event) {
Map mdcPropertyMap = event.getMDCPropertyMap();
if (mdcPropertyMap == null) {
return defaultValue;
}
if (key == null) {
return outputMDCForAllKeys(mdcPropertyMap);
} else {
String value = mdcPropertyMap.get(key);
if (value != null) {
return value;
} else {
return defaultValue;
}
}
}
/**
* if no key is specified, return all the values present in the MDC, in the format "k1=v1, k2=v2, ..."
*/
private String outputMDCForAllKeys(Map mdcPropertyMap) {
StringBuilder buf = new StringBuilder();
boolean first = true;
for (Map.Entry entry : mdcPropertyMap.entrySet()) {
if (first) {
first = false;
} else {
buf.append(", ");
}
// format: key0=value0, key1=value1
buf.append(entry.getKey()).append('=').append(entry.getValue());
}
return buf.toString();
}
}