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copied!<p>It doesn't make sense for <code>Enumeration</code> to implement <code>Iterable</code>. <code>Iterable</code> is a factory method for <code>Iterator</code>. <code>Enumeration</code> is analogous to <code>Iterator</code>, and only maintains state for a single enumeration.</p> <p>So, be careful trying to wrap an <code>Enumeration</code> as an <code>Iterable</code>. If someone passes me an <code>Iterable</code>, I will assume that I can call <code>iterator()</code> on it repeatedly, creating as many <code>Iterator</code> instances as I want, and iterating independently on each. A wrapped <code>Enumeration</code> will not fulfill this contract; don't let your wrapped <code>Enumeration</code> escape from your own code. (As an aside, I noticed that Java 7's <a href="http://docs.oracle.com/javase/7/docs/api/java/nio/file/DirectoryStream.html" rel="noreferrer"><code>DirectoryStream</code></a> violates expectations in just this way, and shouldn't be allowed to "escape" either.)</p> <p><code>Enumeration</code> is like an <code>Iterator</code>, not an <code>Iterable</code>. A <code>Collection</code> is <code>Iterable</code>. An <code>Iterator</code> is not.</p> <p>You can't do this:</p> <pre><code>Vector<X> list = … Iterator<X> i = list.iterator(); for (X x : i) { x.doStuff(); } </code></pre> <p>So it wouldn't make sense to do this:</p> <pre><code>Vector<X> list = … Enumeration<X> i = list.enumeration(); for (X x : i) { x.doStuff(); } </code></pre> <p>There is no <code>Enumerable</code> equivalent to <code>Iterable</code>. It could be added without breaking anything to work in for loops, but what would be the point? If you are able to implement this new <code>Enumerable</code> interface, why not just implement <code>Iterable</code> instead?</p>

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