/*
* Copyright 2015 Petr Bouda
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.joyrest.examples.combiner.store;
/**
* A Datastore which implements this interface is able to notify all {@link DataStoreObserver observers} and react to an adding
* or a
* removing entities.
* <p>
* The order in which notifications will be delivered to multiple observers is not specified.
* </p>
*
* @author Petr Bouda
**/
public interface ObservableDataStore extends InMemoryDataStore {
/**
* Adds an {@link DataStoreObserver observer} to the set of observers for this observable object {@link ObservableDataStore}.
*
* @param observer an observer to be added.
* @throws NullPointerException if the parameter o is null.
*/
void addObserver(DataStoreObserver observer);
/**
* Deletes an {@link DataStoreObserver observer} from the set of observers of this object.
*
* Passing {@code null} to this method will have no effect.
*
* @param observer the observer to be deleted.
*/
void deleteObserver(DataStoreObserver observer);
}