控制只能开启一个rcp应用程序

    private boolean isAreadyRunning(){
        boolean locked=true;
        Location instanceLoc=Platform.getInstanceLocation();
        if(!instanceLoc.isSet()){
            try {
                instanceLoc.set(instanceLoc.getDefault(), false);//关键
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        try {
            if(instanceLoc.lock()){
                locked=false;           
            }else{
                locked=true;
                MessageDialog.openError(null,"Error","A XXX is running! can't start multiply appliction.");
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return locked;   
    }