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POUse and flow of Static statements in Singleton Program
 

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    <p>I know there are lot of questions on Singleton pattern. But here what I would like to know about the output which might also cover how "static" works in Java.</p> <pre><code>public class Singleton { private static Singleton currentSingleton = new Singleton(); public static Singleton getSingleton() { return currentSingleton; } private Singleton() { System.out.println("Singleton private constructor..."); } public static void main(String[] args) { System.out.println("Main method..."); } </code></pre> <p>    }</p> <p>This is the output from running the code...</p> <blockquote> <p>Singleton private constructor... <br> Main method...</p> </blockquote> <p>When I debugged this code, control went first to line <code>System.out.println("Singleton private constructor...")</code> and prints. (private static variable currentSingleton is still null at this point) <br> Then it goes to line <br> <code>private static Singleton currentSingleton = new Singleton();</code> and then initializes the private variable. Then at last, it goes to main() method and prints.</p> <p>My Questions are:</p> <ol> <li>Why it first prints "Singleton private constructor..." which is in private constructor. I thought control should first go to main() method since it is the entry point. Also I am not creating any instance anywhere (except in variable initialization).</li> <li>Later it goes to static variable instantiation line (currentSingleton=null at this point) <br> <code>private static Singleton currentSingleton = new Singleton();</code> Though currentSingleton gets a value here, why constructor is not called again?</li> </ol> <p>Mainly I want to know the flow of control of this program.</p>
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