/*
* 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.query;
import org.apache.geode.cache.Operation;
/**
* This interface provides methods to get all the information sent from the server about the CQ
* event. The CqEvent is passed to the CQs CqListener methods. It can be used to retrieve such
* information as the region operation, CQ operation associated with the event, the new key and
* value from the event, and the CqQuery object associated with the event. The CqEvent is not an
* extension of CacheEvent.
*
* @since GemFire 5.5
*/
public interface CqEvent {
/**
* Get the CqQuery object of this event.
*
* @see CqQuery
* @return CqQuery object.
*/
public CqQuery getCq();
/**
* Get the operation on the base region that triggered this event.
*
* @return Operation operation on the base region (on which CQ is created).
*/
public Operation getBaseOperation();
/**
* Get the operation on the query results. Supported operations include update, create, destroy,
* region clear and region invalidate.
*
* @return Operation operation with respect to CQ.
*/
public Operation getQueryOperation();
/**
* Get the key relating to the event. In case of REGION_CLEAR and REGION_INVALIDATE operation, the
* key will be null.
*
* @return Object key.
*/
public Object getKey();
/**
* Get the new value of the modification. If there is no new value returns null, this will happen
* during delete operation. May throw <code>InvalidDeltaException</code>, if value is null and
* Delta Propagation is enabled.
*
* @return Object new/modified value.
*/
public Object getNewValue();
/**
* If an error occurred, return the Throwable, otherwise return null. If an error occurred, then
* this event will be passed to the <code>onError</code> method of the CqListener instead of the
* <code>onEvent</code> method.
*
* @return Throwable exception related to error.
*/
public Throwable getThrowable();
/**
* Get the delta modification. If there is no delta, returns null. New value may still be
* available.
*
* @return byte[] delta value.
* @since GemFire 6.5
*/
public byte[] getDeltaValue();
}