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13 package org.eclipse.core.internal.databinding.internal.beans;
14
15 import java.beans.PropertyChangeListener  ;
16 import java.beans.PropertyDescriptor ;
17 import java.lang.reflect.InvocationTargetException ;
18 import java.lang.reflect.Method ;
19
20 import org.eclipse.core.databinding.BindingException;
21 import org.eclipse.core.databinding.beans.BeansObservables;
22 import org.eclipse.core.databinding.beans.IBeanObservable;
23 import org.eclipse.core.databinding.observable.Diffs;
24 import org.eclipse.core.databinding.observable.Realm;
25 import org.eclipse.core.databinding.observable.value.AbstractObservableValue;
26 import org.eclipse.core.databinding.observable.value.ValueDiff;
27 import org.eclipse.core.databinding.util.Policy;
28 import org.eclipse.core.runtime.IStatus;
29 import org.eclipse.core.runtime.Status;
30
31
35 public class JavaBeanObservableValue extends AbstractObservableValue implements IBeanObservable {
36 private final Object object;
37 private boolean updating = false;
38
39 private final PropertyDescriptor propertyDescriptor;
40 private final Class overrideType;
41 private ListenerSupport listenerSupport;
42
43
49 public JavaBeanObservableValue(Realm realm, Object object,
50 PropertyDescriptor descriptor, Class overrideType) {
51 super(realm);
52 this.object = object;
53 this.propertyDescriptor = descriptor;
54 this.overrideType = overrideType;
55 }
56
57 protected void firstListenerAdded() {
58 PropertyChangeListener listener = new PropertyChangeListener () {
59 public void propertyChange(java.beans.PropertyChangeEvent event) {
60 if (!updating) {
61 final ValueDiff diff = Diffs.createValueDiff(event.getOldValue(),
62 event.getNewValue());
63 getRealm().exec(new Runnable (){
64 public void run() {
65 fireValueChange(diff);
66 }});
67 }
68 }
69 };
70
71 if (listenerSupport == null) {
72 listenerSupport = new ListenerSupport(listener, propertyDescriptor.getName());
73 }
74
75 listenerSupport.hookListener(object);
76 }
77
78 public void doSetValue(Object value) {
79 updating = true;
80 try {
81 Object oldValue = doGetValue();
82 Method writeMethod = propertyDescriptor.getWriteMethod();
83 if (!writeMethod.isAccessible()) {
84 writeMethod.setAccessible(true);
85 }
86 writeMethod.invoke(object, new Object [] { value });
87 fireValueChange(Diffs.createValueDiff(oldValue, doGetValue()));
88 } catch (InvocationTargetException e) {
89
93 throw new RuntimeException (e.getCause());
94 } catch (Exception e) {
95 if (BeansObservables.DEBUG) {
96 Policy
97 .getLog()
98 .log(
99 new Status(
100 IStatus.WARNING,
101 Policy.JFACE_DATABINDING,
102 IStatus.OK,
103 "Could not change value of " + object + "." + propertyDescriptor.getName(), e)); }
105 } finally {
106 updating = false;
107 }
108 }
109
110 public Object doGetValue() {
111 try {
112 Method readMethod = propertyDescriptor.getReadMethod();
113 if (readMethod == null) {
114 throw new BindingException(propertyDescriptor.getName()
115 + " property does not have a read method."); }
117 if (!readMethod.isAccessible()) {
118 readMethod.setAccessible(true);
119 }
120 return readMethod.invoke(object, null);
121 } catch (InvocationTargetException e) {
122
126 throw new RuntimeException (e.getCause());
127 } catch (Exception e) {
128 if (BeansObservables.DEBUG) {
129 Policy
130 .getLog()
131 .log(
132 new Status(
133 IStatus.WARNING,
134 Policy.JFACE_DATABINDING,
135 IStatus.OK,
136 "Could not read value of " + object + "." + propertyDescriptor.getName(), e)); }
138 return null;
139 }
140 }
141
142 protected void lastListenerRemoved() {
143 unhookListener();
144 }
145
146 private void unhookListener() {
147 if (listenerSupport != null) {
148 listenerSupport.dispose();
149 listenerSupport = null;
150 }
151 }
152
153 public Object getValueType() {
154 Class type = propertyDescriptor.getPropertyType();
155 if (type == Object .class && overrideType != null)
156 type = overrideType;
157 return type;
158 }
159
160 public Object getObserved() {
161 return object;
162 }
163
164 public PropertyDescriptor getPropertyDescriptor() {
165 return propertyDescriptor;
166 }
167
168 public synchronized void dispose() {
169 unhookListener();
170 super.dispose();
171 }
172 }
173 |
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