Removed ReadWriteTransaction concept from APIs.
[mdsal.git] / binding / mdsal-binding-api / src / main / java / org / opendaylight / mdsal / binding / api / ReadOnlyTransaction.java
index ffde9ce823aebc969329175ab64c9b61e8a878bf..eb572dd27627809e1e891e769e224fab76807043 100644 (file)
@@ -8,16 +8,44 @@
 package org.opendaylight.mdsal.binding.api;
 
 import org.opendaylight.mdsal.common.api.AsyncReadOnlyTransaction;
-
+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 ReadOnlyTransaction extends ReadTransaction, AsyncReadOnlyTransaction<InstanceIdentifier<?>, DataObject> {
+public interface ReadOnlyTransaction extends AsyncReadOnlyTransaction<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);
 }