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1
11 package org.eclipse.ui.internal.texteditor;
12
13 import java.util.HashMap  ;
14 import java.util.Iterator ;
15 import java.util.LinkedHashSet ;
16 import java.util.Map ;
17 import java.util.Set ;
18
19 import org.eclipse.core.runtime.Assert;
20
21 import org.eclipse.jface.preference.IPreferenceStore;
22 import org.eclipse.jface.util.IPropertyChangeListener;
23 import org.eclipse.jface.util.PropertyChangeEvent;
24
25 public final class PropertyEventDispatcher {
26 private final Map fHandlerMap= new HashMap ();
27 private final Map fReverseMap= new HashMap ();
28 private final IPreferenceStore fStore;
29 private final IPropertyChangeListener fListener= new IPropertyChangeListener() {
30 public void propertyChange(PropertyChangeEvent event) {
31 firePropertyChange(event);
32 }
33 };
34 public PropertyEventDispatcher(IPreferenceStore store) {
35 Assert.isLegal(store != null);
36 fStore= store;
37 }
38 public void dispose() {
39 if (!fReverseMap.isEmpty())
40 fStore.removePropertyChangeListener(fListener);
41 fReverseMap.clear();
42 fHandlerMap.clear();
43 }
44 private void firePropertyChange(PropertyChangeEvent event) {
45 Object value= fHandlerMap.get(event.getProperty());
46 if (value instanceof IPropertyChangeListener)
47 ((IPropertyChangeListener) value).propertyChange(event);
48 else if (value instanceof Set )
49 for (Iterator it= ((Set ) value).iterator(); it.hasNext(); )
50 ((IPropertyChangeListener) it.next()).propertyChange(event);
51 }
52 public void addPropertyChangeListener(String property, IPropertyChangeListener listener) {
53 Assert.isLegal(property != null);
54 Assert.isLegal(listener != null);
55
56 if (fReverseMap.isEmpty())
57 fStore.addPropertyChangeListener(fListener);
58
59 multiMapPut(fHandlerMap, property, listener);
60 multiMapPut(fReverseMap, listener, property);
61 }
62 private void multiMapPut(Map map, Object key, Object value) {
63 Object mapping= map.get(key);
64 if (mapping == null) {
65 map.put(key, value);
66 } else if (mapping instanceof Set ) {
67 ((Set ) mapping).add(value);
68 } else {
69 Set set= new LinkedHashSet ();
70 set.add(mapping);
71 set.add(value);
72 map.put(key, set);
73 }
74 }
75 private void multiMapRemove(Map map, Object key, Object value) {
76 Object mapping= map.get(key);
77 if (mapping instanceof Set ) {
78 ((Set ) mapping).remove(value);
79 } else if (mapping != null) {
80 map.remove(key);
81 }
82 }
83 public void removePropertyChangeListener(IPropertyChangeListener listener) {
84 Object value= fReverseMap.get(listener);
85 if (value == null)
86 return;
87 if (value instanceof String ) {
88 fReverseMap.remove(listener);
89 multiMapRemove(fHandlerMap, value, listener);
90 } else if (value instanceof Set ) {
91 fReverseMap.remove(listener);
92 for (Iterator it= ((Set ) value).iterator(); it.hasNext();)
93 multiMapRemove(fHandlerMap, it.next(), listener);
94 }
95
96 if (fReverseMap.isEmpty())
97 fStore.removePropertyChangeListener(fListener);
98 }
99 } |
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