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1
17
18 package javax.el;
19
20 import java.beans.FeatureDescriptor  ;
21 import java.util.Iterator ;
22
23 public class CompositeELResolver extends ELResolver {
24
25 private int size;
26
27 private ELResolver[] resolvers;
28
29 public CompositeELResolver() {
30 this.size = 0;
31 this.resolvers = new ELResolver[2];
32 }
33
34 public void add(ELResolver elResolver) {
35 if (elResolver == null) {
36 throw new NullPointerException ();
37 }
38
39 if (this.size >= this.resolvers.length) {
40 ELResolver[] nr = new ELResolver[this.size * 2];
41 System.arraycopy(this.resolvers, 0, nr, 0, this.size);
42 this.resolvers = nr;
43 }
44 this.resolvers[this.size++] = elResolver;
45 }
46
47 public Object getValue(ELContext context, Object base, Object property)
48 throws NullPointerException , PropertyNotFoundException, ELException {
49 context.setPropertyResolved(false);
50 int sz = this.size;
51 Object result = null;
52 for (int i = 0; i < sz; i++) {
53 result = this.resolvers[i].getValue(context, base, property);
54 if (context.isPropertyResolved()) {
55 return result;
56 }
57 }
58 return null;
59 }
60
61 public void setValue(ELContext context, Object base, Object property,
62 Object value) throws NullPointerException ,
63 PropertyNotFoundException, PropertyNotWritableException,
64 ELException {
65 context.setPropertyResolved(false);
66 int sz = this.size;
67 for (int i = 0; i < sz; i++) {
68 this.resolvers[i].setValue(context, base, property, value);
69 if (context.isPropertyResolved()) {
70 return;
71 }
72 }
73 }
74
75 public boolean isReadOnly(ELContext context, Object base, Object property)
76 throws NullPointerException , PropertyNotFoundException, ELException {
77 context.setPropertyResolved(false);
78 int sz = this.size;
79 boolean readOnly = false;
80 for (int i = 0; i < sz; i++) {
81 readOnly = this.resolvers[i].isReadOnly(context, base, property);
82 if (context.isPropertyResolved()) {
83 return readOnly;
84 }
85 }
86 return false;
87 }
88
89 public Iterator <FeatureDescriptor > getFeatureDescriptors(ELContext context, Object base) {
90 return new FeatureIterator(context, base, this.resolvers, this.size);
91 }
92
93 public Class <?> getCommonPropertyType(ELContext context, Object base) {
94 int sz = this.size;
95 Class <?> commonType = null, type = null;
96 for (int i = 0; i < sz; i++) {
97 type = this.resolvers[i].getCommonPropertyType(context, base);
98 if (type != null
99 && (commonType == null || commonType.isAssignableFrom(type))) {
100 commonType = type;
101 }
102 }
103 return commonType;
104 }
105
106 public Class <?> getType(ELContext context, Object base, Object property)
107 throws NullPointerException , PropertyNotFoundException, ELException {
108 context.setPropertyResolved(false);
109 int sz = this.size;
110 Class <?> type;
111 for (int i = 0; i < sz; i++) {
112 type = this.resolvers[i].getType(context, base, property);
113 if (context.isPropertyResolved()) {
114 return type;
115 }
116 }
117 return null;
118 }
119
120 private final static class FeatureIterator implements Iterator <FeatureDescriptor > {
121
122 private final ELContext context;
123
124 private final Object base;
125
126 private final ELResolver[] resolvers;
127
128 private final int size;
129
130 private Iterator itr;
131
132 private int idx;
133
134 public FeatureIterator(ELContext context, Object base,
135 ELResolver[] resolvers, int size) {
136 this.context = context;
137 this.base = base;
138 this.resolvers = resolvers;
139 this.size = size;
140
141 this.idx = 0;
142 this.guaranteeIterator();
143 }
144
145 private void guaranteeIterator() {
146 while (this.itr == null && this.idx < this.size) {
147 this.itr = this.resolvers[this.idx].getFeatureDescriptors(
148 this.context, this.base);
149 this.idx++;
150 }
151 }
152
153 public boolean hasNext() {
154 return this.itr != null;
155 }
156
157 public FeatureDescriptor next() {
158 Object result = null;
159 if (this.itr != null) {
160 if (this.itr.hasNext()) {
161 result = this.itr.next();
162 if (!this.itr.hasNext()) {
163 this.itr = null;
164 this.guaranteeIterator();
165 }
166 }
167 }
168 return (FeatureDescriptor ) result;
169 }
170
171 public void remove() {
172 throw new UnsupportedOperationException ();
173 }
174 }
175
176 }
177 |
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