如何从 MessagingGateway 设置 Jpa 查询参数？

Question

I'm implementing Transactional Outbox pattern using Java. The Message Relay Service will poll the Outbox table for entries, and after an outbox message is found and processed it will update the Outbox entry.

Question is, how do I set the parameter from MessagingGateway to the Jpa Query?

@Bean
public JpaExecutor jpaUpdateStateExecutor() {
    JpaExecutor jpaExecutor = new JpaExecutor(this.entityManagerFactory);
    jpaExecutor.setNamedQuery("myQuery");
    jpaExecutor.setUsePayloadAsParameterSource(true);
    jpaExecutor.setExpectSingleResult(true);
    return jpaExecutor;
}

@Bean
@ServiceActivator(inputChannel = "jpaChannel")
public MessageHandler jpaOutbound() {
    JpaOutboundGateway gateway = new JpaOutboundGateway(jpaUpdateStateExecutor());
    gateway.setGatewayType(OutboundGatewayType.UPDATING);
    return gateway;
}

My Gateway:

@MessagingGateway
public interface MyGateway {
    @Gateway(requestChannel = "jpaChannel")
    @Transactional
    void jpaActions(Long idOfEntity);
}

My domain object:

@Entity
@Getter
@Setter
@ToString
@NoArgsConstructor
@Table
@NamedQuery(name = "myQuery", query = "UPDATE MyTable SET state = 'PROCESSED' WHERE id = :id")
public class Outbox {
    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private Long id;

    private String state;
}

Answer 1

It would be great to see your query and how you'd like to have that Long idOfEntity to be mapped to some query param.

The doc for that setUsePayloadAsParameterSource looks like this:

use-payload-as-parameter-source

If set to true, the payload of the Message is used as a source for parameters. If set to false, the entire Message is available as a source for parameters. If no JPA Parameters are passed in, this property defaults to true. This means that, if you use a default BeanPropertyParameterSourceFactory , the bean properties of the payload are used as a source for parameter values for the JPA query. However, if JPA Parameters are passed in, this property, by default, evaluates to false. The reason is that JPA Parameters let you provide SpEL Expressions. Therefore, it is highly beneficial to have access to the entire Message, including the headers. Optional.

https://docs.spring.io/spring-integration/docs/current/reference/html/jpa.html#jpa-outbound-gateway-common-parameters

Perhaps you'd prefer to have that option as false and then in your query you could use a param for that idOfEntity as just a :payload placeholder.