RCP产品异常：Job found still running after platform shutdown. Jobs should be canceled

RCP 工程打开时异常信息：

Job found still running after platform shutdown.  Jobs should be canceled by the plugin that scheduled them during shutdown: ... ...
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分析发现时程序用的一个UIJob，在workbench非正常关闭时，UIJob还在运行，于是就有了上面的异常，替换成WorkbenchJob，就会正常。
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WorkbenchJob时一个专门的UIJob类，和UIJob的主要区别：在允许作业被调度和运行前，WorkbenchJob检测Workbench是否正在运行。

WorkbenchJob它使用作业更改监听器来确保：当作业已经完成时，在WorkbenchJob中包含的preformDone方法也被调用。

WorkbenchJob是UIJob的一种更安全的形式。WorkbenchJob会自己检测Workbench是否在运行，当Workbench关闭时，WorkbenchJob强制终止用户界面的更新。

WorkbenchJob源码贴一下：（关键是本身对PlatformUI.isWorkbenchRunning()的调用）

public abstract class WorkbenchJob extends UIJob {

    public WorkbenchJob(Display jobDisplay, String name) {
        super(jobDisplay, name);
        addDefaultJobChangeListener();
    }

    public WorkbenchJob(String name) {
        super(name);
        addDefaultJobChangeListener();
    }


    private void addDefaultJobChangeListener() {
        addJobChangeListener(new JobChangeAdapter() {
            public void done(IJobChangeEvent event) {
                //Abort if it is not running
                if (!PlatformUI.isWorkbenchRunning()) {
                    return;
                 }
                if (event.getResult().getCode() == IStatus.OK) {
                      performDone(event);
                
            }
        });
    }

    public void performDone(IJobChangeEvent event) {
        //Do nothing by default.
    }

    public boolean shouldSchedule() {
        return super.shouldSchedule() && PlatformUI.isWorkbenchRunning();
    }

    public boolean shouldRun() {
        return super.shouldRun() && PlatformUI.isWorkbenchRunning();
    }

}