1 files changed, 165 insertions, 0 deletions
diff --git a/appc-oam/appc-oam-bundle/src/main/java/org/openecomp/appc/oam/util/AsyncTaskHelper.java b/appc-oam/appc-oam-bundle/src/main/java/org/openecomp/appc/oam/util/AsyncTaskHelper.java
new file mode 100644
index 000000000..ff28e995a
--- /dev/null
+++ b/appc-oam/appc-oam-bundle/src/main/java/org/openecomp/appc/oam/util/AsyncTaskHelper.java
@@ -0,0 +1,165 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP : APPC
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Copyright (C) 2017 Amdocs
+ * =============================================================================
+ * 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.
+ * 
+ * ECOMP is a trademark and service mark of AT&T Intellectual Property.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.appc.oam.util;
+
+import com.att.eelf.configuration.EELFLogger;
+import org.openecomp.appc.oam.AppcOam;
+import org.osgi.framework.Bundle;
+import org.osgi.framework.FrameworkUtil;
+
+import java.util.concurrent.Callable;
+import java.util.concurrent.Executors;
+import java.util.concurrent.Future;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+
+/**
+ * Utility class provides general async task related help.
+ */
+@SuppressWarnings("unchecked")
+public class AsyncTaskHelper {
+    final int MMODE_TASK_DELAY = 10000;
+    final int COMMON_INITIAL_DELAY = 0;
+    final int COMMON_INTERVAL = 1000;
+
+    private final EELFLogger logger;
+    private final ScheduledExecutorService scheduledExecutorService;
+    private final ThreadPoolExecutor bundleOperationService;
+
+    /** Reference to the Async task */
+    private volatile Future<?> backgroundOamTask;
+
+    /**
+     * Constructor
+     * @param eelfLogger of the logger
+     */
+    public AsyncTaskHelper(EELFLogger eelfLogger) {
+        logger = eelfLogger;
+
+        scheduledExecutorService = Executors.newSingleThreadScheduledExecutor(
+                (runnable) -> {
+                    Bundle bundle = FrameworkUtil.getBundle(AppcOam.class);
+                    return new Thread(runnable, bundle.getSymbolicName() + " scheduledExecutor");
+                }
+        );
+
+        bundleOperationService = new ThreadPoolExecutor(
+                0,
+                10,
+                10,
+                TimeUnit.SECONDS,
+                new LinkedBlockingQueue(),// BlockingQueue<Runnable> workQueue
+                (runnable) -> new Thread(runnable, "OAM bundler operation executor")//ThreadFactory
+        );
+    }
+
+    void addThreadsToPool() {
+        bundleOperationService.setCorePoolSize(bundleOperationService.getMaximumPoolSize());
+    }
+
+    void removeThreadsFromPoolWhenDone() {
+        bundleOperationService.setCorePoolSize(0);
+    }
+
+    /**
+     * Terminate the class <bS>ScheduledExecutorService</b>
+     */
+    public void close() {
+        logDebug("Start shutdown scheduleExcutorService.");
+        scheduledExecutorService.shutdown();
+        bundleOperationService.shutdown();
+        logDebug("Completed shutdown scheduleExcutorService.");
+    }
+
+    /**
+     * Get current async task refernce
+     * @return the class <b>backgroundOamTask</b>
+     */
+    public Future<?> getCurrentAsyncTask() {
+        return backgroundOamTask;
+    }
+
+    /**
+     * Schedule a service for async task with the passed in parameters
+     * @param rpc of the REST API call, decides how to schedule the service
+     * @param runnable of the to be scheduled service.
+     * @return the refernce of the scheduled task
+     */
+    public Future<?> scheduleAsyncTask(final AppcOam.RPC rpc, final Runnable runnable) {
+        int initialDelay, interval;
+        switch (rpc) {
+            case maintenance_mode:
+                initialDelay = interval =MMODE_TASK_DELAY;
+                break;
+            case start:
+            case stop:
+            case restart:
+                initialDelay = COMMON_INITIAL_DELAY;
+                interval = COMMON_INTERVAL;
+                break;
+            default:
+                // should not get here. Log it and return null
+                logDebug(String.format("Cannot scheudle task for unsupported RPC(%s).", rpc.name()));
+                return null;
+        }
+
+        // Always cancel existing  async task
+        if (backgroundOamTask != null) {
+            backgroundOamTask.cancel(true);
+        }
+        backgroundOamTask = scheduledExecutorService.scheduleWithFixedDelay(
+                runnable, initialDelay, interval, TimeUnit.MILLISECONDS);
+
+        return backgroundOamTask;
+    }
+
+    Future<?> submitBundleLcOperation(final Callable callable) {
+        return bundleOperationService.submit(callable);
+    }
+
+    /**
+     * Cancle a previously schedule task. If the task is the same as backgroundOamTask, set it to null.
+     * @param task to be canceled
+     */
+    public void cancelAsyncTask(Future<?> task) {
+        task.cancel(false);
+        if (task == backgroundOamTask) {
+            backgroundOamTask = null;
+        }
+    }
+
+    /**
+     * Genral debug log when debug logging level is enabled.
+     * @param message of the log message format
+     * @param args of the objects listed in the message format
+     */
+    private void logDebug(String message, Object... args) {
+        if (logger.isDebugEnabled()) {
+            logger.debug(String.format(message, args));
+        }
+    }
+}