1 |
769 |
jeremybenn |
/* EventFilter.java --
|
2 |
|
|
Copyright (C) 1999,2000,2001 Free Software Foundation, Inc.
|
3 |
|
|
|
4 |
|
|
This file is part of GNU Classpath.
|
5 |
|
|
|
6 |
|
|
GNU Classpath is free software; you can redistribute it and/or modify
|
7 |
|
|
it under the terms of the GNU General Public License as published by
|
8 |
|
|
the Free Software Foundation; either version 2, or (at your option)
|
9 |
|
|
any later version.
|
10 |
|
|
|
11 |
|
|
GNU Classpath is distributed in the hope that it will be useful, but
|
12 |
|
|
WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 |
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 |
|
|
General Public License for more details.
|
15 |
|
|
|
16 |
|
|
You should have received a copy of the GNU General Public License
|
17 |
|
|
along with GNU Classpath; see the file COPYING. If not, write to the
|
18 |
|
|
Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
19 |
|
|
02110-1301 USA.
|
20 |
|
|
|
21 |
|
|
Linking this library statically or dynamically with other modules is
|
22 |
|
|
making a combined work based on this library. Thus, the terms and
|
23 |
|
|
conditions of the GNU General Public License cover the whole
|
24 |
|
|
combination.
|
25 |
|
|
|
26 |
|
|
As a special exception, the copyright holders of this library give you
|
27 |
|
|
permission to link this library with independent modules to produce an
|
28 |
|
|
executable, regardless of the license terms of these independent
|
29 |
|
|
modules, and to copy and distribute the resulting executable under
|
30 |
|
|
terms of your choice, provided that you also meet, for each linked
|
31 |
|
|
independent module, the terms and conditions of the license of that
|
32 |
|
|
module. An independent module is a module which is not derived from
|
33 |
|
|
or based on this library. If you modify this library, you may extend
|
34 |
|
|
this exception to your version of the library, but you are not
|
35 |
|
|
obligated to do so. If you do not wish to do so, delete this
|
36 |
|
|
exception statement from your version. */
|
37 |
|
|
|
38 |
|
|
package gnu.xml.pipeline;
|
39 |
|
|
|
40 |
|
|
import java.lang.reflect.InvocationTargetException;
|
41 |
|
|
import java.lang.reflect.Method;
|
42 |
|
|
|
43 |
|
|
import org.xml.sax.*;
|
44 |
|
|
import org.xml.sax.ext.*;
|
45 |
|
|
import org.xml.sax.helpers.XMLFilterImpl;
|
46 |
|
|
|
47 |
|
|
/**
|
48 |
|
|
* A customizable event consumer, used to assemble various kinds of filters
|
49 |
|
|
* using SAX handlers and an optional second consumer. It can be constructed
|
50 |
|
|
* in two ways: <ul>
|
51 |
|
|
*
|
52 |
|
|
* <li> To serve as a passthrough, sending all events to a second consumer.
|
53 |
|
|
* The second consumer may be identified through {@link #getNext}.
|
54 |
|
|
*
|
55 |
|
|
* <li> To serve as a dead end, with all handlers null;
|
56 |
|
|
* {@link #getNext} returns null.
|
57 |
|
|
*
|
58 |
|
|
* </ul>
|
59 |
|
|
*
|
60 |
|
|
* <p> Additionally, SAX handlers may be assigned, which completely replace
|
61 |
|
|
* the "upstream" view (through {@link EventConsumer}) of handlers, initially
|
62 |
|
|
* null or the "next" consumer provided to the constructor. To make
|
63 |
|
|
* it easier to build specialized filter classes, this class implements
|
64 |
|
|
* all the standard SAX consumer handlers, and those implementations
|
65 |
|
|
* delegate "downstream" to the consumer accessed by {@link #getNext}.
|
66 |
|
|
*
|
67 |
|
|
* <p> The simplest way to create a custom a filter class is to create a
|
68 |
|
|
* subclass which overrides one or more handler interface methods. The
|
69 |
|
|
* constructor for that subclass then registers itself as a handler for
|
70 |
|
|
* those interfaces using a call such as <em>setContentHandler(this)</em>,
|
71 |
|
|
* so the "upstream" view of event delivery is modified from the state
|
72 |
|
|
* established in the base class constructor. That way,
|
73 |
|
|
* the overridden methods intercept those event callbacks
|
74 |
|
|
* as they go "downstream", and
|
75 |
|
|
* all other event callbacks will pass events to any next consumer.
|
76 |
|
|
* Overridden methods may invoke superclass methods (perhaps after modifying
|
77 |
|
|
* parameters) if they wish to delegate such calls. Such subclasses
|
78 |
|
|
* should use {@link #getErrorHandler} to report errors using the
|
79 |
|
|
* common error reporting mechanism.
|
80 |
|
|
*
|
81 |
|
|
* <p> Another important technique is to construct a filter consisting
|
82 |
|
|
* of only a few specific types of handler. For example, one could easily
|
83 |
|
|
* prune out lexical events or various declarations by providing handlers
|
84 |
|
|
* which don't pass those events downstream, or by providing null handlers.
|
85 |
|
|
*
|
86 |
|
|
* <hr />
|
87 |
|
|
*
|
88 |
|
|
* <p> This may be viewed as the consumer oriented analogue of the SAX2
|
89 |
|
|
* {@link org.xml.sax.helpers.XMLFilterImpl XMLFilterImpl} class.
|
90 |
|
|
* Key differences include: <ul>
|
91 |
|
|
*
|
92 |
|
|
* <li> This fully separates consumer and producer roles: it
|
93 |
|
|
* does not implement the producer side <em>XMLReader</em> or
|
94 |
|
|
* <em>EntityResolver</em> interfaces, so it can only be used
|
95 |
|
|
* in "push" mode (it has no <em>parse()</em> methods).
|
96 |
|
|
*
|
97 |
|
|
* <li> "Extension" handlers are fully supported, enabling a
|
98 |
|
|
* richer set of application requirements.
|
99 |
|
|
* And it implements {@link EventConsumer}, which groups related
|
100 |
|
|
* consumer methods together, rather than leaving them separated.
|
101 |
|
|
*
|
102 |
|
|
* <li> The chaining which is visible is "downstream" to the next
|
103 |
|
|
* consumer, not "upstream" to the preceding producer.
|
104 |
|
|
* It supports "fan-in", where
|
105 |
|
|
* a consumer can be fed by several producers. (For "fan-out",
|
106 |
|
|
* see the {@link TeeConsumer} class.)
|
107 |
|
|
*
|
108 |
|
|
* <li> Event chaining is set up differently. It is intended to
|
109 |
|
|
* work "upstream" from terminus towards producer, during filter
|
110 |
|
|
* construction, as described above.
|
111 |
|
|
* This is part of an early binding model:
|
112 |
|
|
* events don't need to pass through stages which ignore them.
|
113 |
|
|
*
|
114 |
|
|
* <li> ErrorHandler support is separated, on the grounds that
|
115 |
|
|
* pipeline stages need to share the same error handling policy.
|
116 |
|
|
* For the same reason, error handler setup goes "downstream":
|
117 |
|
|
* when error handlers get set, they are passed to subsequent
|
118 |
|
|
* consumers.
|
119 |
|
|
*
|
120 |
|
|
* </ul>
|
121 |
|
|
*
|
122 |
|
|
* <p> The {@link #chainTo chainTo()} convenience routine supports chaining to
|
123 |
|
|
* an XMLFilterImpl, in its role as a limited functionality event
|
124 |
|
|
* consumer. Its event producer role ({@link XMLFilter}) is ignored.
|
125 |
|
|
*
|
126 |
|
|
* <hr />
|
127 |
|
|
*
|
128 |
|
|
* <p> The {@link #bind bind()} routine may be used associate event pipelines
|
129 |
|
|
* with any kind of {@link XMLReader} that will produce the events.
|
130 |
|
|
* Such pipelines don't necessarily need to have any members which are
|
131 |
|
|
* implemented using this class. That routine has some intelligence
|
132 |
|
|
* which supports automatic changes to parser feature flags, letting
|
133 |
|
|
* event piplines become largely independent of the particular feature
|
134 |
|
|
* sets of parsers.
|
135 |
|
|
*
|
136 |
|
|
* @author David Brownell
|
137 |
|
|
*/
|
138 |
|
|
public class EventFilter
|
139 |
|
|
implements EventConsumer, ContentHandler, DTDHandler,
|
140 |
|
|
LexicalHandler, DeclHandler
|
141 |
|
|
{
|
142 |
|
|
// SAX handlers
|
143 |
|
|
private ContentHandler docHandler, docNext;
|
144 |
|
|
private DTDHandler dtdHandler, dtdNext;
|
145 |
|
|
private LexicalHandler lexHandler, lexNext;
|
146 |
|
|
private DeclHandler declHandler, declNext;
|
147 |
|
|
// and ideally, one more for the stuff SAX2 doesn't show
|
148 |
|
|
|
149 |
|
|
private Locator locator;
|
150 |
|
|
private EventConsumer next;
|
151 |
|
|
private ErrorHandler errHandler;
|
152 |
|
|
|
153 |
|
|
|
154 |
|
|
/** SAX2 URI prefix for standard feature flags. */
|
155 |
|
|
public static final String FEATURE_URI
|
156 |
|
|
= "http://xml.org/sax/features/";
|
157 |
|
|
/** SAX2 URI prefix for standard properties (mostly for handlers). */
|
158 |
|
|
public static final String PROPERTY_URI
|
159 |
|
|
= "http://xml.org/sax/properties/";
|
160 |
|
|
|
161 |
|
|
/** SAX2 property identifier for {@link DeclHandler} events */
|
162 |
|
|
public static final String DECL_HANDLER
|
163 |
|
|
= PROPERTY_URI + "declaration-handler";
|
164 |
|
|
/** SAX2 property identifier for {@link LexicalHandler} events */
|
165 |
|
|
public static final String LEXICAL_HANDLER
|
166 |
|
|
= PROPERTY_URI + "lexical-handler";
|
167 |
|
|
|
168 |
|
|
//
|
169 |
|
|
// These class objects will be null if the relevant class isn't linked.
|
170 |
|
|
// Small configurations (pJava and some kinds of embedded systems) need
|
171 |
|
|
// to facilitate smaller executables. So "instanceof" is undesirable
|
172 |
|
|
// when bind() sees if it can remove some stages.
|
173 |
|
|
//
|
174 |
|
|
// SECURITY NOTE: assuming all these classes are part of the same sealed
|
175 |
|
|
// package, there's no problem saving these in the instance of this class
|
176 |
|
|
// that's associated with "this" class loader. But that wouldn't be true
|
177 |
|
|
// for classes in another package.
|
178 |
|
|
//
|
179 |
|
|
private static boolean loaded;
|
180 |
|
|
private static Class nsClass;
|
181 |
|
|
private static Class validClass;
|
182 |
|
|
private static Class wfClass;
|
183 |
|
|
private static Class xincClass;
|
184 |
|
|
|
185 |
|
|
static ClassLoader getClassLoader ()
|
186 |
|
|
{
|
187 |
|
|
Method m = null;
|
188 |
|
|
|
189 |
|
|
try {
|
190 |
|
|
m = Thread.class.getMethod("getContextClassLoader");
|
191 |
|
|
} catch (NoSuchMethodException e) {
|
192 |
|
|
// Assume that we are running JDK 1.1, use the current ClassLoader
|
193 |
|
|
return EventFilter.class.getClassLoader();
|
194 |
|
|
}
|
195 |
|
|
|
196 |
|
|
try {
|
197 |
|
|
return (ClassLoader) m.invoke(Thread.currentThread());
|
198 |
|
|
} catch (IllegalAccessException e) {
|
199 |
|
|
// assert(false)
|
200 |
|
|
throw new UnknownError(e.getMessage());
|
201 |
|
|
} catch (InvocationTargetException e) {
|
202 |
|
|
// assert(e.getTargetException() instanceof SecurityException)
|
203 |
|
|
throw new UnknownError(e.getMessage());
|
204 |
|
|
}
|
205 |
|
|
}
|
206 |
|
|
|
207 |
|
|
static Class loadClass (ClassLoader classLoader, String className)
|
208 |
|
|
{
|
209 |
|
|
try {
|
210 |
|
|
if (classLoader == null)
|
211 |
|
|
return Class.forName(className);
|
212 |
|
|
else
|
213 |
|
|
return classLoader.loadClass(className);
|
214 |
|
|
} catch (Exception e) {
|
215 |
|
|
return null;
|
216 |
|
|
}
|
217 |
|
|
}
|
218 |
|
|
|
219 |
|
|
static private void loadClasses ()
|
220 |
|
|
{
|
221 |
|
|
ClassLoader loader = getClassLoader ();
|
222 |
|
|
|
223 |
|
|
nsClass = loadClass (loader, "gnu.xml.pipeline.NSFilter");
|
224 |
|
|
validClass = loadClass (loader, "gnu.xml.pipeline.ValidationConsumer");
|
225 |
|
|
wfClass = loadClass (loader, "gnu.xml.pipeline.WellFormednessFilter");
|
226 |
|
|
xincClass = loadClass (loader, "gnu.xml.pipeline.XIncludeFilter");
|
227 |
|
|
loaded = true;
|
228 |
|
|
}
|
229 |
|
|
|
230 |
|
|
|
231 |
|
|
/**
|
232 |
|
|
* Binds the standard SAX2 handlers from the specified consumer
|
233 |
|
|
* pipeline to the specified producer. These handlers include the core
|
234 |
|
|
* {@link ContentHandler} and {@link DTDHandler}, plus the extension
|
235 |
|
|
* {@link DeclHandler} and {@link LexicalHandler}. Any additional
|
236 |
|
|
* application-specific handlers need to be bound separately.
|
237 |
|
|
* The {@link ErrorHandler} is handled differently: the producer's
|
238 |
|
|
* error handler is passed through to the consumer pipeline.
|
239 |
|
|
* The producer is told to include namespace prefix information if it
|
240 |
|
|
* can, since many pipeline stages need that Infoset information to
|
241 |
|
|
* work well.
|
242 |
|
|
*
|
243 |
|
|
* <p> At the head of the pipeline, certain standard event filters are
|
244 |
|
|
* recognized and handled specially. This facilitates construction
|
245 |
|
|
* of processing pipelines that work regardless of the capabilities
|
246 |
|
|
* of the XMLReader implementation in use; for example, it permits
|
247 |
|
|
* validating output of a {@link gnu.xml.util.DomParser}. <ul>
|
248 |
|
|
*
|
249 |
|
|
* <li> {@link NSFilter} will be removed if the producer can be
|
250 |
|
|
* told not to discard namespace data, using the "namespace-prefixes"
|
251 |
|
|
* feature flag.
|
252 |
|
|
*
|
253 |
|
|
* <li> {@link ValidationConsumer} will be removed if the producer
|
254 |
|
|
* can be told to validate, using the "validation" feature flag.
|
255 |
|
|
*
|
256 |
|
|
* <li> {@link WellFormednessFilter} is always removed, on the
|
257 |
|
|
* grounds that no XMLReader is permitted to producee malformed
|
258 |
|
|
* event streams and this would just be processing overhead.
|
259 |
|
|
*
|
260 |
|
|
* <li> {@link XIncludeFilter} stops the special handling, except
|
261 |
|
|
* that it's told about the "namespace-prefixes" feature of the
|
262 |
|
|
* event producer so that the event stream is internally consistent.
|
263 |
|
|
*
|
264 |
|
|
* <li> The first consumer which is not one of those classes stops
|
265 |
|
|
* such special handling. This means that if you want to force
|
266 |
|
|
* one of those filters to be used, you could just precede it with
|
267 |
|
|
* an instance of {@link EventFilter} configured as a pass-through.
|
268 |
|
|
* You might need to do that if you are using an {@link NSFilter}
|
269 |
|
|
* subclass to fix names found in attributes or character data.
|
270 |
|
|
*
|
271 |
|
|
* </ul>
|
272 |
|
|
*
|
273 |
|
|
* <p> Other than that, this method works with any kind of event consumer,
|
274 |
|
|
* not just event filters. Note that in all cases, the standard handlers
|
275 |
|
|
* are assigned; any previous handler assignments for the handler will
|
276 |
|
|
* be overridden.
|
277 |
|
|
*
|
278 |
|
|
* @param producer will deliver events to the specified consumer
|
279 |
|
|
* @param consumer pipeline supplying event handlers to be associated
|
280 |
|
|
* with the producer (may not be null)
|
281 |
|
|
*/
|
282 |
|
|
public static void bind (XMLReader producer, EventConsumer consumer)
|
283 |
|
|
{
|
284 |
|
|
Class klass = null;
|
285 |
|
|
boolean prefixes;
|
286 |
|
|
|
287 |
|
|
if (!loaded)
|
288 |
|
|
loadClasses ();
|
289 |
|
|
|
290 |
|
|
// DOM building, printing, layered validation, and other
|
291 |
|
|
// things don't work well when prefix info is discarded.
|
292 |
|
|
// Include it by default, whenever possible.
|
293 |
|
|
try {
|
294 |
|
|
producer.setFeature (FEATURE_URI + "namespace-prefixes",
|
295 |
|
|
true);
|
296 |
|
|
prefixes = true;
|
297 |
|
|
} catch (SAXException e) {
|
298 |
|
|
prefixes = false;
|
299 |
|
|
}
|
300 |
|
|
|
301 |
|
|
// NOTE: This loop doesn't use "instanceof", since that
|
302 |
|
|
// would prevent compiling/linking without those classes
|
303 |
|
|
// being present.
|
304 |
|
|
while (consumer != null) {
|
305 |
|
|
klass = consumer.getClass ();
|
306 |
|
|
|
307 |
|
|
// we might have already changed this problematic SAX2 default.
|
308 |
|
|
if (nsClass != null && nsClass.isAssignableFrom (klass)) {
|
309 |
|
|
if (!prefixes)
|
310 |
|
|
break;
|
311 |
|
|
consumer = ((EventFilter)consumer).getNext ();
|
312 |
|
|
|
313 |
|
|
// the parser _might_ do DTD validation by default ...
|
314 |
|
|
// if not, maybe we can change this setting.
|
315 |
|
|
} else if (validClass != null
|
316 |
|
|
&& validClass.isAssignableFrom (klass)) {
|
317 |
|
|
try {
|
318 |
|
|
producer.setFeature (FEATURE_URI + "validation",
|
319 |
|
|
true);
|
320 |
|
|
consumer = ((ValidationConsumer)consumer).getNext ();
|
321 |
|
|
} catch (SAXException e) {
|
322 |
|
|
break;
|
323 |
|
|
}
|
324 |
|
|
|
325 |
|
|
// parsers are required not to have such bugs
|
326 |
|
|
} else if (wfClass != null && wfClass.isAssignableFrom (klass)) {
|
327 |
|
|
consumer = ((WellFormednessFilter)consumer).getNext ();
|
328 |
|
|
|
329 |
|
|
// stop on the first pipeline stage we can't remove
|
330 |
|
|
} else
|
331 |
|
|
break;
|
332 |
|
|
|
333 |
|
|
if (consumer == null)
|
334 |
|
|
klass = null;
|
335 |
|
|
}
|
336 |
|
|
|
337 |
|
|
// the actual setting here doesn't matter as much
|
338 |
|
|
// as that producer and consumer agree
|
339 |
|
|
if (xincClass != null && klass != null
|
340 |
|
|
&& xincClass.isAssignableFrom (klass))
|
341 |
|
|
((XIncludeFilter)consumer).setSavingPrefixes (prefixes);
|
342 |
|
|
|
343 |
|
|
// Some SAX parsers can't handle null handlers -- bleech
|
344 |
|
|
DefaultHandler2 h = new DefaultHandler2 ();
|
345 |
|
|
|
346 |
|
|
if (consumer != null && consumer.getContentHandler () != null)
|
347 |
|
|
producer.setContentHandler (consumer.getContentHandler ());
|
348 |
|
|
else
|
349 |
|
|
producer.setContentHandler (h);
|
350 |
|
|
if (consumer != null && consumer.getDTDHandler () != null)
|
351 |
|
|
producer.setDTDHandler (consumer.getDTDHandler ());
|
352 |
|
|
else
|
353 |
|
|
producer.setDTDHandler (h);
|
354 |
|
|
|
355 |
|
|
try {
|
356 |
|
|
Object dh;
|
357 |
|
|
|
358 |
|
|
if (consumer != null)
|
359 |
|
|
dh = consumer.getProperty (DECL_HANDLER);
|
360 |
|
|
else
|
361 |
|
|
dh = null;
|
362 |
|
|
if (dh == null)
|
363 |
|
|
dh = h;
|
364 |
|
|
producer.setProperty (DECL_HANDLER, dh);
|
365 |
|
|
} catch (Exception e) { /* ignore */ }
|
366 |
|
|
try {
|
367 |
|
|
Object lh;
|
368 |
|
|
|
369 |
|
|
if (consumer != null)
|
370 |
|
|
lh = consumer.getProperty (LEXICAL_HANDLER);
|
371 |
|
|
else
|
372 |
|
|
lh = null;
|
373 |
|
|
if (lh == null)
|
374 |
|
|
lh = h;
|
375 |
|
|
producer.setProperty (LEXICAL_HANDLER, lh);
|
376 |
|
|
} catch (Exception e) { /* ignore */ }
|
377 |
|
|
|
378 |
|
|
// this binding goes the other way around
|
379 |
|
|
if (producer.getErrorHandler () == null)
|
380 |
|
|
producer.setErrorHandler (h);
|
381 |
|
|
if (consumer != null)
|
382 |
|
|
consumer.setErrorHandler (producer.getErrorHandler ());
|
383 |
|
|
}
|
384 |
|
|
|
385 |
|
|
/**
|
386 |
|
|
* Initializes all handlers to null.
|
387 |
|
|
*/
|
388 |
|
|
// constructor used by PipelineFactory
|
389 |
|
|
public EventFilter () { }
|
390 |
|
|
|
391 |
|
|
|
392 |
|
|
/**
|
393 |
|
|
* Handlers that are not otherwise set will default to those from
|
394 |
|
|
* the specified consumer, making it easy to pass events through.
|
395 |
|
|
* If the consumer is null, all handlers are initialzed to null.
|
396 |
|
|
*/
|
397 |
|
|
// constructor used by PipelineFactory
|
398 |
|
|
public EventFilter (EventConsumer consumer)
|
399 |
|
|
{
|
400 |
|
|
if (consumer == null)
|
401 |
|
|
return;
|
402 |
|
|
|
403 |
|
|
next = consumer;
|
404 |
|
|
|
405 |
|
|
// We delegate through the "xxNext" handlers, and
|
406 |
|
|
// report the "xxHandler" ones on our input side.
|
407 |
|
|
|
408 |
|
|
// Normally a subclass would both override handler
|
409 |
|
|
// methods and register itself as the "xxHandler".
|
410 |
|
|
|
411 |
|
|
docHandler = docNext = consumer.getContentHandler ();
|
412 |
|
|
dtdHandler = dtdNext = consumer.getDTDHandler ();
|
413 |
|
|
try {
|
414 |
|
|
declHandler = declNext = (DeclHandler)
|
415 |
|
|
consumer.getProperty (DECL_HANDLER);
|
416 |
|
|
} catch (SAXException e) { /* leave value null */ }
|
417 |
|
|
try {
|
418 |
|
|
lexHandler = lexNext = (LexicalHandler)
|
419 |
|
|
consumer.getProperty (LEXICAL_HANDLER);
|
420 |
|
|
} catch (SAXException e) { /* leave value null */ }
|
421 |
|
|
}
|
422 |
|
|
|
423 |
|
|
/**
|
424 |
|
|
* Treats the XMLFilterImpl as a limited functionality event consumer,
|
425 |
|
|
* by arranging to deliver events to it; this lets such classes be
|
426 |
|
|
* "wrapped" as pipeline stages.
|
427 |
|
|
*
|
428 |
|
|
* <p> <em>Upstream Event Setup:</em>
|
429 |
|
|
* If no handlers have been assigned to this EventFilter, then the
|
430 |
|
|
* handlers from specified XMLFilterImpl are returned from this
|
431 |
|
|
* {@link EventConsumer}: the XMLFilterImpl is just "wrapped".
|
432 |
|
|
* Otherwise the specified handlers will be returned.
|
433 |
|
|
*
|
434 |
|
|
* <p> <em>Downstream Event Setup:</em>
|
435 |
|
|
* Subclasses may chain event delivery to the specified XMLFilterImpl
|
436 |
|
|
* by invoking the appropiate superclass methods,
|
437 |
|
|
* as if their constructor passed a "next" EventConsumer to the
|
438 |
|
|
* constructor for this class.
|
439 |
|
|
* If this EventFilter has an ErrorHandler, it is assigned as
|
440 |
|
|
* the error handler for the XMLFilterImpl, just as would be
|
441 |
|
|
* done for a next stage implementing {@link EventConsumer}.
|
442 |
|
|
*
|
443 |
|
|
* @param next the next downstream component of the pipeline.
|
444 |
|
|
* @exception IllegalStateException if the "next" consumer has
|
445 |
|
|
* already been set through the constructor.
|
446 |
|
|
*/
|
447 |
|
|
public void chainTo (XMLFilterImpl next)
|
448 |
|
|
{
|
449 |
|
|
if (this.next != null)
|
450 |
|
|
throw new IllegalStateException ();
|
451 |
|
|
|
452 |
|
|
docNext = next.getContentHandler ();
|
453 |
|
|
if (docHandler == null)
|
454 |
|
|
docHandler = docNext;
|
455 |
|
|
dtdNext = next.getDTDHandler ();
|
456 |
|
|
if (dtdHandler == null)
|
457 |
|
|
dtdHandler = dtdNext;
|
458 |
|
|
|
459 |
|
|
try {
|
460 |
|
|
declNext = (DeclHandler) next.getProperty (DECL_HANDLER);
|
461 |
|
|
if (declHandler == null)
|
462 |
|
|
declHandler = declNext;
|
463 |
|
|
} catch (SAXException e) { /* leave value null */ }
|
464 |
|
|
try {
|
465 |
|
|
lexNext = (LexicalHandler) next.getProperty (LEXICAL_HANDLER);
|
466 |
|
|
if (lexHandler == null)
|
467 |
|
|
lexHandler = lexNext;
|
468 |
|
|
} catch (SAXException e) { /* leave value null */ }
|
469 |
|
|
|
470 |
|
|
if (errHandler != null)
|
471 |
|
|
next.setErrorHandler (errHandler);
|
472 |
|
|
}
|
473 |
|
|
|
474 |
|
|
/**
|
475 |
|
|
* Records the error handler that should be used by this stage, and
|
476 |
|
|
* passes it "downstream" to any subsequent stage.
|
477 |
|
|
*/
|
478 |
|
|
final public void setErrorHandler (ErrorHandler handler)
|
479 |
|
|
{
|
480 |
|
|
errHandler = handler;
|
481 |
|
|
if (next != null)
|
482 |
|
|
next.setErrorHandler (handler);
|
483 |
|
|
}
|
484 |
|
|
|
485 |
|
|
/**
|
486 |
|
|
* Returns the error handler assigned this filter stage, or null
|
487 |
|
|
* if no such assigment has been made.
|
488 |
|
|
*/
|
489 |
|
|
final public ErrorHandler getErrorHandler ()
|
490 |
|
|
{
|
491 |
|
|
return errHandler;
|
492 |
|
|
}
|
493 |
|
|
|
494 |
|
|
|
495 |
|
|
/**
|
496 |
|
|
* Returns the next event consumer in sequence; or null if there
|
497 |
|
|
* is no such handler.
|
498 |
|
|
*/
|
499 |
|
|
final public EventConsumer getNext ()
|
500 |
|
|
{ return next; }
|
501 |
|
|
|
502 |
|
|
|
503 |
|
|
/**
|
504 |
|
|
* Assigns the content handler to use; a null handler indicates
|
505 |
|
|
* that these events will not be forwarded.
|
506 |
|
|
* This overrides the previous settting for this handler, which was
|
507 |
|
|
* probably pointed to the next consumer by the base class constructor.
|
508 |
|
|
*/
|
509 |
|
|
final public void setContentHandler (ContentHandler h)
|
510 |
|
|
{
|
511 |
|
|
docHandler = h;
|
512 |
|
|
}
|
513 |
|
|
|
514 |
|
|
/** Returns the content handler being used. */
|
515 |
|
|
final public ContentHandler getContentHandler ()
|
516 |
|
|
{
|
517 |
|
|
return docHandler;
|
518 |
|
|
}
|
519 |
|
|
|
520 |
|
|
/**
|
521 |
|
|
* Assigns the DTD handler to use; a null handler indicates
|
522 |
|
|
* that these events will not be forwarded.
|
523 |
|
|
* This overrides the previous settting for this handler, which was
|
524 |
|
|
* probably pointed to the next consumer by the base class constructor.
|
525 |
|
|
*/
|
526 |
|
|
final public void setDTDHandler (DTDHandler h)
|
527 |
|
|
{ dtdHandler = h; }
|
528 |
|
|
|
529 |
|
|
/** Returns the dtd handler being used. */
|
530 |
|
|
final public DTDHandler getDTDHandler ()
|
531 |
|
|
{
|
532 |
|
|
return dtdHandler;
|
533 |
|
|
}
|
534 |
|
|
|
535 |
|
|
/**
|
536 |
|
|
* Stores the property, normally a handler; a null handler indicates
|
537 |
|
|
* that these events will not be forwarded.
|
538 |
|
|
* This overrides the previous handler settting, which was probably
|
539 |
|
|
* pointed to the next consumer by the base class constructor.
|
540 |
|
|
*/
|
541 |
|
|
final public void setProperty (String id, Object o)
|
542 |
|
|
throws SAXNotRecognizedException, SAXNotSupportedException
|
543 |
|
|
{
|
544 |
|
|
try {
|
545 |
|
|
Object value = getProperty (id);
|
546 |
|
|
|
547 |
|
|
if (value == o)
|
548 |
|
|
return;
|
549 |
|
|
if (DECL_HANDLER.equals (id)) {
|
550 |
|
|
declHandler = (DeclHandler) o;
|
551 |
|
|
return;
|
552 |
|
|
}
|
553 |
|
|
if (LEXICAL_HANDLER.equals (id)) {
|
554 |
|
|
lexHandler = (LexicalHandler) o;
|
555 |
|
|
return;
|
556 |
|
|
}
|
557 |
|
|
throw new SAXNotSupportedException (id);
|
558 |
|
|
|
559 |
|
|
} catch (ClassCastException e) {
|
560 |
|
|
throw new SAXNotSupportedException (id);
|
561 |
|
|
}
|
562 |
|
|
}
|
563 |
|
|
|
564 |
|
|
/** Retrieves a property of unknown intent (usually a handler) */
|
565 |
|
|
final public Object getProperty (String id)
|
566 |
|
|
throws SAXNotRecognizedException
|
567 |
|
|
{
|
568 |
|
|
if (DECL_HANDLER.equals (id))
|
569 |
|
|
return declHandler;
|
570 |
|
|
if (LEXICAL_HANDLER.equals (id))
|
571 |
|
|
return lexHandler;
|
572 |
|
|
|
573 |
|
|
throw new SAXNotRecognizedException (id);
|
574 |
|
|
}
|
575 |
|
|
|
576 |
|
|
/**
|
577 |
|
|
* Returns any locator provided to the next consumer, if this class
|
578 |
|
|
* (or a subclass) is handling {@link ContentHandler } events.
|
579 |
|
|
*/
|
580 |
|
|
public Locator getDocumentLocator ()
|
581 |
|
|
{ return locator; }
|
582 |
|
|
|
583 |
|
|
|
584 |
|
|
// CONTENT HANDLER DELEGATIONS
|
585 |
|
|
|
586 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
587 |
|
|
public void setDocumentLocator (Locator locator)
|
588 |
|
|
{
|
589 |
|
|
this.locator = locator;
|
590 |
|
|
if (docNext != null)
|
591 |
|
|
docNext.setDocumentLocator (locator);
|
592 |
|
|
}
|
593 |
|
|
|
594 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
595 |
|
|
public void startDocument () throws SAXException
|
596 |
|
|
{
|
597 |
|
|
if (docNext != null)
|
598 |
|
|
docNext.startDocument ();
|
599 |
|
|
}
|
600 |
|
|
|
601 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
602 |
|
|
public void skippedEntity (String name) throws SAXException
|
603 |
|
|
{
|
604 |
|
|
if (docNext != null)
|
605 |
|
|
docNext.skippedEntity (name);
|
606 |
|
|
}
|
607 |
|
|
|
608 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
609 |
|
|
public void processingInstruction (String target, String data)
|
610 |
|
|
throws SAXException
|
611 |
|
|
{
|
612 |
|
|
if (docNext != null)
|
613 |
|
|
docNext.processingInstruction (target, data);
|
614 |
|
|
}
|
615 |
|
|
|
616 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
617 |
|
|
public void characters (char ch [], int start, int length)
|
618 |
|
|
throws SAXException
|
619 |
|
|
{
|
620 |
|
|
if (docNext != null)
|
621 |
|
|
docNext.characters (ch, start, length);
|
622 |
|
|
}
|
623 |
|
|
|
624 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
625 |
|
|
public void ignorableWhitespace (char ch [], int start, int length)
|
626 |
|
|
throws SAXException
|
627 |
|
|
{
|
628 |
|
|
if (docNext != null)
|
629 |
|
|
docNext.ignorableWhitespace (ch, start, length);
|
630 |
|
|
}
|
631 |
|
|
|
632 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
633 |
|
|
public void startPrefixMapping (String prefix, String uri)
|
634 |
|
|
throws SAXException
|
635 |
|
|
{
|
636 |
|
|
if (docNext != null)
|
637 |
|
|
docNext.startPrefixMapping (prefix, uri);
|
638 |
|
|
}
|
639 |
|
|
|
640 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
641 |
|
|
public void startElement (
|
642 |
|
|
String uri, String localName,
|
643 |
|
|
String qName, Attributes atts
|
644 |
|
|
) throws SAXException
|
645 |
|
|
{
|
646 |
|
|
if (docNext != null)
|
647 |
|
|
docNext.startElement (uri, localName, qName, atts);
|
648 |
|
|
}
|
649 |
|
|
|
650 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
651 |
|
|
public void endElement (String uri, String localName, String qName)
|
652 |
|
|
throws SAXException
|
653 |
|
|
{
|
654 |
|
|
if (docNext != null)
|
655 |
|
|
docNext.endElement (uri, localName, qName);
|
656 |
|
|
}
|
657 |
|
|
|
658 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
659 |
|
|
public void endPrefixMapping (String prefix) throws SAXException
|
660 |
|
|
{
|
661 |
|
|
if (docNext != null)
|
662 |
|
|
docNext.endPrefixMapping (prefix);
|
663 |
|
|
}
|
664 |
|
|
|
665 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
666 |
|
|
public void endDocument () throws SAXException
|
667 |
|
|
{
|
668 |
|
|
if (docNext != null)
|
669 |
|
|
docNext.endDocument ();
|
670 |
|
|
locator = null;
|
671 |
|
|
}
|
672 |
|
|
|
673 |
|
|
|
674 |
|
|
// DTD HANDLER DELEGATIONS
|
675 |
|
|
|
676 |
|
|
/** <b>SAX1:</b> passes this callback to the next consumer, if any */
|
677 |
|
|
public void unparsedEntityDecl (
|
678 |
|
|
String name,
|
679 |
|
|
String publicId,
|
680 |
|
|
String systemId,
|
681 |
|
|
String notationName
|
682 |
|
|
) throws SAXException
|
683 |
|
|
{
|
684 |
|
|
if (dtdNext != null)
|
685 |
|
|
dtdNext.unparsedEntityDecl (name, publicId, systemId, notationName);
|
686 |
|
|
}
|
687 |
|
|
|
688 |
|
|
/** <b>SAX1:</b> passes this callback to the next consumer, if any */
|
689 |
|
|
public void notationDecl (String name, String publicId, String systemId)
|
690 |
|
|
throws SAXException
|
691 |
|
|
{
|
692 |
|
|
if (dtdNext != null)
|
693 |
|
|
dtdNext.notationDecl (name, publicId, systemId);
|
694 |
|
|
}
|
695 |
|
|
|
696 |
|
|
|
697 |
|
|
// LEXICAL HANDLER DELEGATIONS
|
698 |
|
|
|
699 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
700 |
|
|
public void startDTD (String name, String publicId, String systemId)
|
701 |
|
|
throws SAXException
|
702 |
|
|
{
|
703 |
|
|
if (lexNext != null)
|
704 |
|
|
lexNext.startDTD (name, publicId, systemId);
|
705 |
|
|
}
|
706 |
|
|
|
707 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
708 |
|
|
public void endDTD ()
|
709 |
|
|
throws SAXException
|
710 |
|
|
{
|
711 |
|
|
if (lexNext != null)
|
712 |
|
|
lexNext.endDTD ();
|
713 |
|
|
}
|
714 |
|
|
|
715 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
716 |
|
|
public void comment (char ch [], int start, int length)
|
717 |
|
|
throws SAXException
|
718 |
|
|
{
|
719 |
|
|
if (lexNext != null)
|
720 |
|
|
lexNext.comment (ch, start, length);
|
721 |
|
|
}
|
722 |
|
|
|
723 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
724 |
|
|
public void startCDATA ()
|
725 |
|
|
throws SAXException
|
726 |
|
|
{
|
727 |
|
|
if (lexNext != null)
|
728 |
|
|
lexNext.startCDATA ();
|
729 |
|
|
}
|
730 |
|
|
|
731 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
732 |
|
|
public void endCDATA ()
|
733 |
|
|
throws SAXException
|
734 |
|
|
{
|
735 |
|
|
if (lexNext != null)
|
736 |
|
|
lexNext.endCDATA ();
|
737 |
|
|
}
|
738 |
|
|
|
739 |
|
|
/**
|
740 |
|
|
* <b>SAX2:</b> passes this callback to the next consumer, if any.
|
741 |
|
|
*/
|
742 |
|
|
public void startEntity (String name)
|
743 |
|
|
throws SAXException
|
744 |
|
|
{
|
745 |
|
|
if (lexNext != null)
|
746 |
|
|
lexNext.startEntity (name);
|
747 |
|
|
}
|
748 |
|
|
|
749 |
|
|
/**
|
750 |
|
|
* <b>SAX2:</b> passes this callback to the next consumer, if any.
|
751 |
|
|
*/
|
752 |
|
|
public void endEntity (String name)
|
753 |
|
|
throws SAXException
|
754 |
|
|
{
|
755 |
|
|
if (lexNext != null)
|
756 |
|
|
lexNext.endEntity (name);
|
757 |
|
|
}
|
758 |
|
|
|
759 |
|
|
|
760 |
|
|
// DECLARATION HANDLER DELEGATIONS
|
761 |
|
|
|
762 |
|
|
|
763 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
764 |
|
|
public void elementDecl (String name, String model)
|
765 |
|
|
throws SAXException
|
766 |
|
|
{
|
767 |
|
|
if (declNext != null)
|
768 |
|
|
declNext.elementDecl (name, model);
|
769 |
|
|
}
|
770 |
|
|
|
771 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
772 |
|
|
public void attributeDecl (String eName, String aName,
|
773 |
|
|
String type, String mode, String value)
|
774 |
|
|
throws SAXException
|
775 |
|
|
{
|
776 |
|
|
if (declNext != null)
|
777 |
|
|
declNext.attributeDecl (eName, aName, type, mode, value);
|
778 |
|
|
}
|
779 |
|
|
|
780 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
781 |
|
|
public void externalEntityDecl (String name,
|
782 |
|
|
String publicId, String systemId)
|
783 |
|
|
throws SAXException
|
784 |
|
|
{
|
785 |
|
|
if (declNext != null)
|
786 |
|
|
declNext.externalEntityDecl (name, publicId, systemId);
|
787 |
|
|
}
|
788 |
|
|
|
789 |
|
|
/** <b>SAX2:</b> passes this callback to the next consumer, if any */
|
790 |
|
|
public void internalEntityDecl (String name, String value)
|
791 |
|
|
throws SAXException
|
792 |
|
|
{
|
793 |
|
|
if (declNext != null)
|
794 |
|
|
declNext.internalEntityDecl (name, value);
|
795 |
|
|
}
|
796 |
|
|
}
|