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POJava : static fields behaviour in different executions
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copied!<p>I have this class : </p> <pre><code>package scripts; public class TestStatic { public static void main(String[] args) { new IncrA().incrStatic(); } } class Static { public static int CPT = 0; } class IncrA{ public void incrStatic(){ for (int i:Range.ints(0,100)){ System.out.println("Now with "+this.toString()+" : Static.CPT="+Static.CPT); Static.CPT++; try{ Thread.sleep(100); } catch(Exception e){ e.printStackTrace(); } } System.out.println("Finally for execution of "+this.toString()+" : Static.CPT="+Static.CPT); } } </code></pre> <p>Now I run the class TestStatic in java from the command line, twice.</p> <pre><code>javaw -cp ... scripts.TestStatic > 1.txt javaw -cp ... scripts.TestStatic > 2.txt </code></pre> <p>I was expecting that the first and second executions would interfere, and get a value for Static.CPT == 200 in the end, because I thought the JVM would load only once the Static class. It seems it is not the case. Although I like it, I wonder if this example of mine is enough to conclude that the JVM completely separates exectutions. Actually, when I read my output, the hashCode for my IncrA object is often the same in both executions :</p> <p>From 1.txt :</p> <pre><code>... Now with scripts.IncrA@19f953d : Static.CPT=72 Now with scripts.IncrA@19f953d : Static.CPT=73 Now with scripts.IncrA@19f953d : Static.CPT=74 Now with scripts.IncrA@19f953d : Static.CPT=75 ... </code></pre> <p>From 2.txt : </p> <pre><code>... Now with scripts.IncrA@19f953d : Static.CPT=72 Now with scripts.IncrA@19f953d : Static.CPT=73 Now with scripts.IncrA@19f953d : Static.CPT=74 Now with scripts.IncrA@19f953d : Static.CPT=75 ... </code></pre> <p>The <code>@19f953d</code> is shared among the two executions. </p> <p>I googled for deep explanations on static keyword but did not find anything about these issues. Could someone explain or give a nice pointer ?</p>

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