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.varia;
19
20 import org.apache.log4j.AppenderSkeleton;
21 import org.apache.log4j.spi.LoggingEvent;
22
23 /**
24 * A NullAppender merely exists, it never outputs a message to any
25 * device.
26 * @author Ceki Gülc¨
27 */
28 public class NullAppender extends AppenderSkeleton {
29
30 private static NullAppender instance = new NullAppender();
31
32 public NullAppender() {
33 }
34
35 /**
36 * There are no options to acticate.
37 * */
38 public void activateOptions() {
39 }
40
41 /**
42 * Whenever you can, use this method to retreive an instance instead
43 * of instantiating a new one with <code>new</code>.
44 * @deprecated Use getNullAppender instead. getInstance should have been static.
45 * */
46 public NullAppender getInstance() {
47 return instance;
48 }
49
50 /**
51 * Whenever you can, use this method to retreive an instance instead
52 * of instantiating a new one with <code>new</code>.
53 * */
54 public static NullAppender getNullAppender() {
55 return instance;
56 }
57
58 public void close() {
59 }
60
61 /**
62 * Does not do anything.
63 * */
64 public void doAppend(LoggingEvent event) {
65 }
66
67 /**
68 * Does not do anything.
69 * */
70 protected void append(LoggingEvent event) {
71 }
72
73 /**
74 * NullAppenders do not need a layout.
75 * */
76 public boolean requiresLayout() {
77 return false;
78 }
79 }