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From: Eric Sosman <esosman@ieee-dot-org.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: Threads and statics
Date: Thu, 07 Apr 2011 21:14:49 -0400
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On 4/7/2011 8:34 AM, Dirk Bruere at NeoPax wrote:
> Is there a problem with multiple threads using the same static method of
> a class?

     No.  There's also no problem with multiple threads using the
same instance method of a class, or even of a particular instance.

     What matters is whether the methods use the same data.  Static
or instance, it's the data-sharing that requires synchronization or
other special handling -- conversely, it's the non-sharing that
requires no care at all.

     Advice that I found illuminating when first learning about
threading: Don't think about the code, think instead about the data
the code manipulates (more generally, about the "state" the code
manipulates).  Make sure the data is always seen in a consistent
state, except perhaps by the *one* thread that's in the act of
changing it; then you'll have a correct program.  (It might not be
the fastest possible program -- that's where the hard parts come
in -- but at least it won't have race conditions.)

-- 
Eric Sosman
esosman@ieee-dot-org.invalid