ErrorManager.java revision 2ad60cfc28e14ee8f0bb038720836a4696c478ad 
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
18package java.util.logging;
19
20import org.apache.harmony.logging.internal.nls.Messages;
21
22/**
23 * <p>
24 * An error reporting facility for {@link Handler} implementations to record any
25 * error that may happen during logging. <code>Handlers</code> should report
26 * errors to an <code>ErrorManager</code>, instead of throwing exceptions,
27 * which would interfere with the log issuer's execution.
28 * </p>
29 */
30public class ErrorManager {
31
32    /**
33     * The error code indicating a failure that does not fit in any of the
34     * specific types of failures that follow.
35     */
36    public static final int GENERIC_FAILURE = 0;
37
38    /**
39     * The error code indicating a failure when writing to an output stream.
40     */
41    public static final int WRITE_FAILURE = 1;
42
43    /**
44     * The error code indicating a failure when flushing an output stream.
45     */
46    public static final int FLUSH_FAILURE = 2;
47
48    /**
49     * The error code indicating a failure when closing an output stream.
50     */
51    public static final int CLOSE_FAILURE = 3;
52
53    /**
54     * The error code indicating a failure when opening an output stream.
55     */
56    public static final int OPEN_FAILURE = 4;
57
58    /**
59     * The error code indicating a failure when formatting the error messages.
60     */
61    public static final int FORMAT_FAILURE = 5;
62
63    @SuppressWarnings("nls")
64    private static final String[] FAILURES = new String[] { "GENERIC_FAILURE",
65            "WRITE_FAILURE", "FLUSH_FAILURE", "CLOSE_FAILURE", "OPEN_FAILURE",
66            "FORMAT_FAILURE" };
67
68    /**
69     * An indicator for determining if the error manager has been called at
70     * least once before.
71     */
72    private boolean called;
73
74    /**
75     * Constructs an instance of <code>ErrorManager</code>.
76     */
77    public ErrorManager() {
78        super();
79    }
80
81    /**
82     * <p>
83     * Reports an error using the given message, exception and error code. This
84     * implementation will write out the message to {@link System#err} on the
85     * first call and all subsequent calls are ignored. A subclass of this class
86     * should override this method.
87     * </p>
88     *
89     * @param message
90     *            The error message, which may be <code>null</code>.
91     * @param exception
92     *            The exception associated with the error, which may be
93     *            <code>null</code>.
94     * @param errorCode
95     *            The error code that identifies the type of error; see the
96     *            constant fields on this class.
97     */
98    public void error(String message, Exception exception, int errorCode) {
99        synchronized (this) {
100            if (called) {
101                return;
102            }
103            called = true;
104        }
105        System.err.println(this.getClass().getName()
106            + ": " + FAILURES[errorCode]); //$NON-NLS-1$
107        if (message != null) {
108            // logging.1E=Error message - {0}
109            System.err.println(Messages.getString("logging.1E", message)); //$NON-NLS-1$
110        }
111        if (exception != null) {
112            // logging.1F=Exception - {0}
113            System.err.println(Messages.getString("logging.1F", exception)); //$NON-NLS-1$
114        }
115    }
116}
117