Re: Start thread in constructor

From:
Lew <lew@lewscanon.com>
Newsgroups:
comp.lang.java.programmer
Date:
Tue, 29 Jan 2008 08:42:38 -0500
Message-ID:
<UMWdnS9JtpPTsALanZ2dnUVZ_s7inZ2d@comcast.com>
tzvika.barenholz@gmail.com wrote:

On Jan 29, 9:04 am, Philipp <sicsic...@freesurf.ch> wrote:

Hello,
In the book "Java Threads" 3rd ed. by Oaks and Wong, we find the
following code example (p. 164):

public class FibonacciProducer implements Runable {
   // <snip> declaration of queue and thr as members
   public FibonacciProducer (BlockingQueue<Integer> q){
     queue = q;
     thr = new Thread(this);
     thr.start();
   }

   public void run(){
     // snip
   }

}

I read somewhere that it is bad practice to start a thread in the
constructor because this may publish the this pointer before the
constructor has returned. Is this not true in this case? Or should we
better code the above with a factory?

Thanks for your answers
Phil


It seems to me that you're right; the this reference should not be
published before construction is complete.


Agreed. Publishing the 'this' reference from the constructor via the Thread
was a mistake.

--
Lew

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