CODEWITHSUNDEEP
javaeclipsemultithreading
john
john

Reputation: 707

How does Eclipse manage to stop threads so fast , if thread stopping is so awkward in Java?

I apologize in advance if this question sounds presumptuous. I'm fairly new to this. So here it goes . . .

I've been researching the "java thread stopping" issue for a while. I read many articles on stackoverflow, and most of them come to a conclusion that thread stopping is very awkward in java. Some good ways include:

  1. Using join (this answer got 87 upvotes) and wait until a thread finished.
  2. Set a volatile flag to signal the other threads. This answer got 113 upvotes
  3. Many recommend Thread.interrupt() and later check isInterrupted
  4. Some recommend using a high level API like ExecutorService. But that shutdownNow method does not give any guarantees, and counts on that isInterrupted boolean

But neither of the above methods allow an immediate thread stop. For example, if a program is running some SQL and waiting for an external database respond, then ALL of the above method will "humbly wait" until that SQL finishes. So the stopping is NOT immediate at all. Only when that SQL finishes (which may take hours), will the program check for isInterrupted or other flag, and then stop

Here is the punchline . . . I know Eclipse is written in java according to this stackoverflow answer. And whenever I click that red stop button , Eclipse will stop my application immediately. I presume it is NOT using Thread.stop since it's deprecated. But I it can't possible be using those method recommended on stackoverflow. How does Eclipse manage to stop threads so fast?

Upvotes: 1

Views: 714

Answers (1)

greg-449
greg-449

Reputation: 111217

When you run a Java program from within Eclipse a completely new JVM is created in a new Process to run the program. A process is not the same thing as a thread.

Within Eclipse the process is represented by the java.lang.Process class. Eclipse calls the destroy() method of Process when you stop the program.

So what Eclipse is using for this is nothing to do with threads.

Upvotes: 7

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