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From: v_borchert@despammed.com (Volker Borchert)
Newsgroups: comp.lang.java.programmer
Subject: Re: looping through a list, starting at 1
Date: 2 Aug 2011 19:32:44 GMT
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Robert Klemme wrote:
> If there are performance issues then we can optimize later anyway.

In that case, I'd go for something like

if (l instanceof RandomAccess) {
  for (int i = 1, n = l.size(); i < n; ++i) {
    final E e = l.get(i);
    // ...
  }
} else {
  final Iterator i = l.iterator();
  if (i.hasNext()) {
    i.next();
    while (i.hasNext()) {
      final E e = i.next();
      // ...
    }
  }
}

and hope that all custom List implementations encountered truthfully
implement or not RandomAccess, and that those that do have a fast size()
and those that don't have a fast Iterator.hasNext().

-- 

"I'm a doctor, not a mechanic." Dr Leonard McCoy <mccoy@ncc1701.starfleet.fed>
"I'm a mechanic, not a doctor." Volker Borchert  <v_borchert@despammed.com>