Return-Path: Mailing-List: contact commons-dev-help@jakarta.apache.org; run by ezmlm Delivered-To: mailing list commons-dev@jakarta.apache.org Received: (qmail 73009 invoked from network); 20 Aug 2003 07:53:40 -0000 Received: from rhenium.btinternet.com (194.73.73.93) by daedalus.apache.org with SMTP; 20 Aug 2003 07:53:39 -0000 Received: from host81-129-72-200.in-addr.btopenworld.com ([81.129.72.200] helo=oemcomputer) by rhenium.btinternet.com with smtp (Exim 3.22 #23) id 19pCWy-0007Tp-00 for commons-dev@jakarta.apache.org; Tue, 19 Aug 2003 20:52:36 +0100 Message-ID: <001801c3668b$b0afbba0$c8488151@oemcomputer> From: "Stephen Colebourne" To: "Jakarta Commons Developers List" References: Subject: Re: [collections] Questions.... Date: Tue, 19 Aug 2003 20:54:23 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4133.2400 X-MimeOLE: Produced By Microsoft MimeOLE V5.50.4133.2400 X-Spam-Rating: daedalus.apache.org 1.6.2 0/1000/N From: "Henri Yandell" > Firstly, SingletonIterator and SingletonListIterator seem quite similar. > Apart from the extra type of 'ListIterator', it appears that a > SingletonListIterator can do the job of a SingletonIterator in all jobs. > Could just remove SingleIterator. True, but somebody may only want the Iterator interface to be implemented. By having both we give the user the flexibility to choose. > Second question. What's ListIteratorWrapper useful for? > It seems to just let us throw a normal Iterator into something requiring > ListIterator-ness, except then it'll go ahead and throw exceptions on most > methods. So is it just an iterator that can get the previous element? Yep, it allows forwards and backwards movement through any iterator, not just list iterators. And no, I don't know why its useful. > Next. MultiMap has a remove(Object, Object) contract and therefore is not > a tag interface as the javadoc states. Actually MultiMap is a poor interface that probably should be changed. It is a difficult decision as we are not supposed to change interfaces, but it is perhaps unlikely that there are too many implementations of this one. See bugzilla. > The javadoc for a priority queue does not explain what a priority > queue is. Not sure if I remember either. > FastXxx classes say that they are not cross-platform, but in no way > discuss which platforms they are targetted at. This makes these classes > useless except to the authors. IIRC, nobody can ever answer this question. It may be a theoretical risk, or a real one. Who knows? Stephen