13.3. Spring
A Spring XML configuration file can be used to easily define and configure knowledge bases and sessions in a Spring environment, making it possible to access a session and invoke processes from within a Spring application.
The Example SPring Configuration File below sets up a new session based on a knowledge base with one process definition loaded from the classpath.
Example 13.2. Example Spring Configuration File
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:jbpm="http://drools.org/schema/drools-spring"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
http://drools.org/schema/drools-spring org/drools/container/spring/drools-spring-1.2.0.xsd>
<jbpm:kbase id="kbase">
<jbpm:resources>
<jbpm:resource type="BPMN2" source="classpath:HelloWorld.bpmn2"/>
</jbpm:resources>
</jbpm:kbase>
<jbpm:ksession id="ksession" type="stateful" kbase="kbase" />
</beans>
The following code loads the above Spring configuration, retrieves the session, and starts the process:
ClassPathXmlApplicationContext context =
new ClassPathXmlApplicationContext("spring-conf.xml");
StatefulKnowledgeSession ksession = (StatefulKnowledgeSession) context.getBean("ksession");
ksession.startProcess("com.sample.HelloWorld");
Note that you can also inject the session in one of your domain objects; for example, add the following fragment in the configuration file:
<bean id="myObject" class="org.jbpm.sample.MyObject"> <property name="session" ref="ksession" /> </bean>
As a result, the session will be injected into the domain object and can then be accessed directly. For example:
public class MyObject {
private StatefulKnowledgeSession ksession;
public void setSession(StatefulKnowledgeSession ksession) {
this.ksession = ksession;
}
public void doSomething() {
ksession.startProcess("com.sample.HelloWorld");
}
}
