How do I fire an action every time a JBPM Node enters?

One of the key components of jBPM is the Service Task, which provides a way to integrate custom actions and logic into your business processes. In this article, we will explore how to utilize a jBPM Service Task to execute Java actions when entering or leaving a specific node.

Understanding the jBPM Service Task

The Service Task in jBPM allows you to define a custom action or logic to be executed as part of a business process. It acts as a bridge between your business process and the external services or custom Java code you want to invoke. By utilizing the Service Task, you can extend the capabilities of your business processes and perform complex operations.

Each ServiceTask includes On-entry and on-exit actions which are executed upon entry or exit of this node, respectively.

A common use for an On-entry action is to set variables when we enter the node

kcontext.setVariable("myvar","foo");

A Service Task is a task that does not require any human action with the engine. It can be executed by the engine synchronously or asynchronously. You can use Service Tasks to invoke external services via REST, send e-mails, log messages, and even invoke complex business rules in order to define the next steps to be taken in the process flow.

As an example, see the following tutorial to learn more about REST Service Task: How to use a REST WorkItem Handler in jBPM