1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.mina.util;
21
22
23
24 /**
25 * Monitors uncaught exceptions. {@link #exceptionCaught(Throwable)} is
26 * invoked when there are any uncaught exceptions.
27 * <p>
28 * You can monitor any uncaught exceptions by setting {@link ExceptionMonitor}
29 * by calling {@link #setInstance(ExceptionMonitor)}. The default
30 * monitor logs all caught exceptions in <tt>WARN</tt> level using
31 * SLF4J.
32 *
33 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
34 *
35 * @see DefaultExceptionMonitor
36 */
37 public abstract class ExceptionMonitor {
38 private static ExceptionMonitor instance = new DefaultExceptionMonitor();
39
40 /**
41 * Returns the current exception monitor.
42 */
43 public static ExceptionMonitor getInstance() {
44 return instance;
45 }
46
47 /**
48 * Sets the uncaught exception monitor. If <code>null</code> is specified,
49 * the default monitor will be set.
50 *
51 * @param monitor A new instance of {@link DefaultExceptionMonitor} is set
52 * if <tt>null</tt> is specified.
53 */
54 public static void setInstance(ExceptionMonitor monitor) {
55 if (monitor == null) {
56 monitor = new DefaultExceptionMonitor();
57 }
58 instance = monitor;
59 }
60
61 /**
62 * Invoked when there are any uncaught exceptions.
63 */
64 public abstract void exceptionCaught(Throwable cause);
65 }