org.slf4j.ext.MDCStrLookup Maven / Gradle / Ivy
/*
* Copyright (c) 2004-2007 QOS.ch
* All rights reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
package org.slf4j.ext;
import org.apache.commons.lang.text.StrLookup;
import org.slf4j.MDC;
/**
* This class can be used with the Commons Lang StrSubstitutor to replace
* tokens that occur in Strings with their values in the MDC.
*
* @author Ralph Goers
*/
public class MDCStrLookup extends StrLookup {
/**
* Looks up up a value in the MDC.
*
* @param key the key to be looked up, may be null
* @return the matching value, null if no match
*/
public String lookup(String key) {
if (key == null) {
return null;
}
return MDC.get(key);
}
}