Github user GJL commented on a diff in the pull request:
https://github.com/apache/flink/pull/5310#discussion_r163921620
--- Diff:
flink-runtime/src/test/java/org/apache/flink/runtime/concurrent/ManuallyTriggeredScheduledExecutor.java
---
@@ -0,0 +1,167 @@
+/*
+ * 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.flink.runtime.concurrent;
+
+import org.apache.flink.core.testutils.ManuallyTriggeredDirectExecutor;
+import org.apache.flink.util.Preconditions;
+
+import java.util.Iterator;
+import java.util.concurrent.Callable;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.Delayed;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ScheduledFuture;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+/**
+ * Simple {@link ScheduledExecutor} implementation for testing purposes.
+ */
+public class ManuallyTriggeredScheduledExecutor extends
ManuallyTriggeredDirectExecutor implements ScheduledExecutor {
+
+ private final ConcurrentLinkedQueue<ScheduledTask<?>> scheduledTasks =
new ConcurrentLinkedQueue<>();
+
+ @Override
+ public ScheduledFuture<?> schedule(Runnable command, long delay,
TimeUnit unit) {
+ return insertRunnable(command, false);
+ }
+
+ @Override
+ public <V> ScheduledFuture<V> schedule(Callable<V> callable, long
delay, TimeUnit unit) {
+ final ScheduledTask<V> scheduledTask = new
ScheduledTask<>(callable, false);
+
+ scheduledTasks.offer(scheduledTask);
+
+ return scheduledTask;
+ }
+
+ @Override
+ public ScheduledFuture<?> scheduleAtFixedRate(Runnable command, long
initialDelay, long period, TimeUnit unit) {
+ return insertRunnable(command, true);
+ }
+
+ @Override
+ public ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long
initialDelay, long delay, TimeUnit unit) {
+ return insertRunnable(command, true);
+ }
+
+ /**
+ * Triggers all registered tasks.
+ */
+ public void triggerScheduledTasks() {
+ final Iterator<ScheduledTask<?>> iterator =
scheduledTasks.iterator();
+
+ while (iterator.hasNext()) {
+ final ScheduledTask<?> scheduledTask = iterator.next();
+
+ scheduledTask.execute();
+
+ if (!scheduledTask.isPeriodic) {
+ iterator.remove();
+ }
+ }
+ }
+
+ private ScheduledFuture<?> insertRunnable(Runnable command, boolean
isPeriodic) {
+ final ScheduledTask<?> scheduledTask = new ScheduledTask<>(
+ () -> {
+ command.run();
+ return null;
+ },
+ isPeriodic);
+
+ scheduledTasks.offer(scheduledTask);
+
+ return scheduledTask;
+ }
+
+ private static final class ScheduledTask<T> implements
ScheduledFuture<T> {
+
+ private final Callable<T> callable;
+
+ private final boolean isPeriodic;
+
+ private final CompletableFuture<T> result;
+
+ private ScheduledTask(Callable<T> callable, boolean isPeriodic)
{
+ this.callable = Preconditions.checkNotNull(callable);
+ this.isPeriodic = isPeriodic;
+
+ this.result = new CompletableFuture<>();
+ }
+
+ public boolean isPeriodic() {
--- End diff --
nit: method is unused
---
