Support for a distributed counter
Change-Id: I346e9baa28556fac13e53771021f5f6fbcd75ac9
diff --git a/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncAtomicCounter.java b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncAtomicCounter.java
new file mode 100644
index 0000000..3cad25f
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onosproject/store/consistent/impl/DefaultAsyncAtomicCounter.java
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2015 Open Networking Laboratory
+ *
+ * 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.consistent.impl;
+
+import java.util.concurrent.CompletableFuture;
+import org.onosproject.store.service.AsyncAtomicCounter;
+import static com.google.common.base.Preconditions.*;
+
+/**
+ * Default implementation for a distributed AsyncAtomicCounter backed by
+ * partitioned Raft DB.
+ * <p>
+ * The initial value will be zero.
+ */
+public class DefaultAsyncAtomicCounter implements AsyncAtomicCounter {
+
+ private final String name;
+ private final Database database;
+
+ public DefaultAsyncAtomicCounter(String name, Database database) {
+ this.name = checkNotNull(name);
+ this.database = checkNotNull(database);
+ }
+
+ @Override
+ public CompletableFuture<Long> incrementAndGet() {
+ return database.nextValue(name);
+ }
+
+ @Override
+ public CompletableFuture<Long> get() {
+ return database.currentValue(name);
+ }
+}