Java SE (Java Platform, Standard Edition)

This should be pretty simple.  The javadoc for Bindings#selectString says:

Creates a binding used to get a member, such as a.b.c. The value of the binding will be c, or "" if c could not be reached (due to b not having a c property, b being null, or c not being a String etc.).

Running this example:

import javafx.beans.binding.Bindings;
import javafx.beans.binding.StringBinding;
import javafx.beans.property.*;


public class SelectBindingExample {
    public static void main(String[] args) {
        ParentModel parentModel = new ParentModel();
        StringBinding bindingA = createBinding(parentModel);
        String nameA = bindingA.get(); // NPE while evaluating
        System.out.println("Bound value is " + (nameA != null ? nameA : "null") + ".");


        parentModel.setChildModel(new ChildModel());
        StringBinding bindingB = createBinding(parentModel);
        String nameB = bindingB.get();
        System.out.println("Bound value is " + (nameB != null ? nameB : "null") + ".");
    }


    private static StringBinding createBinding(ParentModel parentModel) {
        return Bindings.selectString(parentModel.childModelProperty(), "name");
    }


    public static class ParentModel {
        private final ObjectProperty<ChildModel> childModel = new SimpleObjectProperty<>();
        public final ReadOnlyObjectProperty<ChildModel> childModelProperty() {return childModel;}
        public final ChildModel getChildModel() {return childModel.get();}
        public final void setChildModel(ChildModel childModel) {this.childModel.set(childModel);}
    }


    public static class ChildModel {
        private final StringProperty name = new SimpleStringProperty("Child Model Name");
        public final ReadOnlyStringProperty nameProperty() {return name;}
        public final String getName() {return name.get();}
        protected final void setName(String name) {this.name.set(name);}
    }
}

..causes a NPE while evaluating the binding:

WARNING: Exception while evaluating select-binding [name]
Jan 24, 2014 7:10:57 AM com.sun.javafx.binding.SelectBinding$SelectBindingHelper getObservableValue
INFO: Property 'name' in ReadOnlyObjectProperty [bean: SelectBindingExample$ParentModel@4437c4, name: childModel, value: null] is null
java.lang.NullPointerException
  at com.sun.javafx.binding.SelectBinding$SelectBindingHelper.getObservableValue(SelectBinding.java:481)
  at com.sun.javafx.binding.SelectBinding$AsString.computeValue(SelectBinding.java:394)
  at javafx.beans.binding.StringBinding.get(StringBinding.java:152)
  at SelectBindingExample.main(SelectBindingExample.java:9)
  at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
  at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  at java.lang.reflect.Method.invoke(Method.java:483)
  at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)

What's going wrong here?  I've updated the example to work with the Bindings#selectString method from Java 7 and things work as expected.  Is this a bug?

Slight modification to the example so it works with Java 7.