title: jUnit fail() conventions
body: <p>I am wondering, by convention, when a test fails, is it appropriate to:</p>
  
  <ul>
  <li>Say why it failed (business logic)</li>
  <li>Say why the message is seen (exception should have been thrown and it's not)</li>
  </ul>
  
  <p>For instance,</p>
  
  <pre><code>fail("Accessed the element which does not exist");
  </code></pre>
  
  <p>or </p>
  
  <pre><code>fail("ArrayIndexOutOfBoundException was expected but something bad happened");
  </code></pre>
  
  <p>Which one is generally preferred/ accepted?</p>