Java tutorial
/** * 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.apache.aurora.scheduler.async; import java.util.Queue; import java.util.Set; import com.google.common.base.Optional; import com.google.common.collect.ImmutableSet; import com.google.common.collect.Lists; import org.apache.aurora.scheduler.async.TaskGroups.GroupKey; /** * A group of task IDs that are eligible for scheduling, but may be waiting for a backoff to expire. */ class TaskGroup { private final GroupKey key; private long penaltyMs; private final Queue<String> tasks; TaskGroup(GroupKey key, String initialTaskId) { this.key = key; this.penaltyMs = 0; this.tasks = Lists.newLinkedList(); this.tasks.add(initialTaskId); } synchronized GroupKey getKey() { return key; } synchronized Optional<String> peek() { return Optional.fromNullable(tasks.peek()); } synchronized boolean hasMore() { return !tasks.isEmpty(); } synchronized void remove(String taskId) { tasks.remove(taskId); } synchronized void offer(String taskId) { tasks.offer(taskId); } synchronized void setPenaltyMs(long penaltyMs) { this.penaltyMs = penaltyMs; } // Begin methods used for debug interfaces. public synchronized String getName() { return key.toString(); } public synchronized Set<String> getTaskIds() { return ImmutableSet.copyOf(tasks); } public synchronized long getPenaltyMs() { return penaltyMs; } }