1 files changed, 55 insertions, 0 deletions
diff --git a/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/states/DatanodeState.java b/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/states/DatanodeState.java
new file mode 100644
index 0000000000..75142afd10
--- /dev/null
+++ b/hadoop-hdds/container-service/src/main/java/org/apache/hadoop/ozone/container/common/states/DatanodeState.java
@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.apache.hadoop.ozone.container.common.states;
+
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * State Interface that allows tasks to maintain states.
+ */
+public interface DatanodeState<T> {
+  /**
+   * Called before entering this state.
+   */
+  void onEnter();
+
+  /**
+   * Called After exiting this state.
+   */
+  void onExit();
+
+  /**
+   * Executes one or more tasks that is needed by this state.
+   *
+   * @param executor -  ExecutorService
+   */
+  void execute(ExecutorService executor);
+
+  /**
+   * Wait for execute to finish.
+   *
+   * @param time - Time
+   * @param timeUnit - Unit of time.
+   */
+  T await(long time, TimeUnit timeUnit)
+      throws InterruptedException, ExecutionException, TimeoutException;
+
+}