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1
29
30 package com.caucho.jsp.el;
31
32 import com.caucho.el.AbstractVariableResolver;
33 import com.caucho.jsp.PageContextImpl;
34
35 import javax.el.*;
36 import javax.servlet.jsp.el.ImplicitObjectELResolver  ;
37 import javax.servlet.jsp.el.ScopedAttributeELResolver ;
38 import java.beans.FeatureDescriptor ;
39 import java.util.ArrayList ;
40 import java.util.Iterator ;
41 import java.util.List ;
42 import java.util.Map ;
43
44
47 public class PageContextELResolver extends AbstractVariableResolver {
48 private final PageContextImpl _pageContext;
49
50 private final ELResolver []_customResolvers;
51
52 private final ImplicitObjectELResolver _implicitResolver
53 = new ImplicitObjectELResolver ();
54 private final ScopedAttributeELResolver _attrResolver
55 = new ScopedAttributeELResolver ();
56
57 private final MapELResolver _mapResolver = new MapELResolver();
58 private final ListELResolver _listResolver = new ListELResolver();
59 private final ArrayELResolver _arrayResolver = new ArrayELResolver();
60 private final ResourceBundleELResolver _bundleResolver
61 = new ResourceBundleELResolver();
62 private final BeanELResolver _beanResolver = new BeanELResolver();
63
64 public PageContextELResolver(PageContextImpl pageContext,
65 ELResolver []customResolvers)
66 {
67 _customResolvers = customResolvers;
68
69 _pageContext = pageContext;
70 }
71
72 public ELResolver []getCustomResolvers()
73 {
74 return _customResolvers;
75 }
76
77 @Override
78 public Class <?> getCommonPropertyType(ELContext env,
79 Object base)
80 {
81 Class common = null;
82
83 if (base == null)
84 common = String .class;
85
86 for (int i = 0; i < _customResolvers.length; i++) {
87 common = common(common,
88 _customResolvers[i].getCommonPropertyType(env, base));
89 }
90
91 common = common(common, _mapResolver.getCommonPropertyType(env, base));
92 common = common(common, _listResolver.getCommonPropertyType(env, base));
93 common = common(common, _arrayResolver.getCommonPropertyType(env, base));
94 common = common(common, _beanResolver.getCommonPropertyType(env, base));
95 common = common(common, _bundleResolver.getCommonPropertyType(env, base));
96
97 return common;
98 }
99
100 private static Class common(Class a, Class b)
101 {
102 if (a == null)
103 return b;
104 else if (b == null)
105 return a;
106 else if (a.isAssignableFrom(b))
107 return a;
108 else if (b.isAssignableFrom(a))
109 return b;
110 else return Object .class;
112 }
113
114 @Override
115 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext env,
116 Object base)
117 {
118 ArrayList <FeatureDescriptor > descriptors
119 = new ArrayList <FeatureDescriptor >();
120
121 for (int i = 0; i < _customResolvers.length; i++) {
122 addDescriptors(descriptors,
123 _customResolvers[i].getFeatureDescriptors(env, base));
124 }
125
126 addDescriptors(descriptors, _mapResolver.getFeatureDescriptors(env, base));
127 addDescriptors(descriptors,
128 _beanResolver.getFeatureDescriptors(env, base));
129 addDescriptors(descriptors,
130 _bundleResolver.getFeatureDescriptors(env, base));
131 addDescriptors(descriptors,
132 _implicitResolver.getFeatureDescriptors(env, base));
133 addDescriptors(descriptors,
134 _attrResolver.getFeatureDescriptors(env, base));
135
136 return descriptors.iterator();
137 }
138
139 private void addDescriptors(ArrayList <FeatureDescriptor > descriptors,
140 Iterator <FeatureDescriptor > iter)
141 {
142 if (iter == null)
143 return;
144
145 while (iter.hasNext()) {
146 FeatureDescriptor desc = iter.next();
147
148 descriptors.add(desc);
149 }
150 }
151
152 @Override
153 public Object getValue(ELContext env, Object base, Object property)
154 {
155 env.setPropertyResolved(false);
156
157 for (int i = 0; i < _customResolvers.length; i++) {
158 Object value = _customResolvers[i].getValue(env, base, property);
159
160 if (env.isPropertyResolved())
161 return value;
162 }
163
164 if (base != null) {
165 if (base instanceof Map )
166 return _mapResolver.getValue(env, base, property);
167 else if (base instanceof List )
168 return _listResolver.getValue(env, base, property);
169 else if (base.getClass().isArray())
170 return _arrayResolver.getValue(env, base, property);
171 else
172 return _beanResolver.getValue(env, base, property);
173 }
174 else if (property instanceof String ) {
175 env.setPropertyResolved(true);
176
177 return _pageContext.findAttribute(property.toString());
178 }
179 else
180 return null;
181 }
182
183 @Override
184 public boolean isReadOnly(ELContext env, Object base, Object property)
185 {
186 env.setPropertyResolved(false);
187
188 for (int i = 0; i < _customResolvers.length; i++) {
189 boolean value = _customResolvers[i].isReadOnly(env, base, property);
190
191 if (env.isPropertyResolved())
192 return value;
193 }
194
195 env.setPropertyResolved(true);
196
197 return false;
198 }
199
200 public void setValue(ELContext env,
201 Object base,
202 Object property,
203 Object value)
204 {
205 env.setPropertyResolved(false);
206
207 if (base != null) {
208 if (base instanceof Map )
209 _mapResolver.setValue(env, base, property, value);
210 else if (base instanceof List )
211 _listResolver.setValue(env, base, property, value);
212 else if (base.getClass().isArray())
213 _arrayResolver.setValue(env, base, property, value);
214 else
215 _beanResolver.setValue(env, base, property, value);
216 }
217 else if (property instanceof String ) {
218 env.setPropertyResolved(true);
219
220 _pageContext.setAttribute(property.toString(), value);
221 }
222 }
223 }
224 |
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