title: String conversion from Utf8
body: <pre><code>   record.get("key")
  </code></pre>
  
  <p>Here, <code>record</code> is <code>org.apache.avro.GenericReord</code>. In my case it returns <code>utf8</code>. I need String. So possibilities I found</p>
  
  <pre><code>   record.get("key").toString() - I prefer cast than this method
     record.get("key")+""         - It calls string concatenation method 
  </code></pre>
  
  <p>The above two works. </p>
  
  <pre><code>   (String)record.get("key") - Obviously it throws a classcastexception.
     new String(record.get("key")) - new String(Object) is undefined.
  </code></pre>
  
  <p>The above two doesn't work.</p>
  
  <p>My doubt is which one is better in terms of performance <code>toString()</code> and <code>+</code> in my scenario.</p>