1 /*
2 * Copyright 2007-2013 smartics, Kronseder & Reiner GmbH
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package de.smartics.exceptions.i18n;
17
18 import java.io.Serializable;
19 import java.util.ArrayList;
20 import java.util.Collections;
21 import java.util.List;
22 import java.util.Locale;
23
24 import org.apache.commons.lang.StringUtils;
25
26 import de.smartics.exceptions.i18n.message.MessageType;
27 import de.smartics.exceptions.i18n.message.Messages;
28
29 /**
30 * Stores the message information of the causes. The exception whose cause trail
31 * this instance is, is <strong>not</strong> part of the cause trail. This makes
32 * it possible to render all messages without need to skip the first one that is
33 * usually rendered otherwise.
34 */
35 public final class CauseTrailMessages implements Serializable
36 {
37 // ********************************* Fields *********************************
38
39 // --- constants ------------------------------------------------------------
40
41 /**
42 * The class version identifier.
43 */
44 private static final long serialVersionUID = 1L;
45
46 // --- members --------------------------------------------------------------
47
48 /**
49 * The trail of messages to the root.
50 */
51 private final List<Messages> trail = new ArrayList<Messages>();
52
53 // ****************************** Initializer *******************************
54
55 // ****************************** Constructors ******************************
56
57 /**
58 * Convenience constructor using the default locale.
59 *
60 * @param cause the cause to the exception this is the cause trail instance
61 * for.
62 */
63 public CauseTrailMessages(final Throwable cause)
64 {
65 this(Locale.getDefault(), cause);
66 }
67
68 /**
69 * Default constructor.
70 *
71 * @param locale the locale for which the message is requested.
72 * @param cause the cause to the exception this is the cause trail instance
73 * for.
74 */
75 public CauseTrailMessages(final Locale locale, final Throwable cause)
76 {
77 initCauseTrail(locale, cause);
78 }
79
80 // ****************************** Inner Classes *****************************
81
82 // ********************************* Methods ********************************
83
84 // --- init -----------------------------------------------------------------
85
86 private void initCauseTrail(final Locale locale, final Throwable cause)
87 {
88 Throwable current = cause;
89 while (current != null)
90 {
91 if (current instanceof LocalizedException)
92 {
93 final LocalizedException localizedException =
94 (LocalizedException) current;
95 final Messages messages = localizedException.createMessages(locale);
96 trail.add(messages);
97 final CauseTrailMessages causeTrail =
98 localizedException.getCauseTrail(locale);
99 trail.addAll(causeTrail.trail);
100 current = null;
101 }
102 else
103 {
104 final Messages messages = createNonSmarticsExceptionsMessages(current);
105 trail.add(messages);
106 current = current.getCause();
107 }
108 }
109 }
110
111 private Messages createNonSmarticsExceptionsMessages(final Throwable current)
112 {
113 final String text = current.getLocalizedMessage();
114 return new Messages.Builder()
115 .put(MessageType.TITLE, current.getClass().getName())
116 .put(MessageType.SUMMARY, text != null ? text : "n/a").build();
117 }
118
119 // --- get&set --------------------------------------------------------------
120
121 /**
122 * Returns the trail of messages to the root.
123 *
124 * @return the trail of messages to the root.
125 */
126 public List<Messages> getTrail()
127 {
128 return Collections.unmodifiableList(trail);
129 }
130
131 // --- business -------------------------------------------------------------
132
133 // --- object basics --------------------------------------------------------
134
135 @Override
136 public String toString()
137 {
138 final StringBuilder buffer = new StringBuilder(trail.size() * 256);
139
140 int i = 0;
141 for (final Messages messages : trail)
142 {
143 final String prefix = StringUtils.repeat(" ", i++);
144
145 for (final MessageType type : MessageType.values())
146 {
147 final String message = messages.getMessage(type);
148 if (message != null)
149 {
150 buffer.append(prefix).append(type).append('=').append(message)
151 .append('\n');
152 }
153 }
154 }
155
156 return StringUtils.chomp(buffer.toString());
157 }
158 }