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1
17
18 package javax.el;
19
20 import java.beans.FeatureDescriptor  ;
21 import java.lang.reflect.Array ;
22 import java.util.Arrays ;
23 import java.util.Iterator ;
24
25 public class ArrayELResolver extends ELResolver {
26
27 private final boolean readOnly;
28
29 public ArrayELResolver() {
30 this.readOnly = false;
31 }
32
33 public ArrayELResolver(boolean readOnly) {
34 this.readOnly = readOnly;
35 }
36
37 public Object getValue(ELContext context, Object base, Object property)
38 throws NullPointerException , PropertyNotFoundException, ELException {
39 if (context == null) {
40 throw new NullPointerException ();
41 }
42
43 if (base != null && base.getClass().isArray()) {
44 context.setPropertyResolved(true);
45 int idx = coerce(property);
46 if (idx < 0 || idx >= Array.getLength(base)) {
47 return null;
48 } else {
49 return Array.get(base, idx);
50 }
51 }
52
53 return null;
54 }
55
56 public Class <?> getType(ELContext context, Object base, Object property)
57 throws NullPointerException , PropertyNotFoundException, ELException {
58 if (context == null) {
59 throw new NullPointerException ();
60 }
61
62 if (base != null && base.getClass().isArray()) {
63 context.setPropertyResolved(true);
64 int idx = coerce(property);
65 checkBounds(base, idx);
66 return base.getClass().getComponentType();
67 }
68
69 return null;
70 }
71
72 public void setValue(ELContext context, Object base, Object property,
73 Object value) throws NullPointerException ,
74 PropertyNotFoundException, PropertyNotWritableException,
75 ELException {
76 if (context == null) {
77 throw new NullPointerException ();
78 }
79
80 if (base != null && base.getClass().isArray()) {
81 context.setPropertyResolved(true);
82
83 if (this.readOnly) {
84 throw new PropertyNotWritableException(message(context,
85 "resolverNotWriteable", new Object [] { base.getClass()
86 .getName() }));
87 }
88
89 int idx = coerce(property);
90 checkBounds(base, idx);
91 Array.set(base, idx, value);
92 }
93 }
94
95 public boolean isReadOnly(ELContext context, Object base, Object property)
96 throws NullPointerException , PropertyNotFoundException, ELException {
97 if (context == null) {
98 throw new NullPointerException ();
99 }
100
101 if (base != null && base.getClass().isArray()) {
102 context.setPropertyResolved(true);
103 int idx = coerce(property);
104 checkBounds(base, idx);
105 }
106
107 return this.readOnly;
108 }
109
110 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext context, Object base) {
111 if (base != null && base.getClass().isArray()) {
112 FeatureDescriptor [] descs = new FeatureDescriptor [Array.getLength(base)];
113 for (int i = 0; i < descs.length; i++) {
114 descs[i] = new FeatureDescriptor ();
115 descs[i].setDisplayName("["+i+"]");
116 descs[i].setExpert(false);
117 descs[i].setHidden(false);
118 descs[i].setName(""+i);
119 descs[i].setPreferred(true);
120 descs[i].setValue(RESOLVABLE_AT_DESIGN_TIME, Boolean.FALSE);
121 descs[i].setValue(TYPE, Integer .class);
122 }
123 return Arrays.asList(descs).iterator();
124 }
125 return null;
126 }
127
128 public Class <?> getCommonPropertyType(ELContext context, Object base) {
129 if (base != null && base.getClass().isArray()) {
130 return Integer .class;
131 }
132 return null;
133 }
134
135 private final static void checkBounds(Object base, int idx) {
136 if (idx < 0 || idx >= Array.getLength(base)) {
137 throw new PropertyNotFoundException(
138 new ArrayIndexOutOfBoundsException (idx).getMessage());
139 }
140 }
141
142 private final static int coerce(Object property) {
143 if (property instanceof Number ) {
144 return ((Number ) property).intValue();
145 }
146 if (property instanceof Character ) {
147 return ((Character ) property).charValue();
148 }
149 if (property instanceof Boolean ) {
150 return (((Boolean ) property).booleanValue() ? 1 : 0);
151 }
152 if (property instanceof String ) {
153 return Integer.parseInt((String ) property);
154 }
155 throw new IllegalArgumentException (property != null ? property
156 .toString() : "null");
157 }
158
159 }
160 |
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