title: Java 8 idiomatic way to apply a Lambda to a List returning another List?
body: <p>What's the most idiomatic mechanism to apply a lambda to every item in a list, returning a list made up of the results?</p>
  
  <p>For example:</p>
  
  <pre><code>List&lt;Integer&gt; listA = ... imagine some initialization code here ...
  
  List&lt;Integer&gt; listB = listA.apply(a -&gt; a * a);   // pseudo-code (there is no "apply")
  
  /* listB now contains the square of every value in listA */
  </code></pre>
  
  <p>I checked the API javadocs and also looked into Apache Commons, but didn't find anything.</p>