class PartDefinitionImpl implements
        PartDefinition {

    @Override
    public void setParentPanel(final PanelDefinition parentPanel) {
        if (parentPanel != null && this.parentPanel != null) {
            throw new IllegalStateException("Can't set parent: this part already belongs to " + this.parentPanel);
        }
        this.parentPanel = parentPanel;
    }

    public  PartDefinitionImpl();
    public  PartDefinitionImpl(final PlaceRequest place);

}