Add CommitInfo and return it from transactions

[mdsal.git] / common / mdsal-common-api / src / main / java / org / opendaylight / mdsal / common / api / EmptyCommitInfo.java

diff --git a/common/mdsal-common-api/src/main/java/org/opendaylight/mdsal/common/api/EmptyCommitInfo.java b/common/mdsal-common-api/src/main/java/org/opendaylight/mdsal/common/api/EmptyCommitInfo.java
new file mode 100644 (file)
index 0000000..8ec6635
--- /dev/null
+++ b/common/mdsal-common-api/src/main/java/org/opendaylight/mdsal/common/api/EmptyCommitInfo.java
@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2018 Pantheon Technologies, s.r.o. 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.common.api;
+
+import com.google.common.util.concurrent.FluentFuture;
+import com.google.common.util.concurrent.Futures;
+import org.eclipse.jdt.annotation.NonNullByDefault;
+
+/**
+ * Empty commit info singleton. Useful when {@link AsyncWriteTransaction#commit()} has nothing more to say.
+ *
+ * @author Robert Varga
+ */
+@NonNullByDefault
+final class EmptyCommitInfo implements CommitInfo {
+    static final CommitInfo INSTANCE = new EmptyCommitInfo();
+    static final FluentFuture<CommitInfo> FLUENT_INSTANCE = FluentFuture.from(Futures.immediateFuture(INSTANCE));
+
+    private EmptyCommitInfo() {
+        // Hidden
+    }
+}