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From: Joshua Cranmer <Pidgeot18@verizon.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: java.lang vs java.util
Date: Sat, 02 Apr 2011 16:22:21 -0400
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On 04/02/2011 12:11 AM, Lawrence D'Oliveiro wrote:
> Surprising to see something defined in java.lang
> <http://developer.android.com/reference/java/lang/Iterable.html>  depend on
> something defined in java.util
> <http://developer.android.com/reference/java/util/Iterator.html>.
>
> Surely the hierarchy should go the other way?

Iterator is needed for for-each loops, which were added several versions 
after java.util.Iterator was introduced. Iterablity, being a "language 
feature" was put in java.lang, but to be backwards-compatible with those 
who already implemented java.util.Iterator, they used that class. There 
actually is a note somewhere saying that the developers would prefer to 
not have to do this, but decided that backwards compatibility was more 
important than modularity aesthetics.

-- 
Beware of bugs in the above code; I have only proved it correct, not 
tried it. -- Donald E. Knuth