LinkedHashSet or ArrayList
<p>I wish to</p>

<ol>
<li>Avoid duplicated item being inserted.</li>
<li>When I iterate through the collection class, the returned item is same as insertion order.</li>
</ol>

<p>May I know, what thing I should consider, to choose either ArrayList (explicitly perform contains check before insertion) or LinkedHashSet?</p>

<p>Thanks.</p>
