Package com.vaadin.flow.data.provider

Interface CallbackDataProvider.CountCallback<T,​F>

  • Type Parameters:
    T - the type of the items to count
    F - the type of the optional filter in the query, Void if filtering is not supported
    All Superinterfaces:
    Serializable
    Enclosing class:
    CallbackDataProvider<T,​F>
    Functional Interface:
    This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
    @FunctionalInterface
public static interface CallbackDataProvider.CountCallback<T,​F>
extends Serializable
    Callback interface for counting the number of items in a backend based on a query.

    • Method Detail

      • count

        int count​(Query<T,​F> query)
        Counts the number of available items based on a query. The query optionally defines any filtering to use through Query.getFilter(). The query also contains information about paging and sorting although that information is generally not applicable for determining the number of items.
        Parameters:
        query - the query that defines which items to count
        Returns:
        the number of available items