Java Vaadin controls - ControlHelper getParent()

Vaadin controls, just like every other UI, creates a child-parent tree. This class helps to retrieve parent of a specified type. getParent() is extremely useful when invoked deep withing the tree structure to e.g. retrieve the main tab control and close it.


/**
 * The purpose of this class is to help with the management of Vaadin controls child-parent tree.
 */
public class ControlHelper {

    private static final int _MAXIMUM_PARENT_ITERATION_COUNT = 100;

    /**
     * Get parent of the control which has a specified type.
     *
     * @param cls type of the control to return
     * @param control origin control (where to start traversing the tree)
     * @param <T>
     * @return
     */
    public static <T extends AbstractComponent> T getParent(Class<T> cls, AbstractComponent control)
    {
       if (control == null)
           return null;

        AbstractComponent parent = control;

       for (int i = 0; i < _MAXIMUM_PARENT_ITERATION_COUNT; i++)
       {
           if (parent.getParent() == null)
               return null;

           //Return parent of the desired class type
           if (parent.getParent().getClass().isAssignableFrom(cls))
               return (T) parent.getParent();

           parent = (AbstractComponent) parent.getParent();
       }

       return null;
    }
}