/*
* Copyright 2015-2016 the original author or authors.
*
* 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.springframework.integration.metadata;
/**
* A callback to be invoked whenever a value changes in the data store.
*
* @author Marius Bogoevici
* @since 4.2
*/
public interface MetadataStoreListener {
/**
* Invoked when a key is added to the store
*
* @param key the key being added
* @param value the value being added
*/
void onAdd(String key, String value);
/**
* Invoked when a key is removed from the store
*
* @param key the key being removed
* @param oldValue the value being removed
*/
void onRemove(String key, String oldValue);
/**
* Invoked when a key is updated into the store
* @param key the key being updated
* @param newValue the new value
*/
void onUpdate(String key, String newValue);
}