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1
52
53 package freemarker.ext.jsp;
54
55 import java.io.IOException  ;
56 import java.util.ArrayList ;
57 import java.util.Collections ;
58 import java.util.Enumeration ;
59 import java.util.List ;
60
61 import javax.servlet.GenericServlet ;
62 import javax.servlet.Servlet ;
63 import javax.servlet.ServletConfig ;
64 import javax.servlet.ServletContext ;
65 import javax.servlet.ServletException ;
66 import javax.servlet.ServletRequest ;
67 import javax.servlet.ServletResponse ;
68 import javax.servlet.http.HttpServletRequest ;
69 import javax.servlet.http.HttpServletResponse ;
70 import javax.servlet.http.HttpSession ;
71 import javax.servlet.jsp.JspWriter ;
72 import javax.servlet.jsp.PageContext ;
73 import javax.servlet.jsp.tagext.Tag ;
74
75 import freemarker.core.Environment;
76 import freemarker.ext.servlet.FreemarkerServlet;
77 import freemarker.ext.servlet.HttpRequestHashModel;
78 import freemarker.ext.servlet.ServletContextHashModel;
79 import freemarker.ext.util.WrapperTemplateModel;
80 import freemarker.template.ObjectWrapper;
81 import freemarker.template.TemplateBooleanModel;
82 import freemarker.template.TemplateHashModelEx;
83 import freemarker.template.TemplateModel;
84 import freemarker.template.TemplateModelException;
85 import freemarker.template.TemplateModelIterator;
86 import freemarker.template.TemplateNumberModel;
87 import freemarker.template.TemplateScalarModel;
88 import freemarker.template.utility.UndeclaredThrowableException;
89
90
94 class FreeMarkerPageContext extends PageContext implements TemplateModel
95 {
96 private static final String NO_FM_SERVLET =
97 "FreeMarker JSP taglib integration can not be used outside the " +
98 "FreemarkerServlet environment.";
99
100 private final Environment environment;
101 private List tags = new ArrayList ();
102 private List outs = new ArrayList ();
103 private final GenericServlet servlet;
104 private HttpSession session;
105 private final HttpServletRequest request;
106 private final HttpServletResponse response;
107 private final ObjectWrapper wrapper;
108 private JspWriter jspOut;
109
110 static FreeMarkerPageContext getCurrentPageContext() throws TemplateModelException {
111 Environment env = Environment.getCurrentEnvironment();
112 TemplateModel pageContextModel = env.getGlobalVariable(PAGECONTEXT);
113 if(pageContextModel instanceof FreeMarkerPageContext) {
114 return (FreeMarkerPageContext)pageContextModel;
115 }
116 FreeMarkerPageContext pageContext = new FreeMarkerPageContext();
117 env.setGlobalVariable(PAGECONTEXT, pageContext);
118 return pageContext;
119 }
120
121 private FreeMarkerPageContext()
122 throws
123 TemplateModelException
124 {
125 environment = Environment.getCurrentEnvironment();
126
127 TemplateModel appModel =
128 environment.getGlobalVariable(FreemarkerServlet.KEY_APPLICATION);
129 if(appModel instanceof ServletContextHashModel) {
130 this.servlet = ((ServletContextHashModel)appModel).getServlet();
131 }
132 else {
133 throw new
134 TemplateModelException(
135 "Could not find the Application data model." +
136 NO_FM_SERVLET);
137 }
138
139 TemplateModel requestModel =
140 environment.getGlobalVariable(FreemarkerServlet.KEY_REQUEST);
141 if(requestModel instanceof HttpRequestHashModel) {
142 HttpRequestHashModel reqHash = (HttpRequestHashModel)requestModel;
143 this.request = reqHash.getRequest();
144 this.session = request.getSession(false);
145 this.response = reqHash.getResponse();
146 this.wrapper = reqHash.getObjectWrapper();
147 }
148 else {
149 throw new
150 TemplateModelException(
151 "Could not find the Request data model." +
152 NO_FM_SERVLET);
153 }
154
155 setAttribute(REQUEST, request);
157 setAttribute(RESPONSE, response);
158 if (session != null)
159 setAttribute(SESSION, session);
160 setAttribute(PAGE, servlet);
161 setAttribute(CONFIG, servlet.getServletConfig());
162 setAttribute(PAGECONTEXT, this);
163 setAttribute(APPLICATION, servlet.getServletContext());
164 }
165
166 ObjectWrapper getObjectWrapper() {
167 return wrapper;
168 }
169
170 public void initialize(
171 Servlet servlet, ServletRequest request, ServletResponse response,
172 String errorPageURL, boolean needsSession, int bufferSize,
173 boolean autoFlush)
174 {
175 throw new UnsupportedOperationException ();
176 }
177
178 public void release() {
179 }
180
181 public void setAttribute(String name, Object value) {
182 setAttribute(name, value, PAGE_SCOPE);
183 }
184
185 public void setAttribute(String name, Object value, int scope) {
186 switch(scope) {
187 case PAGE_SCOPE: {
188 try {
189 environment.setGlobalVariable(name, wrapper.wrap(value));
190 break;
191 }
192 catch(TemplateModelException e) {
193 throw new UndeclaredThrowableException(e);
194 }
195 }
196 case REQUEST_SCOPE: {
197 getRequest().setAttribute(name, value);
198 break;
199 }
200 case SESSION_SCOPE: {
201 getSession(true).setAttribute(name, value);
202 break;
203 }
204 case APPLICATION_SCOPE: {
205 getServletContext().setAttribute(name, value);
206 break;
207 }
208 default: {
209 throw new IllegalArgumentException ("Invalid scope " + scope);
210 }
211 }
212 }
213
214 public Object getAttribute(String name)
215 {
216 return getAttribute(name, PAGE_SCOPE);
217 }
218
219 public Object getAttribute(String name, int scope)
220 {
221 switch (scope) {
222 case PAGE_SCOPE: {
223 try {
224 TemplateModel m = environment.getGlobalNamespace().get(name);
225 if (m instanceof WrapperTemplateModel) {
226 return ((WrapperTemplateModel) m).getWrappedObject();
227 } else if (m instanceof TemplateScalarModel) {
228 return ((TemplateScalarModel) m).getAsString();
229 } else if (m instanceof TemplateNumberModel) {
230 return ((TemplateNumberModel) m).getAsNumber();
231 } else if (m instanceof TemplateBooleanModel) {
232 return ((TemplateBooleanModel) m).getAsBoolean() ? Boolean.TRUE : Boolean.FALSE;
233 } else {
234 return m;
235 }
236 }
237 catch (TemplateModelException e) {
238 throw new UndeclaredThrowableException(e);
239 }
240 }
241 case REQUEST_SCOPE: {
242 return getRequest().getAttribute(name);
243 }
244 case SESSION_SCOPE: {
245 HttpSession session = getSession(false);
246 if(session == null) {
247 return null;
248 }
249 return session.getAttribute(name);
250 }
251 case APPLICATION_SCOPE: {
252 return getServletContext().getAttribute(name);
253 }
254 default: {
255 throw new IllegalArgumentException ("Invalid scope " + scope);
256 }
257 }
258 }
259
260 public Object findAttribute(String name)
261 {
262 Object retval = getAttribute(name, PAGE_SCOPE);
263 if(retval != null) return retval;
264 retval = getAttribute(name, REQUEST_SCOPE);
265 if(retval != null) return retval;
266 retval = getAttribute(name, SESSION_SCOPE);
267 if(retval != null) return retval;
268 return getAttribute(name, APPLICATION_SCOPE);
269 }
270
271 public void removeAttribute(String name) {
272 removeAttribute(name, PAGE_SCOPE);
273 removeAttribute(name, REQUEST_SCOPE);
274 removeAttribute(name, SESSION_SCOPE);
275 removeAttribute(name, APPLICATION_SCOPE);
276 }
277
278 public void removeAttribute(String name, int scope) {
279 switch(scope) {
280 case PAGE_SCOPE: {
281 environment.getGlobalNamespace().remove(name);
282 break;
283 }
284 case REQUEST_SCOPE: {
285 getRequest().removeAttribute(name);
286 break;
287 }
288 case SESSION_SCOPE: {
289 HttpSession session = getSession(false);
290 if(session != null) {
291 session.removeAttribute(name);
292 }
293 break;
294 }
295 case APPLICATION_SCOPE: {
296 getServletContext().removeAttribute(name);
297 break;
298 }
299 default: {
300 throw new IllegalArgumentException ("Invalid scope: " + scope);
301 }
302 }
303 }
304
305 public int getAttributesScope(String name) {
306 if(getAttribute(name, PAGE_SCOPE) != null) return PAGE_SCOPE;
307 if(getAttribute(name, REQUEST_SCOPE) != null) return REQUEST_SCOPE;
308 if(getAttribute(name, SESSION_SCOPE) != null) return SESSION_SCOPE;
309 if(getAttribute(name, APPLICATION_SCOPE) != null) return APPLICATION_SCOPE;
310 return 0;
311 }
312
313 public Enumeration getAttributeNamesInScope(int scope) {
314 switch(scope) {
315 case PAGE_SCOPE: {
316 try {
317 return
318 new TemplateHashModelExEnumeration(environment.getGlobalNamespace());
319 }
320 catch(TemplateModelException e) {
321 throw new UndeclaredThrowableException(e);
322 }
323 }
324 case REQUEST_SCOPE: {
325 return getRequest().getAttributeNames();
326 }
327 case SESSION_SCOPE: {
328 HttpSession session = getSession(false);
329 if(session != null) {
330 return session.getAttributeNames();
331 }
332 return Collections.enumeration(Collections.EMPTY_SET);
333 }
334 case APPLICATION_SCOPE: {
335 return getServletContext().getAttributeNames();
336 }
337 default: {
338 throw new IllegalArgumentException ("Invalid scope " + scope);
339 }
340 }
341 }
342
343 public JspWriter getOut() {
344 return jspOut;
345 }
346
347 private HttpSession getSession(boolean create) {
348 if(session == null) {
349 session = request.getSession(create);
350 if(session != null) {
351 setAttribute(SESSION, session);
352 }
353 }
354 return session;
355 }
356
357 public HttpSession getSession() {
358 return getSession(false);
359 }
360
361 public Object getPage() {
362 return servlet;
363 }
364
365 public ServletRequest getRequest() {
366 return request;
367 }
368
369 public ServletResponse getResponse() {
370 return response;
371 }
372
373 public Exception getException() {
374 throw new UnsupportedOperationException ();
375 }
376
377 public ServletConfig getServletConfig() {
378 return servlet.getServletConfig();
379 }
380
381 public ServletContext getServletContext() {
382 return servlet.getServletContext();
383 }
384
385 public void forward(String url) throws ServletException , IOException {
386 request.getRequestDispatcher(url).forward(request, response);
388 }
389
390 public void include(String url) throws ServletException , IOException {
391 request.getRequestDispatcher(url).include(request, response);
393 }
394
395 public void handlePageException(Exception e) {
396 throw new UnsupportedOperationException ();
397 }
398
399 public void handlePageException(Throwable e) {
400 throw new UnsupportedOperationException ();
401 }
402
403 Tag peekTopTag() {
404 return tags.isEmpty() ? null : (Tag ) tags.get(tags.size() - 1);
405 }
406
407 void popTopTag() {
408 tags.remove(tags.size() - 1);
409 }
410
411 void popWriter() {
412 jspOut = (JspWriter )outs.remove(outs.size() - 1);
413 setAttribute(OUT, jspOut);
414 }
415
416 void pushTopTag(Tag tag) {
417 tags.add(tag);
418 }
419
420 void pushWriter(JspWriter out) {
421 outs.add(jspOut);
422 jspOut = out;
423 setAttribute(OUT, jspOut);
424 }
425
426 private static class TemplateHashModelExEnumeration implements Enumeration {
427 private final TemplateModelIterator it;
428
429 private TemplateHashModelExEnumeration(TemplateHashModelEx hashEx) throws TemplateModelException {
430 it = hashEx.keys().iterator();
431 }
432
433 public boolean hasMoreElements() {
434 try {
435 return it.hasNext();
436 } catch (TemplateModelException tme) {
437 throw new UndeclaredThrowableException(tme);
438 }
439 }
440
441 public Object nextElement() {
442 try {
443 return ((TemplateScalarModel) it.next()).getAsString();
444 } catch (TemplateModelException tme) {
445 throw new UndeclaredThrowableException(tme);
446 }
447 }
448 }
449 }
450 |
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