diff options
Diffstat (limited to 'qpid/java/broker/src/main/java/org/apache/qpid/server/txn/TxnOp.java')
-rw-r--r-- | qpid/java/broker/src/main/java/org/apache/qpid/server/txn/TxnOp.java | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/qpid/java/broker/src/main/java/org/apache/qpid/server/txn/TxnOp.java b/qpid/java/broker/src/main/java/org/apache/qpid/server/txn/TxnOp.java new file mode 100644 index 0000000000..919c078cf0 --- /dev/null +++ b/qpid/java/broker/src/main/java/org/apache/qpid/server/txn/TxnOp.java @@ -0,0 +1,55 @@ +/* + * + * 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.qpid.server.txn; + +import org.apache.qpid.AMQException; +import org.apache.qpid.server.store.StoreContext; + +/** + * This provides the abstraction of an individual operation within a + * transaction. It is used by the TxnBuffer class. + */ +public interface TxnOp +{ + /** + * Do the part of the operation that updates persistent state + */ + public void prepare(StoreContext context) throws AMQException; + /** + * Complete the operation started by prepare. Can now update in + * memory state or make netork transfers. + */ + public void commit(StoreContext context) throws AMQException; + /** + * This is not the same as rollback. Unfortunately the use of an + * in memory reference count as a locking mechanism and a test for + * whether a message should be deleted means that as things are, + * handling an acknowledgement unavoidably alters both memory and + * persistent state on prepare. This is needed to 'compensate' or + * undo the in-memory change if the peristent update of later ops + * fails. + */ + public void undoPrepare(); + /** + * Rolls back the operation. + */ + public void rollback(StoreContext context) throws AMQException; +} |