Re: Problem figuring out threading problem for SCJP

From:
Mark Space <markspace@sbc.global.net>
Newsgroups:
comp.lang.java.help
Date:
Tue, 19 Feb 2008 03:26:53 GMT
Message-ID:
<10suj.9798$0o7.3130@newssvr13.news.prodigy.net>
lielar wrote:

class MyThread extends Thread {
           String sa;

class Test {
           private static String sa = new String("Not Done");

I am not sure how to interpret this.


There are two objects named "sa". I'd interpret it as f'd up.

thread has the lock on the object sa (in the Test object). I'm not


The main thread does. The thread created from the MyThread object will
wait forever. The two never interact.

sure if it matters if its a String (immutable) object and that it is a
static object being synchronised.


I don't think it does. (In the general case, not because this program
doesn't really synchronize anything.)

If it is being synchronised in a different thread (main and t1), does
it matter?


It doesn't matter in this instance because two different objects are
used to synchronize two different threads. The locks and the threads
never interact.

This is a pretty basic exercise in "do you understand how to declare
variables" and has little to do with locks or threads.

Now lets see if I get totally proven wrong by someone ;) ....

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