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.util.PerformanceSensitive; 022 023 024/** 025 * Returns the event's NDC in a StringBuilder. 026 */ 027@Plugin(name = "NdcPatternConverter", category = PatternConverter.CATEGORY) 028@ConverterKeys({"x", "NDC"}) 029public final class NdcPatternConverter extends LogEventPatternConverter { 030 /** 031 * Singleton. 032 */ 033 private static final NdcPatternConverter INSTANCE = 034 new NdcPatternConverter(); 035 036 /** 037 * Private constructor. 038 */ 039 private NdcPatternConverter() { 040 super("NDC", "ndc"); 041 } 042 043 /** 044 * Obtains an instance of NdcPatternConverter. 045 * 046 * @param options options, may be null. 047 * @return instance of NdcPatternConverter. 048 */ 049 public static NdcPatternConverter newInstance(final String[] options) { 050 return INSTANCE; 051 } 052 053 @Override 054 @PerformanceSensitive("allocation") 055 public void format(final LogEvent event, final StringBuilder toAppendTo) { 056 toAppendTo.append(event.getContextStack()); 057 } 058}