com.vaadin.event.DataBoundTransferable Maven / Gradle / Ivy
/*
* Vaadin Framework 7
*
* Copyright (C) 2000-2024 Vaadin Ltd
*
* This program is available under Vaadin Commercial License and Service Terms.
*
* See for the full
* license.
*/
package com.vaadin.event;
import java.util.Map;
import com.vaadin.data.Container;
import com.vaadin.ui.Component;
/**
* Parent class for {@link Transferable} implementations that have a Vaadin
* container as a data source. The transfer is associated with an item
* (identified by its Id) and optionally also a property identifier (e.g. a
* table column identifier when transferring a single table cell).
*
* The component must implement the interface {@link Container.Viewer}.
*
* In most cases, receivers of data transfers should depend on this class
* instead of its concrete subclasses.
*
* @since 6.3
*/
public abstract class DataBoundTransferable extends TransferableImpl {
public DataBoundTransferable(Component sourceComponent,
Map rawVariables) {
super(sourceComponent, rawVariables);
}
/**
* Returns the identifier of the item being transferred.
*
* @return item identifier
*/
public abstract Object getItemId();
/**
* Returns the optional property identifier that the transfer concerns.
*
* This can be e.g. the table column from which a drag operation originated.
*
* @return property identifier
*/
public abstract Object getPropertyId();
/**
* Returns the container data source from which the transfer occurs.
*
* {@link Container.Viewer#getContainerDataSource()} is used to obtain the
* underlying container of the source component.
*
* @return Container
*/
public Container getSourceContainer() {
Component sourceComponent = getSourceComponent();
if (sourceComponent instanceof Container.Viewer) {
return ((Container.Viewer) sourceComponent)
.getContainerDataSource();
} else {
// this should not happen
return null;
}
}
}