Add distributed lock primitive
Change-Id: I60f4581d5acb5fc9b9a21d4191874bb56348af58
diff --git a/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java b/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java
new file mode 100644
index 0000000..be35b5e
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/store/service/AsyncDistributedLock.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * Licensed 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.onosproject.store.service;
+
+import java.time.Duration;
+import java.util.Optional;
+import java.util.concurrent.CompletableFuture;
+
+import org.onosproject.store.primitives.DefaultDistributedLock;
+
+/**
+ * Asynchronous lock primitive.
+ */
+public interface AsyncDistributedLock extends DistributedPrimitive {
+ @Override
+ default Type primitiveType() {
+ return Type.LOCK;
+ }
+
+ /**
+ * Acquires the lock, blocking until it's available.
+ *
+ * @return future to be completed once the lock has been acquired
+ */
+ CompletableFuture<Version> lock();
+
+ /**
+ * Attempts to acquire the lock.
+ *
+ * @return future to be completed with a boolean indicating whether the lock was acquired
+ */
+ CompletableFuture<Optional<Version>> tryLock();
+
+ /**
+ * Attempts to acquire the lock for a specified amount of time.
+ *
+ * @param timeout the timeout after which to give up attempting to acquire the lock
+ * @return future to be completed with a boolean indicating whether the lock was acquired
+ */
+ CompletableFuture<Optional<Version>> tryLock(Duration timeout);
+
+ /**
+ * Unlocks the lock.
+ *
+ * @return future to be completed once the lock has been released
+ */
+ CompletableFuture<Void> unlock();
+
+ default DistributedLock asLock() {
+ return asLock(-1);
+ }
+
+ default DistributedLock asLock(long timeoutMillis) {
+ return new DefaultDistributedLock(this, timeoutMillis);
+ }
+}