问题
When using Message Driven BEans, the destination name from where to receive messages is hard coded in the annotation @MessageDriven(mappedName = "someDestinationName")
Is there a way to add this information at runtime? Bellow is a sample Message Driven Bean class.
package mdb.beans;
import javax.ejb.ActivationConfigProperty;
import javax.ejb.MessageDriven;
import javax.jms.Message;
import javax.jms.MessageListener;
@MessageDriven(mappedName = "someDestinationName", activationConfig =
{
@ActivationConfigProperty(propertyName = "acknowledgeMode", propertyValue = "Auto-acknowledge"),
@ActivationConfigProperty(propertyName = "destinationType", propertyValue = "javax.jms.Queue")
})
public class MDBSample implements MessageListener
{
public MDBSample()
{
// constructor
}
@Override
public void onMessage(Message message)
{
// logic when message received
}
}
回答1:
As far as I know, no, you cannot do that.
Because, the coupling of the destination (which is a String) and the bean (which is a class) is done once in the deploy-time, you cannot change the destination programmatically.
Maybe there is a hack for re-binding; I mean forcing the container to release MDB, then change destination and re-initalize (go through dependency injection, then post construct steps etc.) but I doubt the application servers will allow that.
Excerpt from JSR-318 (EJB 3.1 spec);
5.4.17 Association of a Message-Driven Beanwith a Destination or Endpoint
A message-driven bean is associated with a destination or endpoint when the bean is deployed in the container. It is the responsibility of the Deployer to associate the message-driven bean with a destination or endpoint.
5.4.17.1 JMS Message-Driven Beans
A JMS message-driven bean is associated with a JMS Destination (Queue or Topic) when the bean is deployed in the container. It is the responsibility of the Deployer to associate the message-driven bean with a Queue or Topic.
来源:https://stackoverflow.com/questions/16033568/configuring-mappedname-annotation-in-message-driven-bean-dynamically