|
|||||||||||||||||||
30 day Evaluation Version distributed via the Maven Jar Repository. Clover is not free. You have 30 days to evaluate it. Please visit http://www.thecortex.net/clover to obtain a licensed version of Clover | |||||||||||||||||||
Source file | Conditionals | Statements | Methods | TOTAL | |||||||||||||||
ExceptionAnalyzer.java | 87% | 91% | 71.4% | 89.2% |
|
1 |
// Copyright 2004, 2005 The Apache Software Foundation
|
|
2 |
//
|
|
3 |
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
4 |
// you may not use this file except in compliance with the License.
|
|
5 |
// You may obtain a copy of the License at
|
|
6 |
//
|
|
7 |
// http://www.apache.org/licenses/LICENSE-2.0
|
|
8 |
//
|
|
9 |
// Unless required by applicable law or agreed to in writing, software
|
|
10 |
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
11 |
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
12 |
// See the License for the specific language governing permissions and
|
|
13 |
// limitations under the License.
|
|
14 |
|
|
15 |
package org.apache.tapestry.util.exception;
|
|
16 |
|
|
17 |
import java.beans.BeanInfo;
|
|
18 |
import java.beans.IntrospectionException;
|
|
19 |
import java.beans.Introspector;
|
|
20 |
import java.beans.PropertyDescriptor;
|
|
21 |
import java.io.CharArrayWriter;
|
|
22 |
import java.io.IOException;
|
|
23 |
import java.io.LineNumberReader;
|
|
24 |
import java.io.PrintStream;
|
|
25 |
import java.io.PrintWriter;
|
|
26 |
import java.io.StringReader;
|
|
27 |
import java.lang.reflect.Method;
|
|
28 |
import java.util.ArrayList;
|
|
29 |
import java.util.List;
|
|
30 |
|
|
31 |
/**
|
|
32 |
* Analyzes an exception, creating one or more {@link ExceptionDescription}s from it.
|
|
33 |
*
|
|
34 |
* @author Howard Lewis Ship
|
|
35 |
*/
|
|
36 |
|
|
37 |
public class ExceptionAnalyzer |
|
38 |
{ |
|
39 |
private final List exceptionDescriptions = new ArrayList(); |
|
40 |
|
|
41 |
private final List propertyDescriptions = new ArrayList(); |
|
42 |
|
|
43 |
private final CharArrayWriter writer = new CharArrayWriter(); |
|
44 |
|
|
45 |
private boolean exhaustive = false; |
|
46 |
|
|
47 |
/**
|
|
48 |
* If true, then stack trace is extracted for each exception. If false, the default, then stack
|
|
49 |
* trace is extracted for only the deepest exception.
|
|
50 |
*/
|
|
51 |
|
|
52 | 0 |
public boolean isExhaustive() |
53 |
{ |
|
54 | 0 |
return exhaustive;
|
55 |
} |
|
56 |
|
|
57 | 0 |
public void setExhaustive(boolean value) |
58 |
{ |
|
59 | 0 |
exhaustive = value; |
60 |
} |
|
61 |
|
|
62 |
/**
|
|
63 |
* Analyzes the exceptions. This builds an {@link ExceptionDescription}for the exception. It
|
|
64 |
* also looks for a non-null {@link Throwable}property. If one exists, then a second
|
|
65 |
* {@link ExceptionDescription}is created. This continues until no more nested exceptions can
|
|
66 |
* be found.
|
|
67 |
* <p>
|
|
68 |
* The description includes a set of name/value properties (as {@link ExceptionProperty})
|
|
69 |
* object. This list contains all non-null properties that are not, themselves,
|
|
70 |
* {@link Throwable}.
|
|
71 |
* <p>
|
|
72 |
* The name is the display name (not the logical name) of the property. The value is the
|
|
73 |
* <code>toString()</code> value of the property. Only properties defined in subclasses of
|
|
74 |
* {@link Throwable}are included.
|
|
75 |
* <p>
|
|
76 |
* A future enhancement will be to alphabetically sort the properties by name.
|
|
77 |
*/
|
|
78 |
|
|
79 | 28 |
public ExceptionDescription[] analyze(Throwable exception)
|
80 |
{ |
|
81 | 28 |
try
|
82 |
{ |
|
83 |
|
|
84 | 28 |
while (exception != null) |
85 |
{ |
|
86 | 38 |
exception = buildDescription(exception); |
87 |
} |
|
88 |
|
|
89 | 28 |
ExceptionDescription[] result = new ExceptionDescription[exceptionDescriptions.size()];
|
90 |
|
|
91 | 28 |
return (ExceptionDescription[]) exceptionDescriptions.toArray(result);
|
92 |
} |
|
93 |
finally
|
|
94 |
{ |
|
95 | 28 |
exceptionDescriptions.clear(); |
96 | 28 |
propertyDescriptions.clear(); |
97 |
|
|
98 | 28 |
writer.reset(); |
99 |
} |
|
100 |
} |
|
101 |
|
|
102 | 38 |
protected Throwable buildDescription(Throwable exception)
|
103 |
{ |
|
104 | 38 |
BeanInfo info; |
105 | 38 |
Class exceptionClass; |
106 | 38 |
ExceptionProperty property; |
107 | 38 |
PropertyDescriptor[] descriptors; |
108 | 38 |
PropertyDescriptor descriptor; |
109 | 38 |
Throwable next = null;
|
110 | 38 |
int i;
|
111 | 38 |
Object value; |
112 | 38 |
Method method; |
113 | 38 |
ExceptionProperty[] properties; |
114 | 38 |
ExceptionDescription description; |
115 | 38 |
String stringValue; |
116 | 38 |
String message; |
117 | 38 |
String[] stackTrace = null;
|
118 |
|
|
119 | 38 |
propertyDescriptions.clear(); |
120 |
|
|
121 | 38 |
message = exception.getMessage(); |
122 | 38 |
exceptionClass = exception.getClass(); |
123 |
|
|
124 |
// Get properties, ignoring those in Throwable and higher
|
|
125 |
// (including the 'message' property).
|
|
126 |
|
|
127 | 38 |
try
|
128 |
{ |
|
129 | 38 |
info = Introspector.getBeanInfo(exceptionClass, Throwable.class);
|
130 |
} |
|
131 |
catch (IntrospectionException e)
|
|
132 |
{ |
|
133 | 0 |
return null; |
134 |
} |
|
135 |
|
|
136 | 38 |
descriptors = info.getPropertyDescriptors(); |
137 |
|
|
138 | 38 |
for (i = 0; i < descriptors.length; i++)
|
139 |
{ |
|
140 | 135 |
descriptor = descriptors[i]; |
141 |
|
|
142 | 135 |
method = descriptor.getReadMethod(); |
143 | 135 |
if (method == null) |
144 | 0 |
continue;
|
145 |
|
|
146 | 135 |
try
|
147 |
{ |
|
148 | 135 |
value = method.invoke(exception, null);
|
149 |
} |
|
150 |
catch (Exception e)
|
|
151 |
{ |
|
152 | 0 |
continue;
|
153 |
} |
|
154 |
|
|
155 | 135 |
if (value == null) |
156 | 66 |
continue;
|
157 |
|
|
158 |
// Some annoying exceptions duplicate the message property
|
|
159 |
// (I'm talking to YOU SAXParseException), so just edit that out.
|
|
160 |
|
|
161 | 69 |
if (message != null && message.equals(value)) |
162 | 0 |
continue;
|
163 |
|
|
164 |
// Skip Throwables ... but the first non-null
|
|
165 |
// found is the next exception. We kind of count
|
|
166 |
// on there being no more than one Throwable
|
|
167 |
// property per Exception.
|
|
168 |
|
|
169 | 69 |
if (value instanceof Throwable) |
170 |
{ |
|
171 | 18 |
if (next == null) |
172 | 10 |
next = (Throwable) value; |
173 |
|
|
174 | 18 |
continue;
|
175 |
} |
|
176 |
|
|
177 | 51 |
stringValue = value.toString().trim(); |
178 |
|
|
179 | 51 |
if (stringValue.length() == 0)
|
180 | 0 |
continue;
|
181 |
|
|
182 | 51 |
property = new ExceptionProperty(descriptor.getDisplayName(), value);
|
183 |
|
|
184 | 51 |
propertyDescriptions.add(property); |
185 |
} |
|
186 |
|
|
187 |
// If exhaustive, or in the deepest exception (where there's no next)
|
|
188 |
// the extract the stack trace.
|
|
189 |
|
|
190 | 38 |
if (next == null || exhaustive) |
191 | 28 |
stackTrace = getStackTrace(exception); |
192 |
|
|
193 |
// Would be nice to sort the properties here.
|
|
194 |
|
|
195 | 38 |
properties = new ExceptionProperty[propertyDescriptions.size()];
|
196 |
|
|
197 | 38 |
ExceptionProperty[] propArray = (ExceptionProperty[]) propertyDescriptions |
198 |
.toArray(properties); |
|
199 |
|
|
200 | 38 |
description = new ExceptionDescription(exceptionClass.getName(), message, propArray,
|
201 |
stackTrace); |
|
202 |
|
|
203 | 38 |
exceptionDescriptions.add(description); |
204 |
|
|
205 | 38 |
return next;
|
206 |
} |
|
207 |
|
|
208 |
/**
|
|
209 |
* Gets the stack trace for the exception, and converts it into an array of strings.
|
|
210 |
* <p>
|
|
211 |
* This involves parsing the string generated indirectly from
|
|
212 |
* <code>Throwable.printStackTrace(PrintWriter)</code>. This method can get confused if the
|
|
213 |
* message (presumably, the first line emitted by printStackTrace()) spans multiple lines.
|
|
214 |
* <p>
|
|
215 |
* Different JVMs format the exception in different ways.
|
|
216 |
* <p>
|
|
217 |
* A possible expansion would be more flexibility in defining the pattern used. Hopefully all
|
|
218 |
* 'mainstream' JVMs are close enough for this to continue working.
|
|
219 |
*/
|
|
220 |
|
|
221 | 28 |
protected String[] getStackTrace(Throwable exception)
|
222 |
{ |
|
223 | 28 |
writer.reset(); |
224 |
|
|
225 | 28 |
PrintWriter printWriter = new PrintWriter(writer);
|
226 |
|
|
227 | 28 |
exception.printStackTrace(printWriter); |
228 |
|
|
229 | 28 |
printWriter.close(); |
230 |
|
|
231 | 28 |
String fullTrace = writer.toString(); |
232 |
|
|
233 | 28 |
writer.reset(); |
234 |
|
|
235 |
// OK, the trick is to convert the full trace into an array of stack frames.
|
|
236 |
|
|
237 | 28 |
StringReader stringReader = new StringReader(fullTrace);
|
238 | 28 |
LineNumberReader lineReader = new LineNumberReader(stringReader);
|
239 | 28 |
int lineNumber = 0;
|
240 | 28 |
List frames = new ArrayList();
|
241 |
|
|
242 | 28 |
try
|
243 |
{ |
|
244 | 28 |
while (true) |
245 |
{ |
|
246 | 1627 |
String line = lineReader.readLine(); |
247 |
|
|
248 | 1627 |
if (line == null) |
249 | 28 |
break;
|
250 |
|
|
251 |
// Always ignore the first line.
|
|
252 |
|
|
253 | 1599 |
if (++lineNumber == 1)
|
254 | 28 |
continue;
|
255 |
|
|
256 | 1571 |
frames.add(stripFrame(line)); |
257 |
} |
|
258 |
|
|
259 | 28 |
lineReader.close(); |
260 |
} |
|
261 |
catch (IOException ex)
|
|
262 |
{ |
|
263 |
// Not likely to happen with this particular set
|
|
264 |
// of readers.
|
|
265 |
} |
|
266 |
|
|
267 | 28 |
String result[] = new String[frames.size()];
|
268 |
|
|
269 | 28 |
return (String[]) frames.toArray(result);
|
270 |
} |
|
271 |
|
|
272 |
private static final int SKIP_LEADING_WHITESPACE = 0; |
|
273 |
|
|
274 |
private static final int SKIP_T = 1; |
|
275 |
|
|
276 |
private static final int SKIP_OTHER_WHITESPACE = 2; |
|
277 |
|
|
278 |
/**
|
|
279 |
* Sun's JVM prefixes each line in the stack trace with " <tab>at ", other JVMs don't. This
|
|
280 |
* method looks for and strips such stuff.
|
|
281 |
*/
|
|
282 |
|
|
283 | 1571 |
private String stripFrame(String frame)
|
284 |
{ |
|
285 | 1571 |
char array[] = frame.toCharArray();
|
286 |
|
|
287 | 1571 |
int i = 0;
|
288 | 1571 |
int state = SKIP_LEADING_WHITESPACE;
|
289 | 1571 |
boolean more = true; |
290 |
|
|
291 | 1571 |
while (more)
|
292 |
{ |
|
293 |
// Ran out of characters to skip? Return the empty string.
|
|
294 |
|
|
295 | 7893 |
if (i == array.length)
|
296 | 1 |
return ""; |
297 |
|
|
298 | 7892 |
char ch = array[i];
|
299 |
|
|
300 | 7892 |
switch (state)
|
301 |
{ |
|
302 |
// Ignore whitespace at the start of the line.
|
|
303 |
|
|
304 |
case SKIP_LEADING_WHITESPACE:
|
|
305 |
|
|
306 | 3197 |
if (Character.isWhitespace(ch))
|
307 |
{ |
|
308 | 1627 |
i++; |
309 | 1627 |
continue;
|
310 |
} |
|
311 |
|
|
312 | 1570 |
if (ch == 'a')
|
313 |
{ |
|
314 | 1565 |
state = SKIP_T; |
315 | 1565 |
i++; |
316 | 1565 |
continue;
|
317 |
} |
|
318 |
|
|
319 |
// Found non-whitespace, not 'a'
|
|
320 | 5 |
more = false;
|
321 | 5 |
break;
|
322 |
|
|
323 |
// Skip over the 't' after an 'a'
|
|
324 |
|
|
325 |
case SKIP_T:
|
|
326 |
|
|
327 | 1565 |
if (ch == 't')
|
328 |
{ |
|
329 | 1565 |
state = SKIP_OTHER_WHITESPACE; |
330 | 1565 |
i++; |
331 | 1565 |
continue;
|
332 |
} |
|
333 |
|
|
334 |
// Back out the skipped-over 'a'
|
|
335 |
|
|
336 | 0 |
i--; |
337 | 0 |
more = false;
|
338 | 0 |
break;
|
339 |
|
|
340 |
// Skip whitespace between 'at' and the name of the class
|
|
341 |
|
|
342 |
case SKIP_OTHER_WHITESPACE:
|
|
343 |
|
|
344 | 3130 |
if (Character.isWhitespace(ch))
|
345 |
{ |
|
346 | 1565 |
i++; |
347 | 1565 |
continue;
|
348 |
} |
|
349 |
|
|
350 |
// Not whitespace
|
|
351 | 1565 |
more = false;
|
352 | 1565 |
break;
|
353 |
} |
|
354 |
|
|
355 |
} |
|
356 |
|
|
357 |
// Found nothing to strip out.
|
|
358 |
|
|
359 | 1570 |
if (i == 0)
|
360 | 1 |
return frame;
|
361 |
|
|
362 | 1569 |
return frame.substring(i);
|
363 |
} |
|
364 |
|
|
365 |
/**
|
|
366 |
* Produces a text based exception report to the provided stream.
|
|
367 |
*/
|
|
368 |
|
|
369 | 3 |
public void reportException(Throwable exception, PrintStream stream) |
370 |
{ |
|
371 | 3 |
int i;
|
372 | 3 |
int j;
|
373 | 3 |
ExceptionDescription[] descriptions; |
374 | 3 |
ExceptionProperty[] properties; |
375 | 3 |
String[] stackTrace; |
376 | 3 |
String message; |
377 |
|
|
378 | 3 |
descriptions = analyze(exception); |
379 |
|
|
380 | 3 |
for (i = 0; i < descriptions.length; i++)
|
381 |
{ |
|
382 | 3 |
message = descriptions[i].getMessage(); |
383 |
|
|
384 | 3 |
if (message == null) |
385 | 0 |
stream.println(descriptions[i].getExceptionClassName()); |
386 |
else
|
|
387 | 3 |
stream.println(descriptions[i].getExceptionClassName() + ": "
|
388 |
+ descriptions[i].getMessage()); |
|
389 |
|
|
390 | 3 |
properties = descriptions[i].getProperties(); |
391 |
|
|
392 | 3 |
for (j = 0; j < properties.length; j++)
|
393 | 6 |
stream.println(" " + properties[j].getName() + ": " + properties[j].getValue()); |
394 |
|
|
395 |
// Just show the stack trace on the deepest exception.
|
|
396 |
|
|
397 | 3 |
if (i + 1 == descriptions.length)
|
398 |
{ |
|
399 | 3 |
stackTrace = descriptions[i].getStackTrace(); |
400 |
|
|
401 | 3 |
for (j = 0; j < stackTrace.length; j++)
|
402 | 157 |
stream.println(stackTrace[j]); |
403 |
} |
|
404 |
else
|
|
405 | 0 |
stream.println(); |
406 |
} |
|
407 |
} |
|
408 |
|
|
409 |
} |
|