Package com.vaadin.flow.data.provider

Class AbstractBackEndDataProvider<T,F>

java.lang.Object
com.vaadin.flow.data.provider.AbstractDataProvider<T,F>
com.vaadin.flow.data.provider.AbstractBackEndDataProvider<T,F>
Type Parameters:
T - data provider data type
F - data provider filter type
All Implemented Interfaces:
BackEndDataProvider<T,F>, DataProvider<T,F>, Serializable
Direct Known Subclasses:
CallbackDataProvider
public abstract class AbstractBackEndDataProvider<T,F> extends AbstractDataProvider<T,F> implements BackEndDataProvider<T,F>
Abstract base class for implementing back end data providers.
Since:
1.0
See Also:

  • Constructor Details

    • AbstractBackEndDataProvider

      public AbstractBackEndDataProvider()

  • Method Details

    • fetch

      public Stream<T> fetch(Query<T,F> query)
      Description copied from interface: DataProvider
      Fetches data from this DataProvider using given query.
      Specified by:
      fetch in interface DataProvider<T,F>
      Parameters:
      query - given query to request data
      Returns:
      the result of the query request: a stream of data objects, not null

    • size

      public int size(Query<T,F> query)
      Description copied from interface: DataProvider
      Gets the amount of data in this DataProvider.
      Specified by:
      size in interface DataProvider<T,F>
      Parameters:
      query - query with sorting and filtering
      Returns:
      the size of the data provider

    • fetchFromBackEnd

      protected abstract Stream<T> fetchFromBackEnd(Query<T,F> query)
      Fetches data from the back end using the given query.
      Parameters:
      query - the query that defines sorting, filtering and paging for fetching the data
      Returns:
      a stream of items matching the query

    • sizeInBackEnd

      protected abstract int sizeInBackEnd(Query<T,F> query)
      Counts the number of items available in the back end.
      Parameters:
      query - the query that defines filtering to be used for counting the number of items
      Returns:
      the number of available items

    • setSortOrders

      public void setSortOrders(List<QuerySortOrder> sortOrders)
      Description copied from interface: BackEndDataProvider
      Sets a list of sort orders to use as the default sorting for this data provider. This overrides the sorting set by any other method that manipulates the default sorting of this data provider.

      The default sorting is used if the query defines no sorting. The default sorting is also used to determine the ordering of items that are considered equal by the sorting defined in the query.

      Specified by:
      setSortOrders in interface BackEndDataProvider<T,F>
      Parameters:
      sortOrders - a list of sort orders to set, not null
      See Also: