How to kill a Thread?

Hello,
My question is simple how to kill a thread.
The background is a call to a method in a third party API, crawler4j, that locks the entire program.
The design of crawler4j is "You should stop it when you think it's enough (ctrl+c)" but as I use it only as a step in a larger program I want to stop it programmatically and not by "ctrl+c" as they have designed the API.
This is the locking callcontroller.start(MyCrawler.class, numberOfCrawlers);So I made a thread public class MyCrawlController extends Thread {
public void run(){
controller.start(MyCrawler.class, numberOfCrawlers);
}And in my main method
MyCrawlController mCC = new MyCrawlController();
mCC.start();
Thread.sleep(180000);
//Here I want to kill the mCC and all it's threadsOne problem is that my program never terminates. Probably due too the JVM not realizing that I don't want it to count mCC and it's spawned threads as alive. Any idea on how to solve this. For now I can only exit the program with System.exit(0); and I don't want that. So I need a way to stop the mCC's threads and get the JVM not to count them. Any idea on how to solve this. Even better if they can be taken by the GC.

Farmor wrote:
Thanks for the answer.
I came to think about daemons and solved the problem with mCC.setDaemon(true);Really stupid that one has to do several programs and tie them together only to kill a thread.
As I only do this for other learning purposes and won't use this code or program after this week I will modify crawler4j, open source, and make myself a custom good method that will terminate itself and return to the main method properly.There are some fairly difficult problems with a number of aspects of concurrency if you forcibly stop threads, which is why Thread.stop() and related methods have long been deprecated.
It's a pity that Java can't respond to kill signals (like Ctrl-C) in a tidy way. I think they're all tied up with some of the JVMs internal processes.
In general people wind up using sockets instead of signals.

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How to kill thread

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Thread.interrupt()
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Thre
ad.html#interrupt() is not about killing or stopping
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There is no way to kill a thread. As been said
above, the thread should be designed to accept
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The interrupt() was created by sun as a solution sun came up for the problems of thread stop(), it should be the cannonical way to stop a thread.
The problem with having your own mechanism of interrupting a thread is that you should have a method to interrupt a thread execution and a flag that should be checked from inside your thread or runnable code to see if it should stop and if so, do it cleanly. The problem with this aproach is that if the thread is sleeping or in some blocked state, calling your own interruption framework is inefective, as it could never get a chance to run the code.
To solve that, sun privides us with the method( interrupt() ) and the flag ( Thread.interrupted() ) with the advantage that on calling it, it guarantees you that it would take effect even if the thread is in a blocked state.
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May the code be with you.

Killing a Thread

In recent versions of the JDK they deprecated the stop() and destroy() methods. They did so because those methods can kill a thread in a "dirty" way. The replacement approach is to have a while(isRunning){} loop in the run() method and to set isRunning to false via a call to another method.
I have a scenario that can be described as follows (taking some liberties with syntax):
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Here, although the interface is standard, the job is one of many possible applications written by other people and without access to their source code. The JobInterface is already defined and there are many applications already in production that use it - in other ways we can't expect to change the code of the reflected jobs. Further, setting isRunning to false while the job is executing its execute() method (possibly for hours) isn't going to help.
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bmelloni wrote:
I only need the forced thread stop for those jobs that cannot be modified to comply with the above. At that point whatever consequences there are for those jobs will have to be accepted. If resources (i.e.: database) are left in messed up states... tough. It will have to be handled then (and maybe it will give incentive to make those black-box jobs compliant).I doubt it. Unless someone quite high-up is informed, these things are often shelved until something breaks. My suggestion would be to put your (our?) concerns in writing, and make sure you get a reply in kind from your management before you do anything. Once the finger-pointing starts, it's usually the sharp end that suffers.
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In other words, don't worry... we are not stupid.I don't think anyone said stupid...Naive, maybe.
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Selena wrote:
Hi.
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where the memory usage would rapidly increase from ~ 15Mb to the max heap size.
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the threads in the specific queue, which doesn't help me here.
Thanks.
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How can I kill a thread.

I have read the many threads about killing a thread but they dont answer the question I need to know.
In class#1 I have the following snipet of code:
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Thanks in advanceMessage was edited by:
Storm897

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