Renamed Data(ReadOnly|WriteOnly) to DataTree(Read|Write)

[mdsal.git] / binding / mdsal-binding-api / src / main / java / org / opendaylight / mdsal / binding / api / ReadTransaction.java

diff --git a/binding/mdsal-binding-api/src/main/java/org/opendaylight/mdsal/binding/api/ReadTransaction.java b/binding/mdsal-binding-api/src/main/java/org/opendaylight/mdsal/binding/api/ReadTransaction.java
new file mode 100644 (file)
index 0000000..ee40cdd
--- /dev/null
+++ b/binding/mdsal-binding-api/src/main/java/org/opendaylight/mdsal/binding/api/ReadTransaction.java
@@ -0,0 +1,51 @@
+/*
+ * 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.mdsal.binding.api;
+
+import org.opendaylight.mdsal.common.api.AsyncReadTransaction;
+import org.opendaylight.mdsal.common.api.LogicalDatastoreType;
+import org.opendaylight.mdsal.common.api.ReadFailedException;
+import org.opendaylight.yangtools.yang.binding.DataObject;
+import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
+
+import com.google.common.base.Optional;
+import com.google.common.util.concurrent.CheckedFuture;
+
+/**
+ * A transaction that provides a stateful read-only view of the data tree.
+ * <p>
+ * For more information on usage and examples, please see the documentation in
+ *  {@link org.opendaylight.mdsal.common.api.AsyncReadTransaction}.
+ */
+public interface ReadTransaction extends AsyncReadTransaction<InstanceIdentifier<?>, DataObject> {
+
+    /**
+     * Reads data from the provided logical data store located at the provided path.
+     *<p>
+     * If the target is a subtree, then the whole subtree is read (and will be
+     * accessible from the returned data object).
+     *
+     * @param store
+     *            Logical data store from which read should occur.
+     * @param path
+     *            Path which uniquely identifies subtree which client want to
+     *            read
+     * @return a CheckFuture containing the result of the read. The Future blocks until the
+     *         commit operation is complete. Once complete:
+     *         <ul>
+     *         <li>If the data at the supplied path exists, the Future returns an Optional object
+     *         containing the data.</li>
+     *         <li>If the data at the supplied path does not exist, the Future returns
+     *         Optional#absent().</li>
+     *         <li>If the read of the data fails, the Future will fail with a
+     *         {@link ReadFailedException} or an exception derived from ReadFailedException.</li>
+     *         </ul>
+     */
+    <T extends DataObject> CheckedFuture<Optional<T>,ReadFailedException> read(
+            LogicalDatastoreType store, InstanceIdentifier<T> path);
+}