Source code: ognl/ArrayPropertyAccessor.java
1 //--------------------------------------------------------------------------
2 // Copyright (c) 1998-2004, Drew Davidson and Luke Blanshard
3 // All rights reserved.
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
7 // met:
8 //
9 // Redistributions of source code must retain the above copyright notice,
10 // this list of conditions and the following disclaimer.
11 // Redistributions in binary form must reproduce the above copyright
12 // notice, this list of conditions and the following disclaimer in the
13 // documentation and/or other materials provided with the distribution.
14 // Neither the name of the Drew Davidson nor the names of its contributors
15 // may be used to endorse or promote products derived from this software
16 // without specific prior written permission.
17 //
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 // FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 // COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23 // INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
24 // BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
25 // OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26 // AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
28 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
29 // DAMAGE.
30 //--------------------------------------------------------------------------
31 package ognl;
32
33 import java.lang.reflect.Array;
34 import java.util.Map;
35
36 /**
37 * Implementation of PropertyAccessor that uses numbers and dynamic subscripts as
38 * properties to index into Java arrays.
39 * @author Luke Blanshard (blanshlu@netscape.net)
40 * @author Drew Davidson (drew@ognl.org)
41 */
42 public class ArrayPropertyAccessor extends ObjectPropertyAccessor
43 implements PropertyAccessor // This is here to make javadoc show this class as an implementor
44 {
45 public Object getProperty( Map context, Object target, Object name ) throws OgnlException
46 {
47 Object result = null;
48
49 if (name instanceof String) {
50 if (name.equals("length")) {
51 result = new Integer( Array.getLength(target) );
52 } else {
53 result = super.getProperty( context, target, name );
54 }
55 } else {
56 Object index = name;
57
58 if (index instanceof DynamicSubscript) {
59 int len = Array.getLength(target);
60
61 switch (((DynamicSubscript)index).getFlag()) {
62 case DynamicSubscript.ALL:
63 result = Array.newInstance( target.getClass().getComponentType(), len );
64 System.arraycopy( target, 0, result, 0, len );
65 break;
66 case DynamicSubscript.FIRST:
67 index = new Integer((len > 0) ? 0 : -1);
68 break;
69 case DynamicSubscript.MID:
70 index = new Integer((len > 0) ? (len / 2) : -1);
71 break;
72 case DynamicSubscript.LAST:
73 index = new Integer((len > 0) ? (len - 1) : -1);
74 break;
75 }
76 }
77 if (result == null) {
78 if (index instanceof Number) {
79 int i = ((Number)index).intValue();
80
81 result = (i >= 0) ? Array.get(target, i) : null;
82 } else {
83 throw new NoSuchPropertyException(target, index);
84 }
85 }
86 }
87 return result;
88 }
89
90 public void setProperty( Map context, Object target, Object name, Object value ) throws OgnlException
91 {
92 Object index = name;
93 boolean isNumber = (index instanceof Number);
94
95 if (isNumber || (index instanceof DynamicSubscript)) {
96 TypeConverter converter = ((OgnlContext)context).getTypeConverter();
97 Object convertedValue;
98
99 convertedValue = converter.convertValue(context, target, null, name.toString(), value, target.getClass().getComponentType());
100 if (isNumber) {
101 int i = ((Number)index).intValue();
102
103 if (i >= 0) {
104 Array.set(target, i, convertedValue);
105 }
106 } else {
107 int len = Array.getLength(target);
108
109 switch ( ((DynamicSubscript)index).getFlag() ) {
110 case DynamicSubscript.ALL:
111 System.arraycopy(target, 0, convertedValue, 0, len);
112 return;
113 case DynamicSubscript.FIRST:
114 index = new Integer((len > 0) ? 0 : -1);
115 break;
116 case DynamicSubscript.MID:
117 index = new Integer((len > 0) ? (len / 2) : -1);
118 break;
119 case DynamicSubscript.LAST:
120 index = new Integer((len > 0 ) ? (len - 1) : -1);
121 break;
122 }
123 }
124 } else {
125 if (name instanceof String) {
126 super.setProperty(context, target, name, value);
127 } else {
128 throw new NoSuchPropertyException(target, index);
129 }
130 }
131 }
132 }