1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package org.apache.log4j.pattern; 19 20 import org.apache.log4j.spi.LoggingEvent; 21 22 23 /** 24 * Return the event's NDC in a StringBuffer. 25 * 26 * @author Ceki Gülcü 27 */ 28 public final class NDCPatternConverter extends LoggingEventPatternConverter { 29 /** 30 * Singleton. 31 */ 32 private static final NDCPatternConverter INSTANCE = 33 new NDCPatternConverter(); 34 35 /** 36 * Private constructor. 37 */ 38 private NDCPatternConverter() { 39 super("NDC", "ndc"); 40 } 41 42 /** 43 * Obtains an instance of NDCPatternConverter. 44 * @param options options, may be null. 45 * @return instance of NDCPatternConverter. 46 */ 47 public static NDCPatternConverter newInstance( 48 final String[] options) { 49 return INSTANCE; 50 } 51 52 /** 53 * {@inheritDoc} 54 */ 55 public void format(final LoggingEvent event, final StringBuffer toAppendTo) { 56 toAppendTo.append(event.getNDC()); 57 } 58 }