Package com.vaadin.flow.data.provider.hierarchy

Class AbstractHierarchicalDataProvider<T,F>

java.lang.Object

com.vaadin.flow.data.provider.AbstractDataProvider<T,F>

com.vaadin.flow.data.provider.hierarchy.AbstractHierarchicalDataProvider<T,F>

Type Parameters:

T - data type

F - filter type

All Implemented Interfaces:

DataProvider<T,F>, HierarchicalDataProvider<T,F>, Serializable

Direct Known Subclasses:

AbstractBackEndHierarchicalDataProvider, TreeDataProvider

public abstract class AbstractHierarchicalDataProvider<T,F>
extends AbstractDataProvider<T,F>
implements HierarchicalDataProvider<T,F>

Abstract hierarchical data provider implementation which takes care of item refreshes and associated events.

Since:

1.2

Author:

Vaadin Ltd

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from interface com.vaadin.flow.data.provider.hierarchy.HierarchicalDataProvider

HierarchicalDataProvider.HierarchyFormat

Constructor Summary

Constructors

Constructor	Description
AbstractHierarchicalDataProvider()

Method Summary

Modifier and Type	Method	Description
void	refreshItem(T item, boolean refreshChildren)	Refreshes the given item and its children when refreshChildren is true.
HierarchicalConfigurableFilterDataProvider<T,Void,F>	withConfigurableFilter()	Wraps this data provider to create a data provider that supports programmatically setting a filter but no filtering through the query.
<Q, C> HierarchicalConfigurableFilterDataProvider<T,Q,C>	withConfigurableFilter(SerializableBiFunction<Q,C,F> filterCombiner)	Wraps this data provider to create a data provider that supports programmatically setting a filter that will be combined with a filter provided through the query.
<C> HierarchicalDataProvider<T,C>	withConvertedFilter(SerializableFunction<C,F> filterConverter)	Wraps this data provider to create a data provider that uses a different filter type.

Methods inherited from class com.vaadin.flow.data.provider.AbstractDataProvider

addDataProviderListener, addListener, fireEvent, refreshAll, refreshItem

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.vaadin.flow.data.provider.DataProvider

addDataProviderListener, getId, isInMemory, refreshAll, refreshItem

Methods inherited from interface com.vaadin.flow.data.provider.hierarchy.HierarchicalDataProvider

fetch, fetchChildren, getChildCount, getDepth, getHierarchyFormat, getItemIndex, getParent, hasChildren, size

Constructor Details

AbstractHierarchicalDataProvider

public AbstractHierarchicalDataProvider()

Method Details

refreshItem

public void refreshItem(T item,
 boolean refreshChildren)

Description copied from interface: DataProvider

Refreshes the given item and its children when refreshChildren is true.

This method will reset the item's cached hierarchy which can cause a content shift if the item also contains expanded children: their descendants aren't guaranteed to be re-fetched eagerly if they aren't visible, which may affect the overall size of the rendered hierarchy, leading to content shifts.

This method is only supported for hierarchical data providers that use HierarchicalDataProvider.HierarchyFormat.NESTED.

Specified by:

refreshItem in interface DataProvider<T,F>

Overrides:

refreshItem in class AbstractDataProvider<T,F>

Parameters:

item - the item to refresh

refreshChildren - whether or not to refresh child items

Throws:

UnsupportedOperationException - if the hierarchy format is not HierarchicalDataProvider.HierarchyFormat.NESTED

withConfigurableFilter

public <Q,
C>
HierarchicalConfigurableFilterDataProvider<T,Q,C> withConfigurableFilter(SerializableBiFunction<Q,C,F> filterCombiner)

Description copied from interface: DataProvider

Wraps this data provider to create a data provider that supports programmatically setting a filter that will be combined with a filter provided through the query.

Specified by:

withConfigurableFilter in interface DataProvider<T,F>

Specified by:

withConfigurableFilter in interface HierarchicalDataProvider<T,F>

Type Parameters:

Q - the query filter type

C - the configurable filter type

Parameters:

filterCombiner - a callback for combining and the configured filter with the filter from the query to get a filter to pass to the wrapped provider. Either parameter might be null, but the callback will not be invoked at all if both would be null. Not null.

Returns:

a data provider with a configurable filter, not null

See Also:

• DataProvider.withConfigurableFilter()
• ConfigurableFilterDataProvider.setFilter(Object)

withConvertedFilter

public <C> HierarchicalDataProvider<T,C> withConvertedFilter(SerializableFunction<C,F> filterConverter)

Description copied from interface: DataProvider

Wraps this data provider to create a data provider that uses a different filter type. This can be used for adapting this data provider to a filter type provided by a Component such as ComboBox.

For example receiving a String from ComboBox and making a Predicate based on it:

 DataProvider<Person, Predicate<Person>> dataProvider;
 // ComboBox uses String as the filter type
 DataProvider<Person, String> wrappedProvider = dataProvider
         .withConvertedFilter(filterText -> {
             Predicate<Person> predicate = person -> person.getName()
                     .startsWith(filterText);
             return predicate;
         });
 comboBox.setDataProvider(wrappedProvider);
 

Specified by:

withConvertedFilter in interface DataProvider<T,F>

Specified by:

withConvertedFilter in interface HierarchicalDataProvider<T,F>

Type Parameters:

C - the filter type that the wrapped data provider accepts; typically provided by a Component

Parameters:

filterConverter - callback that converts the filter in the query of the wrapped data provider into a filter supported by this data provider. Will only be called if the query contains a filter. Not null

Returns:

wrapped data provider, not null

withConfigurableFilter

public HierarchicalConfigurableFilterDataProvider<T,Void,F> withConfigurableFilter()

Description copied from interface: DataProvider

Wraps this data provider to create a data provider that supports programmatically setting a filter but no filtering through the query.

Specified by:

withConfigurableFilter in interface DataProvider<T,F>

Specified by:

withConfigurableFilter in interface HierarchicalDataProvider<T,F>

Returns:

a data provider with a configurable filter, not null

See Also:

• DataProvider.withConfigurableFilter(SerializableBiFunction)
• ConfigurableFilterDataProvider.setFilter(Object)