I. Activiti Message Event Overview

A Message Event is a named message that always directs towards a single receiver.

To define Message Event, we use messageEventDefinition element. For example:

<message id="messageId" name="messageName" />

<process id="simpleProcess" name="Simple Process">

	<startEvent id="start_one">
		<messageEventDefinition messageRef="messageId" />
	</startEvent>
	...
</process>

Activiti Engine is not concerned with receiving messages. We have to implement our own infrastructure to deal with received messages. Then we can decide what to do with them.

In the example, we use message to trigger the start of a Process Instance. These are some methods (from Runtime Service):

ProcessInstance startProcessInstanceByMessage(String messageName);
ProcessInstance startProcessInstanceByMessage(String messageName, Map processVariables);
ProcessInstance startProcessInstanceByMessage(String messageName, String businessKey, Map processVariables);

II. Practice

1. Technology

- Java 1.8 - Maven 3.3.9 - Spring Tool Suite – Version 3.8.4.RELEASE - Spring Boot: 1.5.3.RELEASE

More at:

https://grokonez.com/java-integration/activiti-message-event-spring-boot-example

How to create Activiti Message Event with Spring Boot Example