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    <p>Skipping over your Iterator/Iterable confusion (and Iterable is basically an Iterator factory... so you need to write an Iterator either way), I think you mean something like this:</p> <pre><code>Iterator&lt;Test&gt; getTests(final Map&lt;String,Test&gt; testMap, final Set&lt;String&gt; strings) { return new Iterator&lt;Test&gt;() { private final Iterator&lt;String&gt; keyIter = strings.iterator(); private String lastKey; public boolean hasNext() { return keyIter.hasNext(); } public Test next() { lastKey = keyIter.next(); return testMap.get(lastKey); } public void remove() { testMap.remove(lastKey); } }; } </code></pre> <p>And if you want to return an Iterable, well, that just has to be a factory for those:</p> <pre><code>Iterable&lt;Test&gt; getTests(final Map&lt;String,Test&gt; testMap, final Set&lt;String&gt; strings) { return new Iterable&lt;Test&gt;() { public Iterator&lt;Test&gt; iterator() { return new Iterator&lt;Test&gt;() { private final Iterator&lt;String&gt; keyIter = strings.iterator(); private String lastKey; public boolean hasNext() { return keyIter.hasNext(); } public Test next() { lastKey = keyIter.next(); return testMap.get(lastKey); } public void remove() { testMap.remove(lastKey); } }; } }; } </code></pre> <p>For extra credit, you can parameterise this method itself and have a generic way of iterating over a selection from a map:</p> <pre><code>Map&lt;String, Action&gt; map; Set&lt;String&gt; keys; for (Action x : filterMap(map, keys)) { } </code></pre>
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    1. POJava iterator
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    1. COThe lazy iterator way... I thought of that, but was too lazy to actually write it. :P
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      1. USMichael Myers
    2. COremove() should probably remove the Test from the Map (either that or throw UnsupportedOperationException). It should not modify the passed-in Set. In fact, you should almost certainly make a copy of the passed-in Set.
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      1. USNamshubWriter
    3. COYes, I was trying to get too clever and probably shouldn't have tried to support remove(). I think it's fair to leave copying the passed-in set as the caller's responsibility. Without knowing how this is actually going to be used, it's hard to say, but if the results are just used to quickly loop over the map once then duplicating the keys is excessive.
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