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POFinding the race condition
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copied!<p>Can someone explain where the race condition is in this piece of code. My lecturer set it and I don't fully understand how to spot them yet, or say why the result that is given happens.</p> <pre><code>public class SlowRace { public static void main(String args []) throws Exception { MyThread.count = 0 ; MyThread thread1 = new MyThread() ; thread1.name = "A" ; MyThread thread2 = new MyThread() ; thread2.name = "B" ; thread1.start() ; thread2.start() ; thread2.join() ; thread1.join() ; System.out.println("MyThread.count = " + MyThread.count) ; } } class MyThread extends Thread { volatile static int count ; String name ; public void run() { for(int i = 0 ; i < 10 ; i++) { delay() ; int x = count ; System.out.println("Thread " + name + " read " + x) ; delay() ; count = x + 1; System.out.println("Thread " + name + " wrote " + (x + 1)) ; } } static void delay() { int delay = (int) (1000000000 * Math.random()) ; for(int i = 0 ; i < delay ; i++) {} } } </code></pre> <p>The result that gets returned:</p> <pre><code>Thread A read 0 Thread A wrote 1 Thread B read 0 Thread A read 1 Thread B wrote 1 Thread A wrote 2 Thread B read 2 Thread A read 2 Thread B wrote 3 Thread A wrote 3 Thread B read 3 Thread A read 3 Thread B wrote 4 Thread A wrote 4 Thread B read 4 Thread A read 4 Thread B wrote 5 Thread A wrote 5 Thread B read 5 Thread A read 5 Thread B wrote 6 Thread A wrote 6 Thread B read 6 Thread A read 6 Thread B wrote 7 Thread A wrote 7 Thread B read 7 Thread A read 7 Thread B wrote 8 Thread A wrote 8 Thread B read 8 Thread A read 8 Thread B wrote 9 Thread A wrote 9 Thread B read 9 Thread A read 9 Thread B wrote 10 Thread A wrote 10 Thread B read 10 Thread B wrote 11 MyThread.count = 11 </code></pre>

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