Per the Java doc of http://javaserverfaces.java.net/nonav/docs/2.0/javadocs/javax/faces/component/UIComponent.html#getChildren(), if I set an existing child in the returned children list, the target child should be removed from its previous parent in both children and facet list. While currently MyFaces seems only remove from the children list. And for the facet map, now it only remove from the facet map. Is it a bug for MyFaces ?
public abstract List<UIComponent> getChildren()
Return a mutable List representing the child UIComponents associated with this component. The returned implementation must support all of the standard and optional List methods, plus support the following additional requirements:
The List implementation must implement the java.io.Serializable interface.
Any attempt to add a null must throw a NullPointerException
Any attempt to add an object that does not implement UIComponent must throw a ClassCastException.
Whenever a new child component is added, the parent property of the child must be set to this component instance. If the parent property of the child was already non-null, the child must first be removed from its previous parent (where it may have been either a child or a facet).
Whenever an existing child component is removed, the parent property of the child must be set to null.
After the child component has been added to the view, if the following condition is not met:
FacesContext.isPostback() returns true and FacesContext.getCurrentPhaseId() returns PhaseId.RESTORE_VIEW
Application.publishEvent(javax.faces.context.FacesContext, java.lang.Class, java.lang.Object) must be called, passing PostAddToViewEvent.class as the first argument and the newly added component as the second argument.