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1
23
24 package com.sun.el.parser;
25
26 import java.lang.reflect.InvocationTargetException  ;
27 import java.lang.reflect.Method ;
28
29 import javax.el.ELException;
30 import javax.el.ELResolver;
31 import javax.el.MethodInfo;
32 import javax.el.PropertyNotFoundException;
33
34 import com.sun.el.lang.EvaluationContext;
35 import com.sun.el.util.MessageFactory;
36 import com.sun.el.util.ReflectionUtil;
37
38
42 public final class AstValue extends SimpleNode {
43
44 protected static class Target {
45 protected Object base;
46
47 protected Object property;
48 }
49
50 public AstValue(int id) {
51 super(id);
52 }
53
54 public Class getType(EvaluationContext ctx) throws ELException {
55 Target t = getTarget(ctx);
56 ctx.setPropertyResolved(false);
57 return ctx.getELResolver().getType(ctx, t.base, t.property);
58 }
59
60 private final Target getTarget(EvaluationContext ctx) throws ELException {
61 Object base = this.children[0].getValue(ctx);
63
64 if (base == null) {
66 throw new PropertyNotFoundException(MessageFactory.get(
67 "error.unreachable.base", this.children[0].getImage()));
68 }
69
70 Object property = null;
72 int propCount = this.jjtGetNumChildren() - 1;
73 int i = 1;
74
75 ELResolver resolver = ctx.getELResolver();
77 if (propCount > 1) {
78 while (base != null && i < propCount) {
79 property = this.children[i].getValue(ctx);
80 ctx.setPropertyResolved(false);
81 base = resolver.getValue(ctx, base, property);
82 i++;
83 }
84 if (base == null || property == null) {
87 throw new PropertyNotFoundException(MessageFactory.get(
88 "error.unreachable.property", property));
89 }
90 }
91
92 property = this.children[i].getValue(ctx);
93
94 if (property == null) {
95 throw new PropertyNotFoundException(MessageFactory.get(
96 "error.unreachable.property", this.children[i]));
97 }
98
99 Target t = new Target();
100 t.base = base;
101 t.property = property;
102 return t;
103 }
104
105 public Object getValue(EvaluationContext ctx) throws ELException {
106 Object base = this.children[0].getValue(ctx);
107 int propCount = this.jjtGetNumChildren();
108 int i = 1;
109 Object property = null;
110 ELResolver resolver = ctx.getELResolver();
111 while (base != null && i < propCount) {
112 property = this.children[i].getValue(ctx);
113 if (property == null) {
114 return null;
115 } else {
116 ctx.setPropertyResolved(false);
117 base = resolver.getValue(ctx, base, property);
118 }
119 i++;
120 }
121 return base;
122 }
123
124 public boolean isReadOnly(EvaluationContext ctx) throws ELException {
125 Target t = getTarget(ctx);
126 ctx.setPropertyResolved(false);
127 return ctx.getELResolver().isReadOnly(ctx, t.base, t.property);
128 }
129
130 public void setValue(EvaluationContext ctx, Object value)
131 throws ELException {
132 Target t = getTarget(ctx);
133 ctx.setPropertyResolved(false);
134 ctx.getELResolver().setValue(ctx, t.base, t.property, value);
135 }
136
137 public MethodInfo getMethodInfo(EvaluationContext ctx, Class [] paramTypes)
138 throws ELException {
139 Target t = getTarget(ctx);
140 Method m = ReflectionUtil.getMethod(t.base, t.property, paramTypes);
141 return new MethodInfo(m.getName(), m.getReturnType(), m
142 .getParameterTypes());
143 }
144
145 public Object invoke(EvaluationContext ctx, Class [] paramTypes,
146 Object [] paramValues) throws ELException {
147 Target t = getTarget(ctx);
148 Method m = ReflectionUtil.getMethod(t.base, t.property, paramTypes);
149 Object result = null;
150 try {
151 result = m.invoke(t.base, (Object []) paramValues);
152 } catch (IllegalAccessException iae) {
153 throw new ELException(iae);
154 } catch (InvocationTargetException ite) {
155 throw new ELException(ite.getCause());
156 }
157 return result;
158 }
159 }
160 |
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