Package com.vaadin.flow.data.provider

Class AbstractDataProvider<T,F>

java.lang.Object

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

Type Parameters:

T - data type

F - filter type

All Implemented Interfaces:

DataProvider<T,F>, Serializable

Direct Known Subclasses:

AbstractBackEndDataProvider, AbstractHierarchicalDataProvider, ListDataProvider

public abstract class AbstractDataProvider<T,F>
extends Object
implements DataProvider<T,F>

Abstract data provider implementation which takes care of refreshing data from the underlying data provider.

Since:

1.0

Author:

Vaadin Ltd

See Also:

• Serialized Form

Constructor Summary

Constructors

Constructor	Description
AbstractDataProvider()

Method Summary

Modifier and Type	Method	Description
Registration	addDataProviderListener(DataProviderListener<T> listener)	Adds a data provider listener.
protected <E> Registration	addListener(Class<E> eventType, SerializableConsumer<E> method)	Registers a new listener with the specified activation method to listen events generated by this component.
protected void	fireEvent(EventObject event)	Sends the event to all listeners.
void	refreshAll()	Refreshes all data based on currently available data in the underlying provider.
void	refreshItem(T item)	Refreshes the given item.
void	refreshItem(T item, boolean refreshChildren)	Refreshes the given item and all of the children of the item as well.

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

fetch, getId, isInMemory, size, withConfigurableFilter, withConfigurableFilter, withConvertedFilter

Constructor Details

AbstractDataProvider

public AbstractDataProvider()

Method Details

addDataProviderListener

public Registration addDataProviderListener(DataProviderListener<T> listener)

Description copied from interface: DataProvider

Adds a data provider listener. The listener is called when some piece of data is updated.

The DataProvider.refreshAll() method fires DataChangeEvent each time when it's called. It allows to update UI components when user changes something in the underlying data.

Specified by:

addDataProviderListener in interface DataProvider<T,F>

Parameters:

listener - the data change listener, not null

Returns:

a registration for the listener

See Also:

• DataProvider.refreshAll()

refreshAll

public void refreshAll()

Description copied from interface: DataProvider

Refreshes all data based on currently available data in the underlying provider.

Specified by:

refreshAll in interface DataProvider<T,F>

refreshItem

public void refreshItem(T item,
 boolean refreshChildren)

Description copied from interface: DataProvider

Refreshes the given item and all of the children of the item as well.

Specified by:

refreshItem in interface DataProvider<T,F>

Parameters:

item - the item to refresh

refreshChildren - whether or not to refresh child items

See Also:

• By default it just does a standard refreshItem, in a hierarchical DataProvider it is supposed to refresh all of the children as well in case 'refreshChildren' is true.

refreshItem

public void refreshItem(T item)

Description copied from interface: DataProvider

Refreshes the given item. This method should be used to inform all DataProviderListeners that an item has been updated or replaced with a new instance.

For this to work properly, the item must either implement Object.equals(Object) and Object.hashCode() to consider both the old and the new item instances to be equal, or alternatively DataProvider.getId(Object) should be implemented to return an appropriate identifier.

Specified by:

refreshItem in interface DataProvider<T,F>

Parameters:

item - the item to refresh

See Also:

• DataProvider.getId(Object)

addListener

protected <E> Registration addListener(Class<E> eventType,
 SerializableConsumer<E> method)

Registers a new listener with the specified activation method to listen events generated by this component. If the activation method does not have any arguments the event object will not be passed to it when it's called.

Type Parameters:

E - the event type

Parameters:

eventType - the type of the listened event. Events of this type or its subclasses activate the listener.

method - the consumer to receive the event.

Returns:

a registration for the listener

fireEvent

protected void fireEvent(EventObject event)

Sends the event to all listeners.

Parameters:

event - the Event to be sent to all listeners.