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1
11
12 package org.eclipse.jface.internal.databinding.internal.beans;
13
14 import java.beans.PropertyChangeListener  ;
15 import java.beans.PropertyDescriptor ;
16 import java.lang.reflect.InvocationTargetException ;
17 import java.lang.reflect.Method ;
18 import java.util.Arrays ;
19 import java.util.Collection ;
20 import java.util.HashSet ;
21 import java.util.Set ;
22
23 import org.eclipse.jface.internal.databinding.provisional.observable.Diffs;
24 import org.eclipse.jface.internal.databinding.provisional.observable.set.ObservableSet;
25 import org.eclipse.jface.util.Assert;
26
27
31 public class JavaBeanObservableSet extends ObservableSet {
32
33 private final Object object;
34
35 private PropertyChangeListener collectionListener = new PropertyChangeListener () {
36 public void propertyChange(java.beans.PropertyChangeEvent event) {
37 if (!updating) {
38 if (JavaBeanObservableSet.this.descriptor.getName().equals(
39 event.getPropertyName())) {
40 Set newElements = new HashSet (Arrays.asList(getValues()));
41 Set addedElements = new HashSet (newElements);
42 Set removedElements = new HashSet (wrappedSet);
43 removedElements.removeAll(newElements);
46 addedElements.removeAll(wrappedSet);
47 wrappedSet = newElements;
48 fireSetChange(Diffs.createSetDiff(addedElements,
49 removedElements));
50 }
51 }
52 }
53 };
54
55 private boolean updating = false;
56
57 private PropertyDescriptor descriptor;
58
59 private ListenerSupport collectionListenSupport = new ListenerSupport(
60 collectionListener);
61
62
67 public JavaBeanObservableSet(Object object, PropertyDescriptor descriptor,
68 Class elementType) {
69 super(new HashSet (), descriptor.getPropertyType());
70 this.object = object;
71 this.descriptor = descriptor;
72 wrappedSet.addAll(Arrays.asList(getValues()));
73 }
74
75 protected void firstListenerAdded() {
76 collectionListenSupport.hookListener(this.object);
77 }
78
79 protected void lastListenerRemoved() {
80 if (collectionListenSupport != null) {
81 collectionListenSupport.dispose();
82 }
83 }
84
85 private Object primGetValues() {
86 try {
87 Method readMethod = descriptor.getReadMethod();
88 if (!readMethod.isAccessible()) {
89 readMethod.setAccessible(true);
90 }
91 return readMethod.invoke(object, new Object [0]);
92 } catch (IllegalArgumentException e) {
93 } catch (IllegalAccessException e) {
94 } catch (InvocationTargetException e) {
95 }
96 Assert.isTrue(false, "Could not read collection values"); return null;
98 }
99
100 private Object [] getValues() {
101 Object [] values = null;
102
103 Object result = primGetValues();
104 if (descriptor.getPropertyType().isArray())
105 values = (Object []) result;
106 else {
107 Collection list = (Collection ) result;
109 if (list != null) {
110 values = list.toArray();
111 } else {
112 values = new Object [] {};
113 }
114 }
115 return values;
116 }
117
118 }
119 |
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