a snippet like

        BooleanProperty bp = new SimpleBooleanProperty();
        ObjectProperty<Boolean> op = new SimpleObjectProperty<>();
        bp.bindBidirectional(op);

produces:

Jun 12, 2014 4:45:43 PM javafx.beans.property.BooleanProperty setValue
INFORMATION: Attempt to set boolean property to null, using default value instead.
java.lang.NullPointerException
at javafx.beans.property.BooleanProperty.setValue(BooleanProperty.java:74)
        ... many lines more

information messages like that shouldn't show up: either the binding is illegal and should throw an Exception or the target property can handle it and must do so without public shouting. Second applies here, so remove or log at a finer level and/or document in the api