title: Optional values with Esper
body: <p>Is there any support in Esper for properties with Optional values?</p>
  
  <p>I'm building a POC with Esper, using Scala, and I have the EPL query working with non-optional values. I have a simple object that I'm using to test with:</p>
  
  <pre><code>case class EsperEvent(@BeanProperty id: Int, @BeanProperty eventtype: Int)
  </code></pre>
  
  <p>And can get my expected results with the following query:</p>
  
  <pre><code>select * from EsperEvent
   match_recognize (
     measures A as event1, B as event2
     pattern (A B)
     define
       A as A.eventtype = 2,
       B as B.eventtype = 3
   )
  </code></pre>
  
  <p>However, when I change my model to the following, I can't seem to get any output from Esper:</p>
  
  <pre><code>case class EsperEvent(@BeanProperty id: Int, @BeanProperty eventtype: Option[Int])
  </code></pre>
  
  <p>I've tried with the above query and also using dynamic properties as follows:</p>
  
  <pre><code>select * from EsperEvent
    match_recognize (
     measures A as event1, B as event2
     pattern (A B)
     define
       A as A.eventtype? = 2,
       B as B.eventtype? = 3
    )
  </code></pre>