/*
* Licensed to the Apache Software Foundation (ASF) under one or more contributor license
* agreements. See the NOTICE file distributed with this work for additional information regarding
* copyright ownership. The ASF licenses this file to You 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.apache.geode.cache.util;
/**
* Abstract class for CqListener. Utility class that implements all methods in
* <code>CqListener</code> with empty implementations. Applications can subclass this class and only
* override the methods of interest.
*
* @since GemFire 5.1
*/
import org.apache.geode.cache.query.CqListener;
import org.apache.geode.cache.query.CqEvent;
public abstract class CqListenerAdapter implements CqListener {
/**
* An event occurred that modifies the results of the query. This event does not contain an error.
*/
public void onEvent(CqEvent aCqEvent) {}
/**
* An error occurred in the processing of a CQ. This event does contain an error. The newValue and
* oldValue in the event may or may not be available, and will be null if not available.
*/
public void onError(CqEvent aCqEvent) {}
/**
* Called when the CQ is closed, the base region is destroyed, when the cache is closed, or when
* this listener is removed from a CqQuery using a <code>CqAttributesMutator</code>.
*
* <p>
* Implementations should cleanup any external resources such as database connections. Any runtime
* exceptions this method throws will be logged.
*
* <p>
* It is possible for this method to be called multiple times on a single callback instance, so
* implementations must be tolerant of this.
*
* @see org.apache.geode.cache.CacheCallback#close
*/
public void close() {}
}