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1
29
30 package com.caucho.jsp.el;
31
32 import com.caucho.el.Expr;
33 import com.caucho.vfs.WriteStream;
34
35 import javax.el.ELContext;
36 import javax.el.ELException;
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 import java.io.IOException ;
43 import java.util.*;
44
45 public class ImplicitFieldExpr extends Expr {
46 private int _index;
47
48 private Expr _field;
49
50 public ImplicitFieldExpr(int index, Expr field)
51 {
52 _index = index;
53 _field = field;
54 }
55
56
61 @Override
62 public Object getValue(ELContext env)
63 throws ELException
64 {
65 PageContext page = (PageContext ) env.getContext(JspContext .class);
66
67 Object fieldValue = _field.evalObject(env);
68
69 if (fieldValue == null)
70 return null;
71
72 String fieldString = toString(fieldValue, env);
73
74 switch (_index) {
75 case ImplicitObjectExpr.APPLICATION_SCOPE:
76 return page.getServletContext().getAttribute(fieldString);
77
78 case ImplicitObjectExpr.SESSION_SCOPE:
79 {
80 HttpSession session = page.getSession();
81
82 if (session != null) {
83 return session.getAttribute(fieldString);
84 }
85 else
86 return null;
87 }
88
89 case ImplicitObjectExpr.REQUEST_SCOPE:
90 {
91 return page.getRequest().getAttribute(fieldString);
92 }
93
94 case ImplicitObjectExpr.PAGE_SCOPE:
95 return page.getAttribute(fieldString);
96
97 case ImplicitObjectExpr.PARAM:
98 return page.getRequest().getParameter(fieldString);
99
100 case ImplicitObjectExpr.PARAM_VALUES:
101 return page.getRequest().getParameterValues(fieldString);
102
103 case ImplicitObjectExpr.HEADER:
104 return ((HttpServletRequest ) page.getRequest()).getHeader(fieldString);
105
106 case ImplicitObjectExpr.HEADER_VALUES: {
107 Enumeration e =
108 ((HttpServletRequest ) page.getRequest()).getHeaders(fieldString);
109
110 if (e == null)
111 return null;
112
113 if (! e.hasMoreElements())
114 return null;
115
116 ArrayList<String > list = new ArrayList<String >();
117
118 while (e.hasMoreElements())
119 list.add((String ) e.nextElement());
120
121 return list.toArray(new String [list.size()]);
122 }
123
124 case ImplicitObjectExpr.INIT_PARAM:
125 return page.getServletContext().getInitParameter(fieldString);
126
127 case ImplicitObjectExpr.COOKIE: {
128 Cookie []cookies = ((HttpServletRequest ) page.getRequest()).getCookies();
129 if (cookies == null)
130 return null;
131
132 for (int i = 0; i < cookies.length; i++) {
133 if (cookies[i].getName().equals(fieldString))
134 return cookies[i];
135 }
136
137 return null;
138 }
139 }
140
141 throw new UnsupportedOperationException ();
142 }
143
144 public String toString()
145 {
146 return "implicit_" + _index + "[" + _field + "]";
147 }
148
149
152 @Override
153 public void printCreate(WriteStream os)
154 throws IOException
155 {
156 os.print("new com.caucho.jsp.el.ImplicitFieldExpr(");
157 os.print(_index);
158 os.print(", ");
159 _field.printCreate(os);
160 os.print(")");
161 }
162
163 public static class AttributeMap extends AbstractMap {
164 private PageContext _pageContext;
165 private int _scope;
166
167 AttributeMap(PageContext pageContext, int scope)
168 {
169 _pageContext = pageContext;
170 _scope = scope;
171 }
172
173 public Object get(Object key)
174 {
175 return _pageContext.getAttribute((String ) key, _scope);
176 }
177
178 public Object put(Object key, Object value)
179 {
180 _pageContext.setAttribute((String ) key, value, _scope);
181
182 return null;
183 }
184
185 private EntrySet _entrySet;
186
187 public Set entrySet()
188 {
189 if (_entrySet == null)
190 _entrySet = new EntrySet();
191
192 return _entrySet;
193 }
194
195 public class EntrySet extends AbstractSet {
196 public int size()
197 {
198 Enumeration e = _pageContext.getAttributeNamesInScope(_scope);
199 int i = 0;
200 while (e.hasMoreElements()) {
201 e.nextElement();
202 i++;
203 }
204
205 return i;
206 }
207
208 public Iterator iterator()
209 {
210 return new EntryIterator();
211 }
212 }
213
214 public class EntryIterator implements Iterator, Map.Entry {
215 Enumeration _e;
216 String _name;
217 Object _value;
218
219 EntryIterator()
220 {
221 _e = _pageContext.getAttributeNamesInScope(_scope);
222 }
223
224 public boolean hasNext()
225 {
226 return _e.hasMoreElements();
227 }
228
229 public Object next()
230 {
231 _name = (String ) _e.nextElement();
232 _value = _pageContext.getAttribute(_name, _scope);
233
234 return this;
235 }
236
237 public void remove()
238 {
239 throw new UnsupportedOperationException ();
240 }
241
242 public Object getKey()
243 {
244 return _name;
245 }
246
247 public Object getValue()
248 {
249 return _value;
250 }
251
252 public Object setValue(Object value)
253 {
254 _pageContext.setAttribute(_name, value, _scope);
255
256 Object oldValue = _value;
257 _value = value;
258
259 return oldValue;
260 }
261
262 public int hashCode()
263 {
264 return _name.hashCode();
265 }
266
267 public boolean equals(Object obj)
268 {
269 if (! (obj instanceof EntryIterator))
270 return false;
271
272 EntryIterator entry = (EntryIterator) obj;
273
274 return (_name.equals(entry._name) &&
275 (_value == null && entry._value == null ||
276 _value != null && _value.equals(entry._value)));
277 }
278 }
279 }
280 }
281 |
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