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1
17
18 package javax.servlet.jsp.el;
19
20 import java.beans.FeatureDescriptor  ;
21 import java.util.AbstractMap ;
22 import java.util.ArrayList ;
23 import java.util.Arrays ;
24 import java.util.Enumeration ;
25 import java.util.HashSet ;
26 import java.util.Iterator ;
27 import java.util.List ;
28 import java.util.Map ;
29 import java.util.Set ;
30 import java.util.Vector ;
31
32 import javax.el.ELContext;
33 import javax.el.ELException;
34 import javax.el.ELResolver;
35 import javax.el.PropertyNotFoundException;
36 import javax.el.PropertyNotWritableException;
37 import javax.servlet.http.Cookie ;
38 import javax.servlet.http.HttpServletRequest ;
39 import javax.servlet.http.HttpSession ;
40 import javax.servlet.jsp.JspContext ;
41 import javax.servlet.jsp.PageContext ;
42
43
47 public class ImplicitObjectELResolver extends ELResolver {
48
49 private final static String [] SCOPE_NAMES = new String [] {
50 "applicationScope", "cookie", "header", "headerValues",
51 "initParam", "pageContext", "pageScope", "param", "paramValues",
52 "requestScope", "sessionScope" };
53
54 private final static int APPLICATIONSCOPE = 0;
55
56 private final static int COOKIE = 1;
57
58 private final static int HEADER = 2;
59
60 private final static int HEADERVALUES = 3;
61
62 private final static int INITPARAM = 4;
63
64 private final static int PAGECONTEXT = 5;
65
66 private final static int PAGESCOPE = 6;
67
68 private final static int PARAM = 7;
69
70 private final static int PARAM_VALUES = 8;
71
72 private final static int REQUEST_SCOPE = 9;
73
74 private final static int SESSION_SCOPE = 10;
75
76 public ImplicitObjectELResolver() {
77 super();
78 }
79
80 public Object getValue(ELContext context, Object base, Object property)
81 throws NullPointerException , PropertyNotFoundException, ELException {
82 if (context == null) {
83 throw new NullPointerException ();
84 }
85
86 if (base == null && property != null) {
87 int idx = Arrays.binarySearch(SCOPE_NAMES, property.toString());
88
89 if (idx >= 0) {
90 PageContext page = (PageContext ) context
91 .getContext(JspContext .class);
92 context.setPropertyResolved(true);
93 switch (idx) {
94 case APPLICATIONSCOPE:
95 return ScopeManager.get(page).getApplicationScope();
96 case COOKIE:
97 return ScopeManager.get(page).getCookie();
98 case HEADER:
99 return ScopeManager.get(page).getHeader();
100 case HEADERVALUES:
101 return ScopeManager.get(page).getHeaderValues();
102 case INITPARAM:
103 return ScopeManager.get(page).getInitParam();
104 case PAGECONTEXT:
105 return ScopeManager.get(page).getPageContext();
106 case PAGESCOPE:
107 return ScopeManager.get(page).getPageScope();
108 case PARAM:
109 return ScopeManager.get(page).getParam();
110 case PARAM_VALUES:
111 return ScopeManager.get(page).getParamValues();
112 case REQUEST_SCOPE:
113 return ScopeManager.get(page).getRequestScope();
114 case SESSION_SCOPE:
115 return ScopeManager.get(page).getSessionScope();
116 }
117 }
118 }
119 return null;
120 }
121
122 public Class getType(ELContext context, Object base, Object property)
123 throws NullPointerException , PropertyNotFoundException, ELException {
124 if (context == null) {
125 throw new NullPointerException ();
126 }
127
128 if (base == null && property != null) {
129 int idx = Arrays.binarySearch(SCOPE_NAMES, property.toString());
130 if (idx >= 0) {
131 context.setPropertyResolved(true);
132 }
133 }
134 return null;
135 }
136
137 public void setValue(ELContext context, Object base, Object property,
138 Object value) throws NullPointerException ,
139 PropertyNotFoundException, PropertyNotWritableException,
140 ELException {
141 if (context == null) {
142 throw new NullPointerException ();
143 }
144
145 if (base == null && property != null) {
146 int idx = Arrays.binarySearch(SCOPE_NAMES, property.toString());
147 if (idx >= 0) {
148 context.setPropertyResolved(true);
149 throw new PropertyNotWritableException();
150 }
151 }
152 }
153
154 public boolean isReadOnly(ELContext context, Object base, Object property)
155 throws NullPointerException , PropertyNotFoundException, ELException {
156 if (context == null) {
157 throw new NullPointerException ();
158 }
159
160 if (base == null && property != null) {
161 int idx = Arrays.binarySearch(SCOPE_NAMES, property.toString());
162 if (idx >= 0) {
163 context.setPropertyResolved(true);
164 return true;
165 }
166 }
167 return false;
168 }
169
170 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext context, Object base) {
171 List <FeatureDescriptor > feats = new ArrayList <FeatureDescriptor >(
172 SCOPE_NAMES.length);
173 FeatureDescriptor feat;
174 for (int i = 0; i < SCOPE_NAMES.length; i++) {
175 feat = new FeatureDescriptor ();
176 feat.setDisplayName(SCOPE_NAMES[i]);
177 feat.setExpert(false);
178 feat.setHidden(false);
179 feat.setName(SCOPE_NAMES[i]);
180 feat.setPreferred(true);
181 feat.setValue(RESOLVABLE_AT_DESIGN_TIME, Boolean.TRUE);
182 feat.setValue(TYPE, String .class);
183 feats.add(feat);
184 }
185 return feats.iterator();
186 }
187
188 public Class <String > getCommonPropertyType(ELContext context, Object base) {
189 if (base == null) {
190 return String .class;
191 }
192 return null;
193 }
194
195 private static class ScopeManager {
196 private final static String MNGR_KEY = ScopeManager.class.getName();
197
198 private final PageContext page;
199
200 private Map applicationScope;
201
202 private Map cookie;
203
204 private Map header;
205
206 private Map headerValues;
207
208 private Map initParam;
209
210 private Map pageScope;
211
212 private Map param;
213
214 private Map paramValues;
215
216 private Map requestScope;
217
218 private Map sessionScope;
219
220 public ScopeManager(PageContext page) {
221 this.page = page;
222 }
223
224 public static ScopeManager get(PageContext page) {
225 ScopeManager mngr = (ScopeManager) page.getAttribute(MNGR_KEY);
226 if (mngr == null) {
227 mngr = new ScopeManager(page);
228 page.setAttribute(MNGR_KEY, mngr);
229 }
230 return mngr;
231 }
232
233 public Map getApplicationScope() {
234 if (this.applicationScope == null) {
235 this.applicationScope = new ScopeMap() {
236 protected void setAttribute(String name, Object value) {
237 page.getServletContext().setAttribute(name, value);
238 }
239
240 protected void removeAttribute(String name) {
241 page.getServletContext().removeAttribute(name);
242 }
243
244 protected Enumeration getAttributeNames() {
245 return page.getServletContext().getAttributeNames();
246 }
247
248 protected Object getAttribute(String name) {
249 return page.getServletContext().getAttribute(name);
250 }
251 };
252 }
253 return this.applicationScope;
254 }
255
256 public Map getCookie() {
257 if (this.cookie == null) {
258 this.cookie = new ScopeMap() {
259 protected Enumeration getAttributeNames() {
260 Cookie [] c = ((HttpServletRequest ) page.getRequest())
261 .getCookies();
262 if (c != null) {
263 Vector v = new Vector ();
264 for (int i = 0; i < c.length; i++) {
265 v.add(c[i].getName());
266 }
267 return v.elements();
268 }
269 return null;
270 }
271
272 protected Object getAttribute(String name) {
273 Cookie [] c = ((HttpServletRequest ) page.getRequest())
274 .getCookies();
275 if (c != null) {
276 for (int i = 0; i < c.length; i++) {
277 if (name.equals(c[i].getName())) {
278 return c[i];
279 }
280 }
281 }
282 return null;
283 }
284
285 };
286 }
287 return this.cookie;
288 }
289
290 public Map getHeader() {
291 if (this.header == null) {
292 this.header = new ScopeMap() {
293 protected Enumeration getAttributeNames() {
294 return ((HttpServletRequest ) page.getRequest())
295 .getHeaderNames();
296 }
297
298 protected Object getAttribute(String name) {
299 return ((HttpServletRequest ) page.getRequest())
300 .getHeader(name);
301 }
302 };
303 }
304 return this.header;
305 }
306
307 public Map getHeaderValues() {
308 if (this.headerValues == null) {
309 this.headerValues = new ScopeMap() {
310 protected Enumeration getAttributeNames() {
311 return ((HttpServletRequest ) page.getRequest())
312 .getHeaderNames();
313 }
314
315 protected Object getAttribute(String name) {
316 Enumeration e = ((HttpServletRequest ) page.getRequest())
317 .getHeaders(name);
318 if (e != null) {
319 List list = new ArrayList ();
320 while (e.hasMoreElements()) {
321 list.add(e.nextElement().toString());
322 }
323 return (String []) list.toArray(new String [list
324 .size()]);
325 }
326 return null;
327 }
328
329 };
330 }
331 return this.headerValues;
332 }
333
334 public Map getInitParam() {
335 if (this.initParam == null) {
336 this.initParam = new ScopeMap() {
337 protected Enumeration getAttributeNames() {
338 return page.getServletContext().getInitParameterNames();
339 }
340
341 protected Object getAttribute(String name) {
342 return page.getServletContext().getInitParameter(name);
343 }
344 };
345 }
346 return this.initParam;
347 }
348
349 public PageContext getPageContext() {
350 return this.page;
351 }
352
353 public Map getPageScope() {
354 if (this.pageScope == null) {
355 this.pageScope = new ScopeMap() {
356 protected void setAttribute(String name, Object value) {
357 page.setAttribute(name, value);
358 }
359
360 protected void removeAttribute(String name) {
361 page.removeAttribute(name);
362 }
363
364 protected Enumeration getAttributeNames() {
365 return page
366 .getAttributeNamesInScope(PageContext.PAGE_SCOPE);
367 }
368
369 protected Object getAttribute(String name) {
370 return page.getAttribute(name);
371 }
372 };
373 }
374 return this.pageScope;
375 }
376
377 public Map getParam() {
378 if (this.param == null) {
379 this.param = new ScopeMap() {
380 protected Enumeration getAttributeNames() {
381 return page.getRequest().getParameterNames();
382 }
383
384 protected Object getAttribute(String name) {
385 return page.getRequest().getParameter(name);
386 }
387 };
388 }
389 return this.param;
390 }
391
392 public Map getParamValues() {
393 if (this.paramValues == null) {
394 this.paramValues = new ScopeMap() {
395 protected Object getAttribute(String name) {
396 return page.getRequest().getParameterValues(name);
397 }
398
399 protected Enumeration getAttributeNames() {
400 return page.getRequest().getParameterNames();
401 }
402 };
403 }
404 return this.paramValues;
405 }
406
407 public Map getRequestScope() {
408 if (this.requestScope == null) {
409 this.requestScope = new ScopeMap() {
410 protected void setAttribute(String name, Object value) {
411 page.getRequest().setAttribute(name, value);
412 }
413
414 protected void removeAttribute(String name) {
415 page.getRequest().removeAttribute(name);
416 }
417
418 protected Enumeration getAttributeNames() {
419 return page.getRequest().getAttributeNames();
420 }
421
422 protected Object getAttribute(String name) {
423 return page.getRequest().getAttribute(name);
424 }
425 };
426 }
427 return this.requestScope;
428 }
429
430 public Map getSessionScope() {
431 if (this.sessionScope == null) {
432 this.sessionScope = new ScopeMap() {
433 protected void setAttribute(String name, Object value) {
434 ((HttpServletRequest ) page.getRequest()).getSession()
435 .setAttribute(name, value);
436 }
437
438 protected void removeAttribute(String name) {
439 HttpSession session = page.getSession();
440 if (session != null) {
441 session.removeAttribute(name);
442 }
443 }
444
445 protected Enumeration getAttributeNames() {
446 HttpSession session = page.getSession();
447 if (session != null) {
448 return session.getAttributeNames();
449 }
450 return null;
451 }
452
453 protected Object getAttribute(String name) {
454 HttpSession session = page.getSession();
455 if (session != null) {
456 return session.getAttribute(name);
457 }
458 return null;
459 }
460 };
461 }
462 return this.sessionScope;
463 }
464 }
465
466 private abstract static class ScopeMap extends AbstractMap {
467
468 protected abstract Enumeration getAttributeNames();
469
470 protected abstract Object getAttribute(String name);
471
472 protected void removeAttribute(String name) {
473 throw new UnsupportedOperationException ();
474 }
475
476 protected void setAttribute(String name, Object value) {
477 throw new UnsupportedOperationException ();
478 }
479
480 public final Set entrySet() {
481 Enumeration e = getAttributeNames();
482 Set set = new HashSet ();
483 if (e != null) {
484 while (e.hasMoreElements()) {
485 set.add(new ScopeEntry((String ) e.nextElement()));
486 }
487 }
488 return set;
489 }
490
491 private class ScopeEntry implements Map.Entry {
492
493 private final String key;
494
495 public ScopeEntry(String key) {
496 this.key = key;
497 }
498
499 public Object getKey() {
500 return (Object ) this.key;
501 }
502
503 public Object getValue() {
504 return getAttribute(this.key);
505 }
506
507 public Object setValue(Object value) {
508 if (value == null) {
509 removeAttribute(this.key);
510 } else {
511 setAttribute(this.key, value);
512 }
513 return null;
514 }
515
516 public boolean equals(Object obj) {
517 return (obj != null && this.hashCode() == obj.hashCode());
518 }
519
520 public int hashCode() {
521 return this.key.hashCode();
522 }
523
524 }
525
526 public final Object get(Object key) {
527 if (key != null) {
528 return getAttribute(key.toString());
529 }
530 return null;
531 }
532
533 public final Object put(Object key, Object value) {
534 if (key == null) {
535 throw new NullPointerException ();
536 }
537 if (value == null) {
538 this.removeAttribute(key.toString());
539 } else {
540 this.setAttribute(key.toString(), value);
541 }
542 return null;
543 }
544
545 public final Object remove(Object key) {
546 if (key == null) {
547 throw new NullPointerException ();
548 }
549 this.removeAttribute(key.toString());
550 return null;
551 }
552
553 }
554
555 }
556 |
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