|
1
17
18 package javax.el;
19
20 import java.beans.FeatureDescriptor  ;
21 import java.util.ArrayList ;
22 import java.util.Collections ;
23 import java.util.HashMap ;
24 import java.util.Iterator ;
25 import java.util.List ;
26 import java.util.Map ;
27
28 public class MapELResolver extends ELResolver {
29
30 private final static Class UNMODIFIABLE = Collections.unmodifiableMap(
31 new HashMap ()).getClass();
32
33 private final boolean readOnly;
34
35 public MapELResolver() {
36 this.readOnly = false;
37 }
38
39 public MapELResolver(boolean readOnly) {
40 this.readOnly = readOnly;
41 }
42
43 public Object getValue(ELContext context, Object base, Object property)
44 throws NullPointerException , PropertyNotFoundException, ELException {
45 if (context == null) {
46 throw new NullPointerException ();
47 }
48
49 if (base instanceof Map ) {
50 context.setPropertyResolved(true);
51 return ((Map ) base).get(property);
52 }
53
54 return null;
55 }
56
57 public Class <?> getType(ELContext context, Object base, Object property)
58 throws NullPointerException , PropertyNotFoundException, ELException {
59 if (context == null) {
60 throw new NullPointerException ();
61 }
62
63 if (base instanceof Map ) {
64 context.setPropertyResolved(true);
65 Object obj = ((Map ) base).get(property);
66 return (obj != null) ? obj.getClass() : null;
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 instanceof Map ) {
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 try {
90 ((Map ) base).put(property, value);
91 } catch (UnsupportedOperationException e) {
92 throw new PropertyNotWritableException(e);
93 }
94 }
95 }
96
97 public boolean isReadOnly(ELContext context, Object base, Object property)
98 throws NullPointerException , PropertyNotFoundException, ELException {
99 if (context == null) {
100 throw new NullPointerException ();
101 }
102
103 if (base instanceof Map ) {
104 context.setPropertyResolved(true);
105 return this.readOnly || UNMODIFIABLE.equals(base.getClass());
106 }
107
108 return this.readOnly;
109 }
110
111 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext context, Object base) {
112 if (base instanceof Map ) {
113 Iterator itr = ((Map ) base).keySet().iterator();
114 List <FeatureDescriptor > feats = new ArrayList <FeatureDescriptor >();
115 Object key;
116 FeatureDescriptor desc;
117 while (itr.hasNext()) {
118 key = itr.next();
119 desc = new FeatureDescriptor ();
120 desc.setDisplayName(key.toString());
121 desc.setExpert(false);
122 desc.setHidden(false);
123 desc.setName(key.toString());
124 desc.setPreferred(true);
125 desc.setValue(RESOLVABLE_AT_DESIGN_TIME, Boolean.FALSE);
126 desc.setValue(TYPE, key.getClass());
127 feats.add(desc);
128 }
129 return feats.iterator();
130 }
131 return null;
132 }
133
134 public Class <?> getCommonPropertyType(ELContext context, Object base) {
135 if (base instanceof Map ) {
136 return Object .class;
137 }
138 return null;
139 }
140
141 }
142 |
Popular Tags |
Java API By Example, From Geeks To Geeks.