17.1.2. Accessing local SLSBs
Assume that we have a web controller that needs to use a local EJB.
We’ll follow best practice and use the EJB Business Methods Interface pattern, so that the EJB’s local interface extends a non EJB-specific business methods interface. Let’s call this business methods interface MyComponent.
public interface MyComponent {
...
}
(One of the main reasons to the Business Methods Interface pattern is to ensure that synchronization between method signatures in local interface and bean implementation class is automatic. Another reason is that it later makes it much easier for us to switch to a POJO (plain java object) implementation of the service if it makes sense to do so) Of course we’ll also need to implement the local home interface and provide a bean implementation class that implements SessionBean and the MyComponent business methods interface. Now the only Java coding we’ll need to do to hook up our web tier controller to the EJB implementation is to expose a setter method of type MyComponent on the controller. This will save the reference as an instance variable in the controller:
private MyComponent myComponent;
public void setMyComponent(MyComponent myComponent) {
this.myComponent = myComponent;
}
We can subsequently use this instance variable in any business method in the controller. Now assuming we are obtaining our controller object out of a Spring ApplicationContext or BeanFactory, we can in the same context configure a LocalStatelessSessionProxyFactoryBean instance, which will be EJB proxy object. The configuration of the proxy, and setting of the myComponent property of the controller is done with a configuration entry such as:
<bean id="myComponent"
class="org.springframework.ejb.access.LocalStatele ssSessionProxyFactoryBean">
<property name="jndiName" value="myComponent"/>
<property name="businessInterface" value="com.mycom.MyComponent"/>
</bean>
<bean id="myController" class="com.mycom.myController">
<property name="myComponent" ref="myComponent"/>
</bean>
Accessing local SLSBs: does local interface still extend EJBLocalObject?
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Originally Posted by jim
