本文整理汇总了Java中java.util.concurrent.ConcurrentMap.Entry方法的典型用法代码示例。如果您正苦于以下问题:Java ConcurrentMap.Entry方法的具体用法?Java ConcurrentMap.Entry怎么用?Java ConcurrentMap.Entry使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类java.util.concurrent.ConcurrentMap
的用法示例。
在下文中一共展示了ConcurrentMap.Entry方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的Java代码示例。
示例1: maybeScheduleASpeculation
import java.util.concurrent.ConcurrentMap; //导入方法依赖的package包/类
private int maybeScheduleASpeculation(TaskType type) {
int successes = 0;
long now = clock.getTime();
ConcurrentMap<JobId, AtomicInteger> containerNeeds
= type == TaskType.MAP ? mapContainerNeeds : reduceContainerNeeds;
for (ConcurrentMap.Entry<JobId, AtomicInteger> jobEntry : containerNeeds.entrySet()) {
// This race conditon is okay. If we skip a speculation attempt we
// should have tried because the event that lowers the number of
// containers needed to zero hasn't come through, it will next time.
// Also, if we miss the fact that the number of containers needed was
// zero but increased due to a failure it's not too bad to launch one
// container prematurely.
if (jobEntry.getValue().get() > 0) {
continue;
}
int numberSpeculationsAlready = 0;
int numberRunningTasks = 0;
// loop through the tasks of the kind
Job job = context.getJob(jobEntry.getKey());
Map<TaskId, Task> tasks = job.getTasks(type);
int numberAllowedSpeculativeTasks
= (int) Math.max(minimumAllowedSpeculativeTasks,
proportionTotalTasksSpeculatable * tasks.size());
TaskId bestTaskID = null;
long bestSpeculationValue = -1L;
// this loop is potentially pricey.
// TODO track the tasks that are potentially worth looking at
for (Map.Entry<TaskId, Task> taskEntry : tasks.entrySet()) {
long mySpeculationValue = speculationValue(taskEntry.getKey(), now);
if (mySpeculationValue == ALREADY_SPECULATING) {
++numberSpeculationsAlready;
}
if (mySpeculationValue != NOT_RUNNING) {
++numberRunningTasks;
}
if (mySpeculationValue > bestSpeculationValue) {
bestTaskID = taskEntry.getKey();
bestSpeculationValue = mySpeculationValue;
}
}
numberAllowedSpeculativeTasks
= (int) Math.max(numberAllowedSpeculativeTasks,
proportionRunningTasksSpeculatable * numberRunningTasks);
// If we found a speculation target, fire it off
if (bestTaskID != null
&& numberAllowedSpeculativeTasks > numberSpeculationsAlready) {
addSpeculativeAttempt(bestTaskID);
++successes;
}
}
return successes;
}