001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache license, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the license for the specific language governing permissions and
015 * limitations under the license.
016 */
017package org.apache.logging.log4j.core.pattern;
018
019import org.apache.logging.log4j.core.LogEvent;
020import org.apache.logging.log4j.core.config.plugins.Plugin;
021import org.apache.logging.log4j.core.impl.LocationAware;
022
023/**
024 * Returns the event's line location information in a StringBuilder.
025 */
026@Plugin(name = "LineLocationPatternConverter", category = PatternConverter.CATEGORY)
027@ConverterKeys({ "L", "line" })
028public final class LineLocationPatternConverter extends LogEventPatternConverter implements LocationAware {
029    /**
030     * Singleton.
031     */
032    private static final LineLocationPatternConverter INSTANCE =
033        new LineLocationPatternConverter();
034
035    /**
036     * Private constructor.
037     */
038    private LineLocationPatternConverter() {
039        super("Line", "line");
040    }
041
042    /**
043     * Obtains an instance of pattern converter.
044     *
045     * @param options options, may be null.
046     * @return instance of pattern converter.
047     */
048    public static LineLocationPatternConverter newInstance(
049        final String[] options) {
050        return INSTANCE;
051    }
052
053    /**
054     * {@inheritDoc}
055     */
056    @Override
057    public void format(final LogEvent event, final StringBuilder output) {
058        final StackTraceElement element = event.getSource();
059
060        if (element != null) {
061            output.append(element.getLineNumber());
062        }
063    }
064
065    @Override
066    public boolean requiresLocation() {
067        return true;
068    }
069}