Chapter 27. Activities, Tasks and Sub-Processes

1. Open the process in Process Editor.
2. Open the Properties panel on the right and click the Value field next to the Imports property. Click the arrow that appears on the right to open the Editor for Imports window.

3. Click Add Import to import the required WSDL (Web Services Description Language) values. For example:

   • Import Type: wsdl

   • WSDL Location: http://localhost:8080/sample-ws-1/SimpleService?wsdl

     The WSDL location points to the WSDL file of your service.

   • WSDL Namespace: http://bpmn2.workitem.process.jbpm.org/

     The WSDL namespace must match targetNamespace from your WSDL file.

4. Drag a Service Task (Tasks → Service) from the Object Library into the canvas.

5. Click the task, and in the Properties panel on the right, set the following:

   • Service Implementation: Webservice
   • Service Interface: SimpleService
   • Service Operation: hello

6. In the Core Properties section, click the Value field next to the Assignments property. Click the arrow that appears on the right to open the Data I/O window and do the following:

   1. Provide a data input named Parameter.
   2. Optionally, provide a data output named Result.

   For an example setting in the Service Task Data I/O window, see the image below:

   

1. Create an XML binding file with the following contents.

   <?xml version="1.0" encoding="UTF-8"?>
   <bindings xmlns="http://java.sun.com/xml/ns/jaxb" xmlns:xsi="http://www.w3.org/2000/10/XMLSchema-instance" xmlns:xjc="http://java.sun.com/xml/ns/jaxb/xjc" xsi:schemaLocation="http://java.sun.com/xml/ns/jaxb http://java.sun.com/xml/ns/jaxb/bindingschema_2_0.xsd" version="2.1">
     <globalBindings>
       <serializable uid="1" />
     </globalBindings>
   </bindings>

2. Add the Apache CXF Maven plug-in (cxf-codegen-plugin) to the pom.xml file of the project:

   <build>
     <plugins>
       <plugin>
         <groupId>org.apache.cxf</groupId>
         <artifactId>cxf-codegen-plugin</artifactId>
         <version>CXF_VERSION</version>
         ...
       </plugin>
     </plugins>
   <build>

Invoking Java Method in Red Hat JBoss Developer Studio

1. In Red Hat JBoss Developer Studio, open the business process that you want to add a Service Task to, or create a new process with a start and an end event.
2. Select Window → Show View → Properties, and click Interfaces in the lower-right corner of the Properties panel.

3. Click the Import icon ( ) to open the Browse for a Java type to Import window. To find the Java type, start typing WeatherService in the Type field. In the Available Methods list box below, select the int getTemperature(String) method. Click OK.

   Note that it is also possible to select the Create Process Variables check box to automatically import process variables with generated names. In this procedure, the process variables are created manually.

4. In the Properties panel, click Data Items. Click the Add icon ( ) to create a local process variable:

   1. Enter the process variable details:

      • Name: location
      • Data Type: java.lang.String

   2. Create a second process variable:

      • Name: temperature
      • Data Type: java.lang.Integer

5. Add a Service Task to the process:

   1. Drag a Service Task (Tasks → Service Task) from the Palette panel on the right to the canvas.

   2. Double-click the Service Task on the canvas to open the Edit Service Task window. Click Service Task and set the following properties:

      • Implementation: Java
      • Operation: WeatherService/getTemperature
      • Source: location
      • Target: temperature
   3. Click OK and save the process.

6. The Java application that starts the business process must be available. If you created a new business process and do not have the application, create a new jBPM project with an example application:

   1. Click File → New → Other → jBPM → jBPM project. Click Next.
   2. Select the second option and click Next to create a project and populate it with some example files to help you get started quickly.
   3. Enter a project name and select the Maven radio button. Click Finish.

7. Register work item handlers. In the src/main/resources/META-INF/ directory, create a file named kie-deployment-descriptor.xml with the following contents:

   <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
   <deployment-descriptor xsi:schemaLocation="http://www.jboss.org/jbpm deployment-descriptor.xsd" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
     <persistence-unit>org.jbpm.domain</persistence-unit>
     <audit-persistence-unit>org.jbpm.domain</audit-persistence-unit>
     <audit-mode>JPA</audit-mode>
     <persistence-mode>JPA</persistence-mode>
     <runtime-strategy>SINGLETON</runtime-strategy>
     <marshalling-strategies/>
     <event-listeners/>
     <task-event-listeners/>
     <globals/>
     <work-item-handlers>
       <work-item-handler>
         <resolver>mvel</resolver>
         <identifier>new org.jbpm.process.instance.impl.demo.SystemOutWorkItemHandler()</identifier>
         <parameters/>
         <name>Log</name>
       </work-item-handler>
       <work-item-handler>
         <resolver>mvel</resolver>
         <identifier>new org.jbpm.process.workitem.bpmn2.ServiceTaskHandler(ksession, classLoader)</identifier>
         <parameters/>
         <name>Service Task</name>
       </work-item-handler>
       <work-item-handler>
         <resolver>mvel</resolver>
         <identifier>new org.jbpm.process.workitem.webservice.WebServiceWorkItemHandler(ksession, classLoader)</identifier>
         <parameters/>
         <name>WebService</name>
       </work-item-handler>
       <work-item-handler>
         <resolver>mvel</resolver>
         <identifier>new org.jbpm.process.workitem.rest.RESTWorkItemHandler(classLoader)</identifier>
         <parameters/>
         <name>Rest</name>
       </work-item-handler>
     </work-item-handlers>
     <environment-entries/>
     <configurations/>
     <required-roles/>
     <remoteable-classes/>
     <limit-serialization-classes>true</limit-serialization-classes>
   </deployment-descriptor>

8. Open the ProcessMain.java file that is located in the src/main/java directory, and modify the code of the application that starts the business process:

   1. Initialize the process variables:

      Map<String, Object> arguments = new HashMap<>();
      arguments.put("location", "Brno");
      arguments.put("temperature", -1);

   2. Start the process:

      ksession.startProcess("demo-package.demo-service-task", arguments);

Invoking Java Method in Business Central

1. The invoked Java class must be available either on the class path or in the dependencies of the project. To add the class to the dependencies of the project:

   1. In Business Central, click Authoring → Artifact Repository.
   2. Click Upload to open the Artifact upload window.
   3. Choose the .jar file, and click .
   4. Click Authoring → Project Authoring, and find or create the project you want to use.
   5. Click Open Project Editor and then Project Settings: Project General Settings → Dependencies.
   6. Click Add from repository, locate the uploaded .jar file, and click Select.
   7. Save the project.
2. Open or create the business process to which you want to add a Service Task.

3. In Process Editor, open the Properties panel on the right and click the Value field next to the Imports property. Click the arrow that appears to open the Editor for Imports window. In the window:

   1. Click Add Import and specify the following values:

      • Import Type: default
      • Custom Class Name: fully qualified name of the invoked Java class, for example org.jboss.weather.WeatherService
   2. Click Ok.

4. Create process variables:

   1. In the Properties panel, click the Value field next to the Variable Definitions property. Click the arrow that appears to open the Editor for Variable Definitions window.

   2. Click Add Variable to add the following two process variables:

      • Name: temperature, Defined Types: Integer (or Custom Type: java.lang.Integer)
      • Name: location, Defined Types: String (or Custom Type: java.lang.String)
   3. Click Ok.
5. To add a Service Task into the process, drag and drop a Service Task (Tasks → Service) from the Object Library panel on the left into the canvas.

6. Click the Service Task on the canvas to open its properties on the right, and set the following properties:

   • Service Interface: org.jboss.weather.WeatherService
   • Service Operation: getTemperature

7. Click the Value field next to the Assignments property. Click the arrow that appears to open the Data I/O window and do the following:

   1. Click Add next to Data Inputs and Assignments and add the following:

      • Name: Parameter, Data Type: String, Source: location
      • Name: ParameterType, Data Type: String, Source: java.lang.String (to add this value, click Constant …​ and type it manually)

   2. Click Add next to Data Outputs and Assignments and add the following:

      • Name: Result, Data Type: Integer, Target: temperature
   3. Click Save.