Defining a non null map variable in Apache Camel routes

Question

I've a situation where I want to define a non null Map variable in Camel route and put value into it. But I couldn't find a way to do that.

I tried defining a map by setting resultType as "java.util.HashMap" in setProperty field.But I got NullPointerException.

   <route id = "update_fields">
    <from uri ="direct:update_fields"/>
    <setProperty propertyName="fieldMap">
    <simple resultType="java.util.HashMap">[:]</simple>              
    </setProperty>               
    <groovy>exchange.getProperty('fieldMap').put(body.rId,body.b_id)</groovy>
    </route>

Answer 1

Use groovy language ala:

<setProperty propertyName="fieldMap">
  <groovy>new HashMap()</groovy>              
</setProperty>