Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.albasani.net!.POSTED!not-for-mail
From: Lew <noone@lewscanon.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: Refactoring discovery
Date: Wed, 30 Mar 2011 23:58:02 -0400
Organization: albasani.net
Lines: 30
Message-ID: <in0u43$8ib$1@news.albasani.net>
References: <kbgoo6dfrkh58r3ogel9nb6rekrs258it2@4ax.com> <imi0cq$ah4$1@dont-email.me> <imjjus$2cj$1@lust.ihug.co.nz> <e7Mkp.1468$0s5.314@newsfe17.iad> <in07ga$g5q$1@dont-email.me>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: news.albasani.net tFzLjd2i4Rz53Mfpqk3bjh10Xfuhz4I4IDanbbTMkK7pDIqqejeK3CArKM0oCp4mvXycnF2dwNVpm7kFq3PROg==
NNTP-Posting-Date: Thu, 31 Mar 2011 03:57:56 +0000 (UTC)
Injection-Info: news.albasani.net; logging-data="sZ4o+jTespt4qZ+DoZIbAj01rr3f0Q0Puk/ngKhV6Xq/fH0MfUmcI3SPHyxgLtSspriC+jU1DbVRPSfeUgtr4RZi/xYH6JG0NfZxHDC03unOTMKDZD9mLkC9jes41twb"; mail-complaints-to="abuse@albasani.net"
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.14) Gecko/20110223 Thunderbird/3.1.8
In-Reply-To: <in07ga$g5q$1@dont-email.me>
Cancel-Lock: sha1:DBibAtanWYlHiY8dMbr0G1+hRko=
Xref: x330-a1.tempe.blueboxinc.net comp.lang.java.programmer:2631

Joshua Cranmer wrote:
> Well, another way to implement this is:
>
> public boolean hasKey(Y y) {
>   LocPtr ptr = getWhereToInsert(y);
>   this.cachedPtr = ptr;
>   return ptr.valid();
> }
>
> public void addPair(Y y, Object obj) {
>   LocPtr ptr;
>   if (cachedPtr && cachedPtr.y == y)

Umm, that won't compile in Java.

>     ptr = cachedPtr;
>   else
>     ptr = getWhereToInsert(y);
>   ptr.insert(obj);
> }
>
> Which pretty much gets you the "benefit" of combining them into one single
> operation without needing to provide all of the back-level predicate code
> operations (set-if-present, set-if-not-present, etc.)

Unless you're in multi-threaded land.  In that case, don't think tacking 
'synchronized' onto your method definitions will help.

-- 
Lew