|
1
11
12 package org.eclipse.jface.internal.databinding.provisional.observable.mapping;
13
14 import java.util.Collections  ;
15 import java.util.HashMap ;
16 import java.util.HashSet ;
17 import java.util.Iterator ;
18 import java.util.Map ;
19 import java.util.Set ;
20
21 import org.eclipse.jface.internal.databinding.provisional.observable.IObservable;
22 import org.eclipse.jface.internal.databinding.provisional.observable.set.IObservableSet;
23 import org.eclipse.jface.internal.databinding.provisional.observable.set.ISetChangeListener;
24 import org.eclipse.jface.internal.databinding.provisional.observable.set.SetDiff;
25 import org.eclipse.jface.internal.databinding.provisional.observable.set.WritableSet;
26
27
31 public class BidirectionalMapping extends AbstractObservableMapping implements
32 IBidirectionalMapping, IObservableMappingWithDomain {
33
34 private final IObservableMapping wrappedMapping;
35
36 private IObservableSet range;
37
38 private Map valueToElements = new HashMap ();
39
40 private ISetChangeListener domainListener = new ISetChangeListener() {
41 public void handleSetChange(IObservableSet source, SetDiff diff) {
42 Set rangeAdditions = new HashSet ();
43 for (Iterator it = diff.getAdditions().iterator(); it.hasNext();) {
44 Object added = it.next();
45 Object mappingValue = wrappedMapping.getMappingValue(added);
46 rangeAdditions.add(mappingValue);
47 addMapping(mappingValue, added);
48 }
49 range.addAll(rangeAdditions);
50 for (Iterator it = diff.getRemovals().iterator(); it.hasNext();) {
51 Object removed = it.next();
52 removeMapping(wrappedMapping.getMappingValue(removed), removed);
53 }
54 range.retainAll(valueToElements.keySet());
55 }
56 };
57
58 private IMappingChangeListener mappingChangeListener = new IMappingChangeListener() {
59 public void handleMappingValueChange(IObservable source,
60 MappingDiff diff) {
61 Set affectedElements = diff.getElements();
62 for (Iterator it = affectedElements.iterator(); it.hasNext();) {
63 Object element = it.next();
64 Object oldFunctionValue = diff.getOldMappingValues(element,
65 new int[0])[0];
66 Object newFunctionValue = diff.getNewMappingValues(element,
67 new int[0])[0];
68 removeMapping(oldFunctionValue, element);
69 addMapping(newFunctionValue, element);
70 }
71 Set tempRange = valueToElements.keySet();
72 range.addAll(tempRange);
73 range.retainAll(tempRange);
74 fireMappingValueChange(diff);
75 }
76 };
77
78 private IObservableSet domain;
79
80
83 public BidirectionalMapping(IObservableMappingWithDomain functionWithDomain) {
84 this(functionWithDomain, functionWithDomain.getDomain());
85 }
86
87
91 public BidirectionalMapping(IObservableMapping wrappedMapping,
92 IObservableSet domain) {
93 this.wrappedMapping = wrappedMapping;
94 this.domain = domain;
95 Set tempRange = new HashSet ();
96 for (Iterator it = domain.iterator(); it.hasNext();) {
97 Object element = it.next();
98 Object functionValue = wrappedMapping.getMappingValue(element);
99 addMapping(functionValue, element);
100 tempRange.add(functionValue);
101 }
102 this.range = new WritableSet(tempRange);
103 domain.addSetChangeListener(domainListener);
104 }
105
106
111 private void addMapping(Object functionValue, Object element) {
112 Object elementOrSet = valueToElements.get(functionValue);
113 if (elementOrSet == null) {
114 valueToElements.put(functionValue, element);
115 return;
116 }
117 if (!(elementOrSet instanceof Set )) {
118 elementOrSet = new HashSet (Collections.singleton(elementOrSet));
119 valueToElements.put(functionValue, elementOrSet);
120 }
121 Set set = (Set ) elementOrSet;
122 set.add(element);
123 }
124
125
130 private void removeMapping(Object functionValue, Object element) {
131 Object elementOrSet = valueToElements.get(functionValue);
132 if (elementOrSet instanceof Set ) {
133 Set set = (Set ) elementOrSet;
134 set.remove(element);
135 if (set.size() == 0) {
136 valueToElements.remove(functionValue);
137 }
138 } else {
139 valueToElements.remove(functionValue);
140 }
141 }
142
143 protected Object doGetMappingValue(Object element) {
144 return wrappedMapping.getMappingValue(element);
145 }
146
147 public void setMappingValue(Object element, Object value) {
148 wrappedMapping.setMappingValue(element, value);
149 }
150
151 public IObservableSet getRange() {
152 return range;
153 }
154
155 public Set getDomainElementsForValue(Object value) {
156 return null;
157 }
158
159 public void dispose() {
160 wrappedMapping.removeMappingChangeListener(mappingChangeListener);
161 domain.removeSetChangeListener(domainListener);
162 }
163
164 public IObservableSet getDomain() {
165 return domain;
166 }
167
168 public Object getValueType() {
169 return wrappedMapping.getValueType();
170 }
171
172 }
173 |
Popular Tags |
Java API By Example, From Geeks To Geeks.