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 }