Re: Opinion poll: for loop vs while loop with Iterators.

From:
"Karl Uppiano" <karl.uppiano@verizon.net>
Newsgroups:
comp.lang.java.programmer
Date:
Thu, 21 Dec 2006 20:54:36 GMT
Message-ID:
<gwCih.6918$Pq4.709@trndny08>
"Daniel Pitts" <googlegroupie@coloraura.com> wrote in message
news:1166733645.346823.323820@73g2000cwn.googlegroups.com...

Java 1.5 finaly gave us an elegant for each construct, but for-each
lacks the ability to manipulate the underlying Iterable structure.

Generally, the way to do this is (in pseudo-code:)

Obtain the iterator.
L: Check if it has a next element
get the next element
process the element.
repeat from L

This can be coded in Java a few ways.
// For method:
for (Iterator<E> iterator = iterable.iterator(); iterator.hasNext(); )
{
  E e = iterator.next();
  if (shouldRemove(e)) {
     iterator.remove(e);
  }
}

// vs
// While method:
Iterator<E> iterator = iterable.iterator();
while (iterator.hasNext()) {
  E e = iterator.next();
  if (shouldRemove(e)) {
     iterator.remove(e);
  }
}

Both approaches have their pros and cons, but I'm interested to see
what people think.

I'll post my opinion later.


I tend to use the while pattern for no particularly good reason except that
the increment expression is not used in the for pattern. I guess it offends
my sense of esthetics, which is reason enough to tip the balance, all else
being equal. I might change my mind if someone can demonstrate a big
advantage one way or the other.

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