// concurrent/SynchronizedConstructor.java

// (c)2021 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

import java.util.concurrent.atomic.*;

class SyncConstructor implements HasID {

private final int id;

private static Object

constructorLock = new Object();

SyncConstructor(SharedArg sa) {

synchronized(constructorLock) {

id = sa.get();

}

}

@Override public int getID() { return id; }

}

public class SynchronizedConstructor {

public static void main(String[] args) {

Unsafe unsafe = new Unsafe();

IDChecker.test(() ->

new SyncConstructor(unsafe));

}

}

/* Output:

0

*/