> ## Documentation Index
> Fetch the complete documentation index at: https://docs.aseeflow.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Expression Resolving

The `camunda-engine-cdi` and `camunda-engine-cdi-jakarta` libraries expose CDI beans via Expression Language,
using a custom resolver. This makes it possible to reference beans from the process:

```xml theme={null}
<userTask id="authorizeBusinessTrip" name="Authorize Business Trip"
                        camunda:assignee="#{authorizingManager.account.username}" />
```

Where "authorizingManager" could be a bean provided by a producer method:

```java theme={null}
@Inject
@ProcessVariable
private Object businessTripRequesterUsername;

@Produces
@Named
public Employee authorizingManager() {
        TypedQuery<Employee> query = entityManager.createQuery("SELECT e FROM Employee e WHERE e.account.username='"
                + businessTripRequesterUsername + "'", Employee.class);
        Employee employee = query.getSingleResult();
        return employee.getManager();
}
```

We can use the same feature to call a business method of an EJB in a service task, using the `camunda:expression="${myEjb.method()}"`-extension.
Note that this requires a `@Named`-annotation on the MyEjb-class.