java - Eclipse RCP IJob : Limit numer of concurrent executing jobs

Question

如何告诉 Eclipse RCP 作业管理同时运行最多 x 个作业？

编辑:

它通过使用答案中描述的自定义调度规则来工作。

切勿将相同的规则引用传递给多个作业，这一点很重要。

这是我使用的类:

公共(public)课JobMaster{

private class Listener implements IJobChangeListener {

    @Override
    public void aboutToRun(final IJobChangeEvent event) {
    }

    @Override
    public void awake(final IJobChangeEvent event) {
    }

    @Override
    public void done(final IJobChangeEvent event) {
        synchronized (JobMaster.this) {
            running--;
            System.err.println("now running " + running);
        }
    }

    @Override
    public void running(final IJobChangeEvent event) {
        synchronized (JobMaster.this) {
            running++;
            System.err.println("now running " + running);
        }
    }

    @Override
    public void scheduled(final IJobChangeEvent event) {

    }

    @Override
    public void sleeping(final IJobChangeEvent event) {
    }

}

private class MyRule implements ISchedulingRule {

    public MyRule() {

    }

    @Override
    public boolean contains(final ISchedulingRule rule) {
        if (rule == this) {
            return true;
        }
        return false;

    }

    @Override
    public boolean isConflicting(final ISchedulingRule rule) {
        synchronized (JobMaster.this) {
            if (rule == this) {
                return true;
            }
            if (rule instanceof MyRule) {
                return running >= maxRun;
            }
            return false;
        }
    }
}

private final Listener l = new Listener();

private final int maxRun;

private volatile int running = 0;

public JobMaster(final int maxRun) {
    this.maxRun = maxRun;

}

public synchronized void add(final Job j) {
    j.setRule(new MyRule());
    j.addJobChangeListener(l);
    j.schedule();
}

}

Answer 1

从 Eclipse Mars (4.5) 开始，可以使用作业组来限制并发线程的数量:

JobGroup jobGroup = new JobGroup("Job...", /* maxThreads*/ 10, /* seedJobsCount */ 100);

for (int ii = 0; ii < 100; ii++)
{            
    Job job = new Job("job name")
    {
        @Override
        protected IStatus run(IProgressMonitor monitor)
        {
            // do something
            return Status.OK_STATUS;
        }
    };
    job.setJobGroup(jobGroup);
    job.schedule();
}

jobGroup.join(10000, monitor);