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From: Mike Amling <mamling@chaff.us>
Newsgroups: comp.lang.java.programmer
Subject: Two surprises in for (:)
Date: Fri, 1 Jul 2016 12:55:20 -0500
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I was surprised that the javac compiler accepted the following:

String[] foo={"a", "b"};
for (final String who : foo) {
}

because it seems strange to have a for loop's variable work when final. 
After all,

for (final int i=0; i<7; ++i) {
}

gets an error.

But for (final String who : foo) is more like an abbreviation of

for (final Iterator<String> iter=foo.iterator(); iter.hasNext(); ) {
   final String who=iter.next();
}

wherein it's not strange that who can be final.

My second surprise was that the compiler rejects

String[] foo={"a", "b"};
for (final Iterator<String> iter=foo.iterator(); iter.hasNext(); ) {
   final String who=iter.next();
}

apparently because arrays, unlike everything else accepted after the : 
in a for(:), do not actually implement the Iterable interface.

--Mike Amling
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