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1
28
29 package com.caucho.el;
30
31 import com.caucho.util.BeanUtil;
32 import com.caucho.vfs.WriteStream;
33
34 import javax.el.ELContext;
35 import javax.el.ELException;
36 import java.io.IOException  ;
37 import java.lang.reflect.Array ;
38 import java.lang.reflect.Method ;
39 import java.util.List ;
40 import java.util.Map ;
41
42
49 public class ArrayExpr extends Expr {
50 private Expr _left;
51 private Expr _right;
52
53 private Class _lastClass;
55 private String _lastField;
56 private Method _lastMethod;
57
58
64 public ArrayExpr(Expr left, Expr right)
65 {
66 _left = left;
67 _right = right;
68 }
69
70
73 public Expr getExpr()
74 {
75 return _left;
76 }
77
78
81 public Expr getIndex()
82 {
83 return _right;
84 }
85
86
89 @Override
90 public Expr createMethod(Expr []args)
91 {
92 if (! (_right instanceof StringLiteral))
93 return null;
94
95 StringLiteral literal = (StringLiteral) _right;
96
97 return new MethodExpr(_left, literal.getValue(), args);
98 }
99
100
107 @Override
108 public Object getValue(ELContext env)
109 throws ELException
110 {
111 Object aObj = _left.getValue(env);
112
113 if (aObj == null)
114 return null;
115
116 Object fieldObj = _right.getValue(env);
117 if (fieldObj == null)
118 return null;
119
120 if (aObj instanceof Map ) {
121 return ((Map ) aObj).get(fieldObj);
122 }
123
124 if (aObj instanceof List ) {
125 int ref = (int) toLong(fieldObj, null);
126
127 try {
128 List list = (List ) aObj;
129
130 if (ref < 0 || list.size() < ref)
131 return null;
132 else
133 return list.get(ref);
134 } catch (IndexOutOfBoundsException e) {
135 } catch (Exception e) {
136 return invocationError(e);
137 }
138 }
139
140 Class aClass = aObj.getClass();
141
142 if (aClass.isArray()) {
143 int ref = (int) toLong(fieldObj, null);
144
145 try {
146 return Array.get(aObj, ref);
147 } catch (IndexOutOfBoundsException e) {
148 } catch (Exception e) {
149 return error(e, env);
150 }
151 }
152
153 String fieldName = toString(fieldObj, env);
154
155 Method getMethod = null;
156 try {
157 synchronized (this) {
158 if (_lastClass == aClass && _lastField.equals(fieldName))
159 getMethod = _lastMethod;
160 else {
161 getMethod = BeanUtil.getGetMethod(aClass, fieldName);
164 _lastClass = aClass;
165 _lastField = fieldName;
166 _lastMethod = getMethod;
167 }
168 }
169
170 if (getMethod != null)
171 return getMethod.invoke(aObj, (Object []) null);
172 } catch (Exception e) {
173 return invocationError(e);
174 }
175
176 try {
177 getMethod = aClass.getMethod("get", new Class [] { String .class });
178
179 if (getMethod != null)
180 return getMethod.invoke(aObj, new Object [] {fieldName});
181 } catch (NoSuchMethodException e) {
182 return null;
183 } catch (Exception e) {
184 return invocationError(e);
185 }
186
187 try {
188 getMethod = aClass.getMethod("get", new Class [] { Object .class });
189
190 if (getMethod != null)
191 return getMethod.invoke(aObj, new Object [] {fieldObj});
192 } catch (Exception e) {
193 return invocationError(e);
194 }
195
196 ELException e = new ELException(L.l("no get method {0} for class {1}",
197 fieldName, aClass.getName()));
198
199 error(e, env);
200
201 return null;
202 }
203
204
209 @Override
210 public void printCreate(WriteStream os)
211 throws IOException
212 {
213 os.print("new com.caucho.el.ArrayExpr(");
214 _left.printCreate(os);
215 os.print(", ");
216 _right.printCreate(os);
217 os.print(")");
218 }
219
220
223 public boolean equals(Object o)
224 {
225 if (! (o instanceof ArrayExpr))
226 return false;
227
228 ArrayExpr expr = (ArrayExpr) o;
229
230 return (_left.equals(expr._left) && _right.equals(expr._right));
231 }
232
233
236 public String toString()
237 {
238 return _left + "[" + _right + "]";
239 }
240 }
241 |
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