title: Mapper output.collect()?
body: <p>The mapper invokes this two times.</p>
  
  <pre><code>out.collect(new Text("Car"),new Text("Subaru");
  out.collect(new Text("Cr-v"),new Text("Honda");
  </code></pre>
  
  <p>Does the <code>reduce()</code> also get called two times ?</p>