/**
* A property in the observed bean has changed. First checks, if this listener should handle the
* event, because the event's property name is the one to be observed or the event indicates
* that any property may have changed. In case the event provides no new value, it is read from
* the source bean.
*
* @param evt the property change event to be handled
*/
public void propertyChange(PropertyChangeEvent evt) {
String sourcePropertyName = sourcePropertyDescriptor.getName();
if ((evt.getPropertyName() == null) || (evt.getPropertyName().equals(sourcePropertyName))) {
Object newValue = evt.getNewValue();
if (newValue == null) {
newValue = BeanUtils.getValue(sourceBean, sourcePropertyDescriptor);
}
setValueSilently(
sourceBean, sourcePropertyDescriptor, targetBean, targetPropertyDescriptor, newValue);
}
}
private void setValueSilently(
Object sourceBean,
PropertyDescriptor sourcePropertyDescriptor,
Object targetBean,
PropertyDescriptor targetPropertyDescriptor,
Object newValue) {
if (property1ChangeHandler != null) {
removePropertyChangeHandler(bean1, bean1Class, property1ChangeHandler);
}
if (property2ChangeHandler != null) {
removePropertyChangeHandler(bean2, bean2Class, property2ChangeHandler);
}
try {
// Set the new value in the target bean.
BeanUtils.setValue(targetBean, targetPropertyDescriptor, newValue);
} catch (PropertyVetoException e) {
// Silently ignore this situation here, will be handled below.
}
// The target bean setter may have modified the new value.
// Read the value set in the target bean.
Object value = BeanUtils.getValue(targetBean, targetPropertyDescriptor);
// If the new value and the value read differ,
// update the source bean's value.
// This ignores that the source bean setter may modify the value again.
// But we won't end in a loop.
if (!BindingUtils.equals(value, newValue)) {
boolean sourcePropertyWritable = sourcePropertyDescriptor.getWriteMethod() != null;
if (sourcePropertyWritable) {
try {
BeanUtils.setValue(sourceBean, sourcePropertyDescriptor, value);
} catch (PropertyVetoException e) {
// Ignore. The value set is a modified variant
// of a value that had been accepted before.
}
}
}
if (property1ChangeHandler != null) {
addPropertyChangeHandler(bean1, bean1Class, property1ChangeHandler);
}
if (property2ChangeHandler != null) {
addPropertyChangeHandler(bean2, bean2Class, property2ChangeHandler);
}
}
/**
* Reads the value of the first bean property and sets it as new value of the second bean
* property.
*
* @see #updateProperty1()
*/
public void updateProperty2() {
Object property1Value = BeanUtils.getValue(bean1, property1Descriptor);
setValueSilently(bean1, property1Descriptor, bean2, property2Descriptor, property1Value);
}