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1
18 package org.apache.beehive.netui.pageflow.internal;
19
20 import java.util.Map  ;
21 import java.util.Enumeration ;
22 import java.util.HashMap ;
23
24 import javax.servlet.ServletContext ;
25 import javax.servlet.jsp.el.ExpressionEvaluator ;
26 import javax.servlet.jsp.el.VariableResolver ;
27 import javax.servlet.jsp.el.ELException ;
28 import javax.servlet.http.HttpServletRequest ;
29 import javax.servlet.http.HttpSession ;
30 import javax.servlet.http.Cookie ;
31
32 import org.apache.beehive.netui.util.logging.Logger;
33 import org.apache.commons.el.ExpressionEvaluatorImpl;
34 import org.apache.commons.el.EnumeratedMap;
35
36
42 public class InternalExpressionUtils
43 {
44 private static final Logger _logger = Logger.getInstance(InternalExpressionUtils.class);
45
46 public static final boolean evaluateCondition(String expression,
47 Object actionForm,
48 HttpServletRequest request,
49 ServletContext servletContext)
50 throws ELException
51 {
52 return ((Boolean )evaluate(expression, Boolean .class, actionForm, request, servletContext)).booleanValue();
53 }
54
55 public static final String evaluateMessage(String expression, Object actionForm, HttpServletRequest request,
56 ServletContext servletContext)
57 throws ELException
58 {
59 return (String )evaluate(expression, String .class, actionForm, request, servletContext);
60 }
61
62
63 private InternalExpressionUtils() {}
64
65 private static final Object evaluate(String expression, Class expectedType, Object actionForm, HttpServletRequest request, ServletContext servletContext)
66 throws ELException
67 {
68 ExpressionEvaluator ee = getExpressionEvaluator();
70 return ee.evaluate(expression, expectedType, getVariableResolver(actionForm, request, servletContext), null);
71 }
72
73 private static final ExpressionEvaluator getExpressionEvaluator()
74 {
75 return new ExpressionEvaluatorImpl();
76 }
77
78 private static final VariableResolver getVariableResolver(Object actionForm, HttpServletRequest request, ServletContext servletContext)
79 {
80 return new SimpleActionVariableResolver(actionForm, request, servletContext);
81 }
82
83 private static class SimpleActionVariableResolver
84 implements VariableResolver
85 {
86 private Object _actionForm = null;
87 private HttpServletRequest _request = null;
88 private ServletContext _servletContext = null;
89
90 private SimpleActionVariableResolver(Object actionForm, HttpServletRequest request, ServletContext servletContext)
91 {
92 _actionForm = actionForm;
93 _request = request;
94 _servletContext = servletContext;
95 }
96
97 public Object resolveVariable(String name)
98 {
99 if(name.equals("actionForm"))
101 return _actionForm;
102 else if(name.equals("requestScope"))
103 return buildRequestScopeMap(_request);
104 else if(name.equals("sessionScope"))
105 return buildSessionScopeMap(_request);
106 else if(name.equals("applicationScope"))
107 return buildServletContextMap(_servletContext);
108 else if(name.equals("param"))
109 return buildParamMap(_request);
110 else if(name.equals("paramValues"))
111 return buildParamsMap(_request);
112 else if(name.equals("header"))
113 return buildHeaderMap(_request);
114 else if(name.equals("headerValues"))
115 return buildHeadersMap(_request);
116 else if(name.equals("cookie"))
117 return buildCookieMap(_request);
118 else if(name.equals("initParam"))
119 return buildInitParamMap(_servletContext);
120 else if(_request.getAttribute(name) != null)
124 return _request.getAttribute(name);
125 else if(_request.getSession(false) != null && _request.getSession(false).getAttribute(name) != null)
126 return _request.getSession(false).getAttribute(name);
127 else return _servletContext.getAttribute(name);
128 }
129
130 private static final Map buildCookieMap(HttpServletRequest httpServletRequest)
131 {
132 HttpServletRequest servletRequest = httpServletRequest;
133 Map cookieMap = new HashMap ();
134 Cookie [] cookies = servletRequest.getCookies();
135 for(int i = 0; i < cookies.length; i++)
136 {
137 if(!cookieMap.containsKey(cookies[i].getName()))
138 cookieMap.put(cookies[i].getName(), cookies[i]);
139 }
140 return cookieMap;
141 }
142
143 private static final Map buildHeadersMap(HttpServletRequest httpServletRequest)
144 {
145 final HttpServletRequest _servletRequest = httpServletRequest;
146 return new EnumeratedMap()
147 {
148 public Enumeration enumerateKeys()
149 {
150 return _servletRequest.getHeaderNames();
151 }
152
153 public Object getValue(Object key)
154 {
155 return (key instanceof String ? _servletRequest.getHeaders((String )key) : null);
156 }
157
158 public boolean isMutable() {return false;}
159 };
160 }
161
162 private static final Map buildHeaderMap(HttpServletRequest httpServletRequest)
163 {
164 final HttpServletRequest _servletRequest = httpServletRequest;
165 return new EnumeratedMap()
166 {
167 public Enumeration enumerateKeys()
168 {
169 return _servletRequest.getHeaderNames();
170 }
171
172 public Object getValue(Object key)
173 {
174 return (key instanceof String ? _servletRequest.getHeader((String )key) : null);
175 }
176
177 public boolean isMutable() {return false;}
178 };
179 }
180
181 private static final Map buildInitParamMap(ServletContext servletContext)
182 {
183 final ServletContext _servletContext = servletContext;
184 return new EnumeratedMap()
185 {
186 public Enumeration enumerateKeys()
187 {
188 return _servletContext.getInitParameterNames();
189 }
190
191 public Object getValue(Object key)
192 {
193 return (key instanceof String ? _servletContext.getInitParameter((String )key) : null);
194 }
195
196 public boolean isMutable() {return false;}
197 };
198 }
199
200 private static final Map buildParamsMap(HttpServletRequest servletRequest)
201 {
202 final HttpServletRequest _servletRequest = servletRequest;
203 return new EnumeratedMap()
204 {
205 public Enumeration enumerateKeys()
206 {
207 return _servletRequest.getParameterNames();
208 }
209
210 public Object getValue(Object key)
211 {
212 return (key instanceof String ? _servletRequest.getParameterValues((String )key) : null);
213 }
214
215 public boolean isMutable() {return false;}
216 };
217 }
218
219 private static final Map buildParamMap(HttpServletRequest servletRequest)
220 {
221 final HttpServletRequest _servletRequest = servletRequest;
222 return new EnumeratedMap()
223 {
224 public Enumeration enumerateKeys()
225 {
226 return _servletRequest.getParameterNames();
227 }
228
229 public Object getValue(Object key)
230 {
231 return (key instanceof String ? _servletRequest.getParameter((String )key) : null);
232 }
233
234 public boolean isMutable() {return false;}
235 };
236 }
237
238 private static final Map buildRequestScopeMap(HttpServletRequest servletRequest)
239 {
240 final HttpServletRequest _servletRequest = servletRequest;
241 return new EnumeratedMap()
242 {
243 public Enumeration enumerateKeys()
244 {
245 return _servletRequest.getAttributeNames();
246 }
247
248 public Object getValue(Object key)
249 {
250 return (key instanceof String ? _servletRequest.getAttribute((String )key) : null);
251 }
252
253 public boolean isMutable() {return false;}
254 };
255 }
256
257 private static final Map buildSessionScopeMap(HttpServletRequest servletRequest)
258 {
259 if(servletRequest.getSession(false) == null)
260 return null;
261
262 final HttpSession _session = servletRequest.getSession(false);
263 return new EnumeratedMap()
264 {
265 public Enumeration enumerateKeys()
266 {
267 return _session.getAttributeNames();
268 }
269
270 public Object getValue(Object key)
271 {
272 return (key instanceof String ? _session.getAttribute((String )key) : null);
273 }
274
275 public boolean isMutable() {return false;}
276 };
277 }
278
279 private static final Map buildServletContextMap(ServletContext servletContext)
280 {
281 final ServletContext _servletContext = servletContext;
282 return new EnumeratedMap()
283 {
284 public Enumeration enumerateKeys()
285 {
286 return _servletContext.getAttributeNames();
287 }
288
289 public Object getValue(Object key)
290 {
291 return (key instanceof String ? _servletContext.getAttribute((String )key) : null);
292 }
293
294 public boolean isMutable() {return false;}
295 };
296 }
297 }
298 }
299 |
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