APropertyChangeSupported.java 文件源码

/**
 * This is the same as in the original java beans implementation with the exception that changes from null to null
 * are not reported as property change events!
 * 
 * @see java.beans.PropertyChangeSupport#fireIndexedPropertyChange(java.lang.String, int, java.lang.Object,
 *      java.lang.Object)
 */
public void fireIndexedPropertyChange(final String propertyName, final int index, final Object oldValue,
        final Object newValue) {
    final PropertyChangeSupport ref = lazyGetPropertyChangeSupport(false);
    if (ref != null && (!Objects.equalsProperty(oldValue, newValue)
            || !equalsPropertyChangeListeners(oldValue, newValue))) {
        final IndexedPropertyChangeEvent event = new IndexedPropertyChangeEvent(this, propertyName, oldValue,
                newValue, index);
        fireEvent(ref, propertyName, event);
    }
}