Re: List or Iterator

From:
"Mike Schilling" <mscottschilling@hotmail.com>
Newsgroups:
comp.lang.java.programmer
Date:
Sat, 25 Jul 2009 11:27:58 -0700
Message-ID:
<h4fj8g$gv4$1@news.eternal-september.org>
Lew wrote:

Roedy Green wrote:

The advantage of an Iterator is the client can't modify your
original
list.


Unless it uses
<http://java.sun.com/javase/6/docs/api/java/util/Iterator.html#remove()

Iterator is more general. You could for example later modify the
producer to fetch records from a sequential file, without having to
change the client.

The general rule is avoid giving your client any more power than
they
absolutely need to get the job done.


I guess you're focusing on returning an Iterator, as opposed to
passing one in as an argument.

In the argument scenario you need more work to avoid the concurrent
modification issues other respondents have mentioned.

Even in the return scenario, you might get more joy returning an
Iterable than an Iterator.


Like most of these questions, it depends on what you're really doing.
If you're passing something that can be iterated over more than once
(e.g. the children of a DOM Node), pass Iterable. If it can only be
iterated over once and then it's gone (e.g. a series of SAX events
generated from an InputStream), pass Iterator.

You can probably tell that I've been doing a lot of XML programming
lately.

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