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Java puzzle System.exit and locks

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Java puzzle System.exit and locks

· Java Zone
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What every Java engineer should know about microservices: Reactive Microservices Architecture.  Brought to you in partnership with Lightbend.

When you call System.exit() it will stop the execution of the thread at that point and not call any finally blocks.
private static final Object lock = new Object();

public static void main(String... args) {
    Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() {
        @Override
        public void run() {
            System.out.println("Locking");
            synchronized (lock) {
                System.out.println("Locked");
            }
        }
    }));
    synchronized (lock) {
        System.exit(0);
    }
}
What does this program print?

Replace System.exit(0) with Thread.currentThread().stop() and run again for comparison.

 

From http://vanillajava.blogspot.com/2011/12/java-puzzle-systemexit-and-locks.html

Microservices for Java, explained. Revitalize your legacy systems (and your career) with Reactive Microservices Architecture, a free O'Reilly book. Brought to you in partnership with Lightbend.

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