title: What is difference between LinkedHashSet and FilterSet(Guava)
body: <p>When I trace legacy code, I found something very strange. I can get all the data values from LinkedHashSet, not from the other(FilterSet). </p>
  
  <p>Although data can be seen in unfiltered, but in iteration, I cannot get the required data. Is it because of the predicate? How to get all the data from unfiltered ones?</p>
  
  <p>I found that <strong>guava</strong> is used in the implementation of utilities class in my project. </p>
  
  <p>What is the difference of these two sets? Any help is greatly appreciated.</p>
  
  <p><img src="https://i.stack.imgur.com/FSKj2.png" alt="enter image description here"></p>
  
  <pre><code>Set&lt;A&lt;? extends B, ?&gt;&gt; attributes;
  </code></pre>