Mailing-List: contact dev-help@harmony.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@harmony.apache.org
Received-SPF: pass (herse.apache.org: domain of wuyuehao@gmail.com designates
 66.249.82.233 as permitted sender)
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
        s=beta; d=gmail.com;
        h=received:message-id:date:from:to:subject:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references;
        b=QFNOkJ61j0QVdQAuXmSJXTvHZV/OItcpsDFS6K8yzk9B/Mqnkc4Ysddqea/0Yy5wXPd7Reu+3HHf6JPudT0d81nGXpeKN+Pi9uFPTNr6FMzqjwh17hjpRnfjR1jxLs9H3vEvj83N6PouuLnQc+hg4SL/IU6NVuZm7ksMMCyssvI=
Message-ID: <211709bc0612041804o7cf32fc8g2936b28252e8f8ed@mail.gmail.com>
Date: Tue, 5 Dec 2006 10:04:19 +0800
From: "Tony Wu" <wuyuehao@gmail.com>
To: dev@harmony.apache.org
Subject: Re: svn commit: r480871 - in
 /harmony/enhanced/classlib/trunk/modules/luni/src:
 main/java/java/lang/ProcessBuilder.java
 main/java/org/apache/harmony/luni/platform/Environment.java
 test/java/org/apache/harmony/luni/tests/java/lang/SystemTest.java
In-Reply-To: <3b3f27c60612041754j29946ccfp9cc69a36d6dddb53@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
References: <20061130081959.0B5381A9846@eris.apache.org>
	 <4570467F.5010207@pobox.com>
	 <211709bc0612032250u15c98f97k6a4f103056c9476@mail.gmail.com>
	 <f944d83d0612040001j5dd61438y7e3436ccf5bf4d94@mail.gmail.com>
	 <45742354.20203@pobox.com>
	 <3b3f27c60612041754j29946ccfp9cc69a36d6dddb53@mail.gmail.com>

And AFAIK, the value is generated according to the field of the class.
So is it correct that the generated SID will be 1L if no field
present?

On 12/5/06, Nathan Beyer <nbeyer@gmail.com> wrote:
> That's not a magic value. A serial version UID of 1 is considered, by
> some, a default value. I know that within a Eclipse, you can either
> generate a value (ala serialver tool) or insert the default value
> (1L).
>
> The serial version UID is an arbitrary value that's meant to be a
> marker for a given class if two serialized objects are compatible.
> Using small iterative values (1, 2, etc) is really no different than
> using a complex weighted calculation that changes when the class
> changes. As long as the number changes or doesn't change for a given
> class, then the compatability or incompatibility, respectively, is
> deterministic.
>
> -Nathan
>
> On 12/4/06, Geir Magnusson Jr. <geir@pobox.com> wrote:
> >
> >
> > Alexey Varlamov wrote:
> > > 2006/12/4, Tony Wu <wuyuehao@gmail.com>:
> > >> This class will never be serialized. I think the meanless variable
> > >> here is created to avoid compiler warining.
> > >
> > > How about using @SupressWarnings("serial")? It is more readable IMO.
> >
> > Thank you.  I didn't know what to suggest, but a magic value was
> > misleading w/o a comment...
> >
> > geir
> >
> > >
> > >>
> > >> On 12/1/06, Geir Magnusson Jr. <geir@pobox.com> wrote:
> > >> >
> > >> >
> > >> > liangyx@apache.org wrote:
> > >> > > Author: liangyx
> > >> > > Date: Thu Nov 30 00:19:55 2006
> > >> > > New Revision: 480871
> > >> > >
> > >> > > URL: http://svn.apache.org/viewvc?view=rev&rev=480871
> > >> > > Log:
> > >> > > Apply patch for HARMONY-2356 ([classlib][luni]The Map from
> > >> System.getEnv should throw NullPointerException while get(null) and is
> > >> not modifiable.)
> > >> > >
> > >> > > Modified:
> > >> > >
> > >> harmony/enhanced/classlib/trunk/modules/luni/src/main/java/java/lang/ProcessBuilder.java
> > >>
> > >> > >
> > >> harmony/enhanced/classlib/trunk/modules/luni/src/main/java/org/apache/harmony/luni/platform/Environment.java
> > >>
> > >> > >
> > >> harmony/enhanced/classlib/trunk/modules/luni/src/test/java/org/apache/harmony/luni/tests/java/lang/SystemTest.java
> > >>
> > >> > >
> > >> >
> > >> > > +
> > >> > > +    public static class EnvironmentMap extends HashMap<String,
> > >> String> {
> > >> > > +
> > >> > > +        private static final long serialVersionUID = 1L;
> > >> > > +
> > >> > > +        public EnvironmentMap() {
> > >> > > +            super();
> > >> > > +        }
> > >> > > +
> > >> > > +        public EnvironmentMap(Map<String, String> map) {
> > >> > > +            super(map);
> > >> > > +        }
> > >> > > +
> > >> > > +        public boolean containsKey(Object key) {
> > >> > > +            checkParam(key);
> > >> > > +            return super.containsKey(key);
> > >> > > +        }
> > >> >
> > >> >
> > >> >
> > >> > I'm curious - why set the ServialVersionUID to 1?
> > >> >
> > >> > geir
> > >> >
> > >>
> > >>
> > >> --
> > >> Tony Wu
> > >> China Software Development Lab, IBM
> > >>
> >
>


-- 
Tony Wu
China Software Development Lab, IBM