/*
* 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;
/**
* A callback that is allowed to veto a transaction. Only one TransactionWriter can exist per cache,
* and only one TransactionWriter will be fired in the entire distributed system for each
* transaction.
*
* This writer can be used to update a backend data source before the GemFire cache is updated
* during commit. If the backend update fails, the implementer can throw a
* {@link TransactionWriterException} to veto the transaction.
*
* @see CacheTransactionManager#setWriter
* @since GemFire 6.5
*/
public interface TransactionWriter extends CacheCallback {
/**
* Called before the transaction has finished committing, but after conflict checking. Provides an
* opportunity for implementors to cause transaction abort by throwing a
* TransactionWriterException
*
* @param event the TransactionEvent
* @see CacheTransactionManager#commit
* @throws TransactionWriterException in the event that the transaction should be rolled back
*/
public void beforeCommit(TransactionEvent event) throws TransactionWriterException;
}