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1 package com.quadcap.http.servlets.jsp;
2
3
40
41 import java.io.IOException  ;
42 import java.io.PrintWriter ;
43
44 import java.util.Enumeration ;
45 import java.util.Hashtable ;
46 import java.util.Vector ;
47
48 import javax.servlet.RequestDispatcher ;
49 import javax.servlet.Servlet ;
50 import javax.servlet.ServletConfig ;
51 import javax.servlet.ServletContext ;
52 import javax.servlet.ServletException ;
53 import javax.servlet.ServletRequest ;
54 import javax.servlet.ServletResponse ;
55
56 import javax.servlet.http.HttpServletRequest ;
57 import javax.servlet.http.HttpServletResponse ;
58 import javax.servlet.http.HttpSession ;
59
60 import com.quadcap.http.server22.HttpResponse;
61
62 import com.quadcap.util.Debug;
63
64
69 public class PageContext extends javax.servlet.jsp.PageContext {
70 Hashtable pageAttributes = null;
71 Servlet servlet;
72 HttpServletRequest request;
73 HttpServletResponse response;
74 HttpSession session;
75 String errorPageURL;
76 boolean needsSession;
77 int bufferSize;
78 boolean autoFlush;
79 javax.servlet.jsp.JspWriter out;
80
81 public void initialize(Servlet servlet, ServletRequest request,
82 ServletResponse response,
83 String errorPageURL, boolean needsSession,
84 int bufferSize,
85 boolean autoFlush)
86 throws IOException , IllegalStateException , IllegalArgumentException
87 {
88 this.servlet = servlet;
89 this.request = (HttpServletRequest )request;
90 this.response = (HttpServletResponse )response;
91 this.errorPageURL = errorPageURL;
92 this.needsSession = needsSession;
93 this.bufferSize = bufferSize;
94 this.autoFlush = autoFlush;
95 this.session = null;
96
97 if (response instanceof HttpResponse) {
98 HttpResponse qresp = (HttpResponse)response;
99 this.out = qresp.getJspWriter(bufferSize, autoFlush);
100 } else {
101 this.out = new JspWriter(response.getWriter(), bufferSize, autoFlush);
102 }
103 }
104
105 public void release() {
106 this.servlet = null;
107 this.request = null;
108 this.response = null;
109 this.errorPageURL = null;
110 this.session = null;
111 }
112
113 public void setAttribute(String name, Object val) {
114 setAttribute(name, val, PAGE_SCOPE);
115 }
116
117 public void setAttribute(String name, Object val, int scope) {
118 switch (scope) {
119 case PAGE_SCOPE:
120 if (pageAttributes == null) pageAttributes = new Hashtable ();
121 pageAttributes.put(name, val);
122 break;
123 case REQUEST_SCOPE:
124 request.setAttribute(name, val);
125 break;
126 case SESSION_SCOPE:
127 if (session != null) session.putValue(name, val);
128 break;
129 case APPLICATION_SCOPE:
130 getServletContext().setAttribute(name, val);
131 }
132 }
133
134 public Object getAttribute(String name) {
135 return getAttribute(name, PAGE_SCOPE);
136 }
137
138 public Object getAttribute(String name, int scope) {
139 switch (scope) {
140 case PAGE_SCOPE:
141 if (pageAttributes != null) return pageAttributes.get(name);
142 break;
143 case REQUEST_SCOPE:
144 return request.getAttribute(name);
145 case SESSION_SCOPE:
146 if (session != null) return session.getValue(name);
147 break;
148 case APPLICATION_SCOPE:
149 return getServletContext().getAttribute(name);
150 }
151 return null;
152 }
153
154 public Object findAttribute(String name) {
155 Object obj = null;
156 for (int i = 0; obj == null && i < 4; i++) {
157 obj = getAttribute(name, i);
158 }
159 return obj;
160 }
161
162 public void removeAttribute(String name) {
163 removeAttribute(name, PAGE_SCOPE);
164 }
165
166 public void removeAttribute(String name, int scope) {
167 switch (scope) {
168 case PAGE_SCOPE:
169 if (pageAttributes != null) pageAttributes.remove(name);
170 break;
171 case REQUEST_SCOPE:
172 request.setAttribute(name, ""); break;
174 case SESSION_SCOPE:
175 if (session != null) session.removeValue(name);
176 break;
177 case APPLICATION_SCOPE:
178 getServletContext().removeAttribute(name);
179 }
180 }
181
182 public int getAttributesScope(String name) {
183 int scope = 0;
184 for (int i = 0; scope == 0 && i < 4; i++) {
185 if (getAttribute(name, i) != null) {
186 scope = i+1;
187 }
188 }
189 return scope;
190 }
191
192 public Enumeration getAttributeNamesInScope(int scope) {
193 switch (scope) {
194 case PAGE_SCOPE:
195 if (pageAttributes != null) return pageAttributes.keys();
196 break;
197 case REQUEST_SCOPE:
198 return request.getAttributeNames();
199 case SESSION_SCOPE:
200 Vector v = new Vector ();
201 if (session != null) {
202 String [] s = session.getValueNames();
203 for (int i = 0; i < s.length; i++) v.addElement(s[i]);
204 }
205 return v.elements();
206 case APPLICATION_SCOPE:
207 return getServletContext().getAttributeNames();
208 }
209 return new Vector ().elements();
210 }
211
212 public javax.servlet.jsp.JspWriter getOut() {
213 return out;
214 }
215
216 public HttpSession getSession() {
217 if (session == null) session = new JspSession(request);
218 return session;
219 }
220
221 public Object getPage() {
222 return servlet;
223 }
224
225 public ServletRequest getRequest() {
226 return request;
227 }
228
229 public ServletResponse getResponse() {
230 return response;
231 }
232
233 public Exception getException() {
234 return (Exception )request.getAttribute("exception");
235 }
236
237 public ServletConfig getServletConfig() {
238 return servlet.getServletConfig();
239 }
240
241 public ServletContext getServletContext() {
242 return getServletConfig().getServletContext();
243 }
244
245 final String relativize(String url) throws ServletException {
246 if (url.charAt(0) != '/') {
247 String p = request.getServletPath();
248 int idx = p.lastIndexOf('/');
249 if (idx >= 0) {
250 url = p.substring(0, idx) + "/" + url;
251 }
252 }
253 return url;
254 }
255
256 public void forward(String url) throws ServletException , IOException {
257 url = relativize(url);
258 RequestDispatcher rd = getServletContext().getRequestDispatcher(url);
259 out.clearBuffer();
260 rd.forward(request, response);
261 }
262
263 public void include(String url) throws ServletException , IOException {
264 url = relativize(url);
265 RequestDispatcher rd = getServletContext().getRequestDispatcher(url);
266 rd.include(request, response);
267 }
268
269 public void handleFinally() throws IOException {
270 if (autoFlush) {
271 out.flush();
272 }
273 }
274
275 public void handlePageException(Exception e)
276 throws ServletException , IOException
277 {
278 if (errorPageURL == null) {
279 if (Trace.level() > 1) {
280 Debug.print(e);
281 }
282 response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
283 PrintWriter w = response.getWriter();
284 w.println("<html><head><title>");
285 w.println(e.toString());
286 w.println("</title></head><body>");
287 w.println("<pre>");
288 e.printStackTrace(w);
289 w.println("</pre></body></html>");
290 w.flush();
291 } else {
292 request.setAttribute("exception", e);
293 forward(errorPageURL);
294 }
295 }
296 }
297 |
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