com.vaadin.collaborationengine.ListChangeEvent Maven / Gradle / Ivy
/*
* Copyright 2020-2022 Vaadin Ltd.
*
* This program is available under Commercial Vaadin Runtime License 1.0
* (CVRLv1).
*
* For the full License, see http://vaadin.com/license/cvrl-1
*/
package com.vaadin.collaborationengine;
import java.util.EventObject;
import java.util.Optional;
import java.util.function.Function;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.JsonNode;
/**
* Event that is fired when the value in a collaboration list changes.
*
* @author Vaadin Ltd
* @since 3.1
*/
public class ListChangeEvent extends EventObject {
private final ListChange change;
/**
* Creates a new event.
*
* @param list
* the list source of the event
* @param change
* the list change
*/
ListChangeEvent(CollaborationList list, ListChange change) {
super(list);
this.change = change;
}
@Override
public CollaborationList getSource() {
return (CollaborationList) super.getSource();
}
ListChangeType getType() {
return change.getType();
}
/**
* Gets the key of the list item affected by the change.
*
* @return the key of the changed item, not null
*/
public ListKey getKey() {
return new ListKey(change.getKey());
}
/**
* Gets the current value of the list item affected by the change as
* instance of the given class.
*
* If the item was removed by the change, this method returns
* null and {@link #getOldValue(Class)} return the removed item
* value.
*
* @param
* the type of the value from type parameter, e.g.
* String
* @param type
* the expected type of the returned instance
* @return the current value of the item affected by the change
*/
public T getValue(Class type) {
return JsonUtil.toInstance(change.getValue(), type);
}
/**
* Gets the current value of the list item affected by the change as
* instance corresponding to the given type reference.
*
* If the item was removed by the change, this method returns
* null and {@link #getOldValue(TypeReference)} return the
* removed item value.
*
* @param
* the type reference of the value from type
* parameter, e.g. List
* @param type
* the expected type reference of the returned instance
* @return the current value of the item affected by the change
*/
public T getValue(TypeReference type) {
return JsonUtil.toInstance(change.getValue(), type);
}
/**
* Gets the old value of the list item affected by the change as instance of
* the given class.
*
* @param
* the type of the value from type parameter, e.g.
* String
* @param type
* the expected type of the returned instance
* @return the old value of the item affected by the change
*/
public T getOldValue(Class type) {
return JsonUtil.toInstance(change.getOldValue(), type);
}
/**
* Gets the old value of the list item affected by the change as instance
* corresponding to the given type reference.
*
* @param
* the type reference of the value from type
* parameter, e.g. List
* @param type
* the expected type reference of the returned instance
* @return the old value of the item affected by the change
*/
public T getOldValue(TypeReference type) {
return JsonUtil.toInstance(change.getOldValue(), type);
}
/**
* Gets the key of the item which is after the current item after the
* change.
*
* @return the key of the item which is after the current item, or
* null if there is none
*/
public ListKey getNext() {
return ListKey.of(change.getNext());
}
/**
* Gets the key of the item which was after the current item before the
* change.
*
* @return the key of the item which was after the current item, or
* null if there was none
*/
public ListKey getOldNext() {
return ListKey.of(change.getOldNext());
}
/**
* Gets the key of the item which is before the current item after the
* change.
*
* @return the key of the item which is before the current item, or
* null if there is none
*/
public ListKey getPrev() {
return ListKey.of(change.getPrev());
}
/**
* Gets the key of the item which was before the current item before the
* change.
*
* @return the key of the item which was before the current item, or
* null if there was none
*/
public ListKey getOldPrev() {
return ListKey.of(change.getOldPrev());
}
/**
* Gets the added item as instance of the given class.
*
* @param type
* the class of the expected type of the returned instance
* @param
* the type of the class given as the type argument
* @return the added item, or an empty optional if no item was added
*
* @deprecated This method is preserved for backwards compatibility from the
* initial version when the only possible list change was to add
* a new item to the end of the list.
*/
@Deprecated
public Optional getAddedItem(Class type) {
return convertAddedItem(JsonUtil.fromJsonConverter(type));
}
/**
* Gets the added item as instance of the given type reference.
*
* @param type
* the expected type reference of the returned instance
* @param
* the type of the reference given as the type
* argument
* @return the added item, or an empty optional if no item was added
*
* @deprecated This method is preserved for backwards compatibility from the
* initial version when the only possible list change was to add
* a new item to the end of the list.
*/
@Deprecated
public Optional getAddedItem(TypeReference type) {
return convertAddedItem(JsonUtil.fromJsonConverter(type));
}
private Optional convertAddedItem(Function converter) {
if (change.getType() != ListChangeType.INSERT) {
return Optional.empty();
}
return Optional.ofNullable(change.getValue()).map(converter);
}
}