线程饥饿死锁在代码中发生了吗？

问题描述

 c>  c>  c>   c>  c>  c>  两个任务提交到 exec 。首先是 LoadFileTask（header.html），第二个是 LoadFileTask（footer.html）。但是因为ExecutorService  exec 通过代码 Executors.newSingleThreadExecutor（）; 获得 使用单个工作线程关闭一个无界的queueThread ，并且线程已经分配给RenderPageTask，所以 LoadFileTask（header.html）和 LoadFileTask html）将被排队到无界队列，等待由线程执行。 
 
  RenderPageTask 正在返回一个字符串，其中包含 LoadFileTask（header.html）和 LoadFileTask（footer.html）的输出。在这三个部分中， RenderPageTask 成功获得了页。但是其他两个部分只有在两个任务都由由 ExecutorService 分配的单个线程执行之后才能获得。只有 call（）方法 RenderPageTask 返回时，线程才会自由。但调用方法 RenderPageTask 只会在后返回LoadFileTask（header.html）和返回LoadFileTask（footer.html）。因此，不要让执行 LoadFileTask 导致 Starvation 。每个任务等待其他任务完成导致 DeadLock  
 
 
 
我希望这清楚为什么线程饥饿死锁正在上面的代码中发生。 
 
 
Task is submitted to exec for Rendering the page via Callable implemented class RenderPageTask.
exec started the RenderPageTask in separate Thread , the only Thread that would execute other tasks submitted to exec sequentially .
Inside call() method of RenderPageTask two more tasks are submitted to exec . First is LoadFileTask("header.html") and second is LoadFileTask("footer.html"). But since the the ExecutorService exec obtained via code Executors.newSingleThreadExecutor(); as mentioned here uses a single worker thread operating off an unbounded queueThread and the thread is already allocated to RenderPageTask , So LoadFileTask("header.html") and  LoadFileTask("footer.html") will be en queued to the unbounded queue waiting for there turn to be executed by that Thread.
RenderPageTask is returning a String containing the concatenation of output of   LoadFileTask("header.html") , body of page and output of LoadFileTask("footer.html"). Out of these three parts page is obtained successfully by RenderPageTask . But other two parts can only be obtained after both tasks are executed by the single Thread allocated by ExecutorService . And Thread will be free only after call() method of RenderPageTask returns . But call method of RenderPageTask will return only after LoadFileTask("header.html") and LoadFileTask("footer.html") is returned. So Not letting LoadFileTask to execute is leading to Starvation . And each task waiting for other task for completion is leading to DeadLock

I hope this makes clear of why thread starvation deadlock is occurring in above code.
                        
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