Bug 1073: Introduced Transaction Chain to DOMStore APIs.

[controller.git] / opendaylight / md-sal / sal-dom-spi / src / main / java / org / opendaylight / controller / sal / core / spi / data / DOMStoreTransactionChain.java

diff --git a/opendaylight/md-sal/sal-dom-spi/src/main/java/org/opendaylight/controller/sal/core/spi/data/DOMStoreTransactionChain.java b/opendaylight/md-sal/sal-dom-spi/src/main/java/org/opendaylight/controller/sal/core/spi/data/DOMStoreTransactionChain.java
new file mode 100644 (file)
index 0000000..5876c50
--- /dev/null
+++ b/opendaylight/md-sal/sal-dom-spi/src/main/java/org/opendaylight/controller/sal/core/spi/data/DOMStoreTransactionChain.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.sal.core.spi.data;
+
+/**
+ * A chain of transactions. Transactions in a chain need to be committed in
+ * sequence and each transaction must see the effects of previous transactions
+ * as if they happened. A chain makes no guarantees of atomicity, in fact
+ * transactions are committed as soon as possible.
+ *
+ *
+ */
+public interface DOMStoreTransactionChain extends DOMStoreTransactionFactory, AutoCloseable {
+
+    /**
+     * Create a new read only transaction which will continue the chain. The
+     * previous write transaction has to be either READY or CANCELLED.
+     *
+     * If previous write transaction was already commited to data store, new
+     * read-only transaction is same as obtained via {@link DOMStore#newReadOnlyTransaction()}
+     * and contains merged result of previous one and current state of data store.
+     *
+     * Otherwise read-only transaction presents isolated view as if previous read-write
+     * transaction was successful. State which was introduced by other transactions
+     * outside this transaction chain after creation of previous transaction is not visible.
+     *
+     * @return New transaction in the chain.
+     * @throws IllegalStateException
+     *             if the previous transaction was not READY or CANCELLED, or
+     *             if the chain has been closed.
+     */
+    @Override
+    public DOMStoreReadTransaction newReadOnlyTransaction();
+
+    /**
+     * Create a new read write transaction which will continue the chain. The
+     * previous read-write transaction has to be either COMMITED or CANCELLED.
+     *
+     * If previous write transaction was already commited to data store, new
+     * read-write transaction is same as obtained via {@link DOMStore#newReadWriteTransaction()}
+     * and contains merged result of previous one and current state of data store.
+     *
+     * Otherwise read-write transaction presents isolated view as if previous read-write
+     * transaction was successful. State which was introduced by other transactions
+     * outside this transaction chain after creation of previous transaction is not visible.
+     *
+     * @return New transaction in the chain.
+     * @throws IllegalStateException
+     *             if the previous transaction was not READY or CANCELLED, or
+     *             if the chain has been closed.
+     */
+    @Override
+    public DOMStoreReadWriteTransaction newReadWriteTransaction();
+
+    /**
+     * Create a new read write transaction which will continue the chain. The
+     * previous read-write transaction has to be either READY or CANCELLED.
+     *
+     *
+     * @return New transaction in the chain.
+     * @throws IllegalStateException
+     *             if the previous transaction was not READY or CANCELLED, or
+     *             if the chain has been closed.
+     */
+    @Override
+    public DOMStoreWriteTransaction newWriteOnlyTransaction();
+
+
+    /**
+     * Closes Transaction Chain.
+     *
+     * Close method of transaction chain does not guarantee that
+     * last alocated transaction is ready or was submitted.
+     *
+     * @throws IllegalStateException If any of the outstanding created transactions was not canceled or ready.
+     */
+    @Override
+    public void close();
+
+}