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1
25
26 package org.apache.jasper.runtime;
27
28 import java.util.Iterator  ;
29
30 import javax.el.ELContext;
31 import javax.el.ELResolver;
32 import javax.el.ValueExpression;
33 import javax.el.ExpressionFactory;
34
35 import javax.servlet.jsp.PageContext ;
36 import javax.servlet.jsp.el.Expression ;
37 import javax.servlet.jsp.el.ELException ;
38 import javax.servlet.jsp.el.FunctionMapper ;
39 import javax.servlet.jsp.el.ExpressionEvaluator ;
40 import javax.servlet.jsp.el.VariableResolver ;
41
42
49
50 public class ExpressionEvaluatorImpl extends ExpressionEvaluator
51 {
52 private PageContext pageContext;
53
54
58 public ExpressionEvaluatorImpl (PageContext pageContext) {
59 this.pageContext = pageContext;
60 }
61
62 public Expression parseExpression(String expression,
64 Class expectedType,
65 FunctionMapper fMapper )
66 throws ELException {
67
68 ExpressionFactory fac = JspApplicationContextImpl.expressionFactory;
69 javax.el.ValueExpression expr;
70 ELContextImpl elContext = new ELContextImpl(null);
71 javax.el.FunctionMapper fm = new FunctionMapperWrapper(fMapper);
72 elContext.setFunctionMapper(fm);
73 try {
74 expr = fac.createValueExpression(
75 elContext,
76 expression, expectedType);
77 } catch (javax.el.ELException ex) {
78 throw new ELException (ex);
79 }
80 return new ExpressionImpl(expr, pageContext);
81 }
82
83 public Object evaluate(String expression,
84 Class expectedType,
85 VariableResolver vResolver,
86 FunctionMapper fMapper )
87 throws ELException {
88
89 ELContextImpl elContext;
90 if (vResolver instanceof VariableResolverImpl) {
91 elContext = (ELContextImpl) pageContext.getELContext();
92 }
93 else {
94 elContext = new ELContextImpl(new ELResolverWrapper(vResolver));
97 }
98
99 javax.el.FunctionMapper fm = new FunctionMapperWrapper(fMapper);
100 elContext.setFunctionMapper(fm);
101 ExpressionFactory fac = JspApplicationContextImpl.expressionFactory;
102 Object value;
103 try {
104 ValueExpression expr = fac.createValueExpression(
105 elContext,
106 expression,
107 expectedType);
108 value = expr.getValue(elContext);
109 } catch (javax.el.ELException ex) {
110 throw new ELException (ex);
111 }
112 return value;
113 }
114
115 static private class ExpressionImpl extends Expression {
116
117 private ValueExpression valueExpr;
118 private PageContext pageContext;
119
120 ExpressionImpl(ValueExpression valueExpr,
121 PageContext pageContext) {
122 this.valueExpr = valueExpr;
123 this.pageContext = pageContext;
124 }
125
126 public Object evaluate(VariableResolver vResolver) throws ELException {
127
128 ELContext elContext;
129 if (vResolver instanceof VariableResolverImpl) {
130 elContext = pageContext.getELContext();
131 }
132 else {
133 elContext = new ELContextImpl(new ELResolverWrapper(vResolver));
136 }
137 try {
138 return valueExpr.getValue(elContext);
139 } catch (javax.el.ELException ex) {
140 throw new ELException (ex);
141 }
142 }
143 }
144
145 private static class FunctionMapperWrapper
146 extends javax.el.FunctionMapper {
147
148 private FunctionMapper mapper;
149
150 FunctionMapperWrapper(FunctionMapper mapper) {
151 this.mapper = mapper;
152 }
153
154 public java.lang.reflect.Method resolveFunction(String prefix,
155 String localName) {
156 return mapper.resolveFunction(prefix, localName);
157 }
158 }
159
160 private static class ELResolverWrapper extends ELResolver {
161 private VariableResolver vResolver;
162
163 ELResolverWrapper(VariableResolver vResolver) {
164 this.vResolver = vResolver;
165 }
166
167 public Object getValue(ELContext context,
168 Object base,
169 Object property)
170 throws javax.el.ELException {
171 if (base == null) {
172 context.setPropertyResolved(true);
173 try {
174 return vResolver.resolveVariable(property.toString());
175 } catch (ELException ex) {
176 throw new javax.el.ELException(ex);
177 }
178 }
179 return null;
180 }
181
182 public Class getType(ELContext context,
183 Object base,
184 Object property)
185 throws javax.el.ELException {
186 return null;
187 }
188
189 public void setValue(ELContext context,
190 Object base,
191 Object property,
192 Object value)
193 throws javax.el.ELException {
194 }
195
196 public boolean isReadOnly(ELContext context,
197 Object base,
198 Object property)
199 throws javax.el.ELException {
200 return false;
201 }
202
203 public Iterator getFeatureDescriptors(ELContext context,
204 Object base) {
205 return null;
206 }
207
208 public Class getCommonPropertyType(ELContext context,
209 Object base) {
210 return null;
211 }
212 }
213 }
214 |
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