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.
/**
 * 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 java.util.Map;

import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.classic.spi.LoggerContextVO;

public final class PropertyConverter extends ClassicConverter {

    String key;

    public void start() {
        String optStr = getFirstOption();
        if (optStr != null) {
            key = optStr;
            super.start();
        }
    }

    public String convert(ILoggingEvent event) {
        if (key == null) {
            return "Property_HAS_NO_KEY";
        } else {
            LoggerContextVO lcvo = event.getLoggerContextVO();
            Map<String, String> map = lcvo.getPropertyMap();
            String val = map.get(key);
            if (val != null) {
                return val;
            } else {
                return System.getProperty(key);
            }
        }
    }
}