HierarchicalBeanContainer.java

/**
 * Extends HierarchicalContainer which provides proper support for sorting and filtering, and add bean capabilities to it.
 */
public class HierarchicalBeanContainer<IDTYPE, BEANTYPE> extends HierarchicalContainer {

    private final BeanContainer<IDTYPE, BEANTYPE> properties;

    public HierarchicalBeanContainer(Class<BEANTYPE> itemClass) {
        properties = new BeanContainer<>(itemClass);
        properties.getContainerPropertyIds().forEach(prop -> addContainerProperty(prop, properties.getType(prop), null));
    }

    private String propertyId = null;

    /**
     * Sets the bean id resolver to use a property of the beans as the
     * identifier.
     *
     * @param propertyId
     *            the identifier of the property to use to find item identifiers
     */
    public void setBeanIdProperty(String propertyId) {
        if (!properties.getContainerPropertyIds().contains(propertyId)) {
            throw new IllegalArgumentException("propertyId: unknown property " + propertyId + "; supported properties: " + properties.getContainerPropertyIds());
        }
        this.propertyId = propertyId;
    }

    /**
     * Adds a bean to the container using the bean item id resolver to find its
     * identifier.
     *
     * A bean id resolver must be set before calling this method.
     *
     * @param bean
     *            the bean to add
     * @return Item<BEANTYPE> item added or null
     * @throws IllegalStateException
     *             if no bean identifier resolver has been set
     * @throws IllegalArgumentException
     *             if an identifier cannot be resolved for the bean
     */
    public Item addBean(BEANTYPE bean)
            throws IllegalStateException, IllegalArgumentException {
        if (bean == null) {
            return null;
        }
        if (propertyId == null) {
            throw new IllegalStateException("propertyId is not set");
        }
        final BeanItem<BEANTYPE> beanItem = new BeanItem<>(bean);
        final IDTYPE itemId = (IDTYPE) beanItem.getItemProperty(propertyId).getValue();
        if (itemId == null) {
            throw new IllegalArgumentException(
                    "Resolved identifier for a bean must not be null");
        }
        final Item item = addItem(itemId);
        properties.getContainerPropertyIds().forEach(prop -> item.getItemProperty(prop).setValue(beanItem.getItemProperty(prop).getValue()));
        return item;
    }

    public void addAll(Collection<? extends BEANTYPE> beans) {
        beans.forEach(this::addBean);
    }
}