title: Kafka Number of messages in a topic
body: <p>I need the number of messages in a kafka topic stored.
  This is not concerned with whether any consumer has consumed the messages or not.</p>
  
  <pre><code>kafka-run-class.sh kafka.tools.GetOffsetShell --broker-list localhost:9092,localhost:9093,localhost:9094 --topic test-topic
  </code></pre>
  
  <p>The above gives the offset number for the topic?</p>
  
  <p>Is the above equal to the number of messages currently stored in the kafka topic?</p>