Example service task with a template as input parameter mapping

templateServiceTask.xml

<bpmn2:serviceTask id="emailTask" name="Send email" camunda:class="org.camunda.bpm.examples.EmailService">
  <bpmn2:extensionElements>
    <camunda:inputOutput>
      <camunda:inputParameter name="emailBody">
        <camunda:script scriptFormat="freemarker">
          <![CDATA[
            Dear ${customer},
            Welcome to camunda BPM ${version}. Please visit one of these links
            for more information about camunda BPM:

            <#list links as link>
              <a href="${link.href}">${link.text}</a>
            </#list>

            Cheers,
            ${supportUser}
          ]]>
        </camunda:script>
      </camunda:inputParameter>
    </camunda:inputOutput>
  </bpmn2:extensionElements>
</bpmn2:serviceTask>