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1
2
3 package org.apache.el.parser;
4
5 import java.lang.reflect.InvocationTargetException  ;
6 import java.lang.reflect.Method ;
7
8 import javax.el.ELException;
9 import javax.el.ELResolver;
10 import javax.el.MethodInfo;
11 import javax.el.PropertyNotFoundException;
12
13 import org.apache.el.lang.EvaluationContext;
14 import org.apache.el.util.MessageFactory;
15 import org.apache.el.util.ReflectionUtil;
16
17
18
22 public final class AstValue extends SimpleNode {
23
24 protected static class Target {
25 protected Object base;
26
27 protected Object property;
28 }
29
30 public AstValue(int id) {
31 super(id);
32 }
33
34 public Class getType(EvaluationContext ctx) throws ELException {
35 Target t = getTarget(ctx);
36 ctx.setPropertyResolved(false);
37 return ctx.getELResolver().getType(ctx, t.base, t.property);
38 }
39
40 private final Target getTarget(EvaluationContext ctx) throws ELException {
41 Object base = this.children[0].getValue(ctx);
43
44 if (base == null) {
46 throw new PropertyNotFoundException(MessageFactory.get(
47 "error.unreachable.base", this.children[0].getImage()));
48 }
49
50 Object property = null;
52 int propCount = this.jjtGetNumChildren() - 1;
53 int i = 1;
54
55 ELResolver resolver = ctx.getELResolver();
57 if (propCount > 1) {
58 while (base != null && i < propCount) {
59 property = this.children[i].getValue(ctx);
60 ctx.setPropertyResolved(false);
61 base = resolver.getValue(ctx, base, property);
62 i++;
63 }
64 if (base == null || property == null) {
67 throw new PropertyNotFoundException(MessageFactory.get(
68 "error.unreachable.property", property));
69 }
70 }
71
72 property = this.children[i].getValue(ctx);
73
74 if (property == null) {
75 throw new PropertyNotFoundException(MessageFactory.get(
76 "error.unreachable.property", this.children[i]));
77 }
78
79 Target t = new Target();
80 t.base = base;
81 t.property = property;
82 return t;
83 }
84
85 public Object getValue(EvaluationContext ctx) throws ELException {
86 Object base = this.children[0].getValue(ctx);
87 int propCount = this.jjtGetNumChildren();
88 int i = 1;
89 Object property = null;
90 ELResolver resolver = ctx.getELResolver();
91 while (base != null && i < propCount) {
92 property = this.children[i].getValue(ctx);
93 if (property == null) {
94 return null;
95 } else {
96 ctx.setPropertyResolved(false);
97 base = resolver.getValue(ctx, base, property);
98 }
99 i++;
100 }
101 return base;
102 }
103
104 public boolean isReadOnly(EvaluationContext ctx) throws ELException {
105 Target t = getTarget(ctx);
106 ctx.setPropertyResolved(false);
107 return ctx.getELResolver().isReadOnly(ctx, t.base, t.property);
108 }
109
110 public void setValue(EvaluationContext ctx, Object value)
111 throws ELException {
112 Target t = getTarget(ctx);
113 ctx.setPropertyResolved(false);
114 ctx.getELResolver().setValue(ctx, t.base, t.property, value);
115 }
116
117 public MethodInfo getMethodInfo(EvaluationContext ctx, Class [] paramTypes)
118 throws ELException {
119 Target t = getTarget(ctx);
120 Method m = ReflectionUtil.getMethod(t.base, t.property, paramTypes);
121 return new MethodInfo(m.getName(), m.getReturnType(), m
122 .getParameterTypes());
123 }
124
125 public Object invoke(EvaluationContext ctx, Class [] paramTypes,
126 Object [] paramValues) throws ELException {
127 Target t = getTarget(ctx);
128 Method m = ReflectionUtil.getMethod(t.base, t.property, paramTypes);
129 Object result = null;
130 try {
131 result = m.invoke(t.base, (Object []) paramValues);
132 } catch (IllegalAccessException iae) {
133 throw new ELException(iae);
134 } catch (InvocationTargetException ite) {
135 throw new ELException(ite.getCause());
136 }
137 return result;
138 }
139 }
140 |
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