在J2EE中,以下是firePropertyChange的原型,正确的是()。 
A、public void firePropertyChange(PropertyChangeListener l,String oldValue, String newValue)
B、public void firePropertyChange(String propertyName, Object oldValue, Object newValue)
C、public void firePropertyChange(PropertyChangeSupport changes)
D、public void firePropertyChange(Object oldValue, Object newValue)