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Re: Glitch in Java Collections (No descendingMap in LinkedHashMap)

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Jan Burse <janburse@fastmail.fm> wrote:
> Lew schrieb:
>> Again, my concern is that 'Set' doesn't promise predictable 
>> iteration order, in fact, exactly the opposite. 
>> The only iterators available for a 'Map' are through its 'Set'-
>> returning methods, which result in a collection that promises 
>> not to have a predictable iteration order.

> Well that is not fully correct. When you get a keySet, entrySet or
> valueSet, you indeed get an object that is derived from the class
> Set. And this class in itself has indeed no guarantee.

(snip)

> But LinkedHashMap does not implement this interface as I mentioned
> in my initial post. And HashMap, the super class, has no guarantee.
> So this is probably a Java glitch.

> But I was not aspiring in detecting this glitch. I am more interested
> in the reverse iterator. Any route to get at a reverse iterator?

There are some problems in PracticeIt that require one to reverse
the order of something. Especially in the section on stacks.
Write a loop that takes objects and pushes them onto a stack.
Then remove them from the stack in the appropriate order.

Usually two lines instead of one.

http://webster.cs.washington.edu:8080/practiceit/

-- glen

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Thread

Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-04 14:09 +0200
  Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Robert Klemme <shortcutter@googlemail.com> - 2012-10-04 23:01 +0200
    Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Lew <lewbloch@gmail.com> - 2012-10-04 14:43 -0700
      Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-05 00:17 +0200
      Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Robert Klemme <shortcutter@googlemail.com> - 2012-10-05 19:11 +0200
        Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Lew <lewbloch@gmail.com> - 2012-10-05 11:05 -0700
          Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-05 20:18 +0200
          Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-10-05 12:06 -0700
            Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Lew <lewbloch@gmail.com> - 2012-10-05 13:04 -0700
              Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-05 23:44 +0200
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-05 23:50 +0200
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-06 00:00 +0200
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-10-05 23:39 +0000
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-06 12:18 +0200
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-06 12:22 +0200
              Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Daniel Pitts <newsgroup.nospam@virtualinfinity.net> - 2012-10-05 15:51 -0700
          Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Robert Klemme <shortcutter@googlemail.com> - 2012-10-06 13:53 +0200
  Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-09 14:16 -0600
    Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-10 09:00 -0600
      Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-10-10 11:34 -0400
        Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-10 10:28 -0600
          Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-10 11:45 -0600
            Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Lew <lewbloch@gmail.com> - 2012-10-10 10:52 -0700
              Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-10 12:47 -0600
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-11 14:17 -0600
            Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-10-10 18:20 -0400
              Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-10 16:51 -0600
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-12 14:34 +0200
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jim Janney <jjanney@shell.xmission.com> - 2012-10-12 09:12 -0600
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Eric Sosman <esosman@comcast-dot-net.invalid> - 2012-10-12 11:42 -0400
                Re: Glitch in Java Collections (No descendingMap in LinkedHashMap) Jan Burse <janburse@fastmail.fm> - 2012-10-12 21:02 +0200

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