我如何以编程方式注册 AbstractMongoEventListener? [英] How do i register AbstractMongoEventListener programmatically?

问题描述

在我的 Spring Boot 应用程序中，我有一个配置，它从 Mongo 数据库读取条目.

完成后，创建了我的 AbstractMongoEventListener 子类，即使它在不同的表和不同的范围(我自己的自定义 @CustomerScope)上运行.>

这里是听众:

@CustomerScoped@成分公共类 ProjectsRepositoryListener 扩展 AbstractMongoEventListener<Project>{@覆盖public void onAfterSave(项目源，DBObject dbo){System.out.println("保存");}}

这里是配置:

@Configuration公共类 MyConfig {@自动连线私人客户存储库客户；@PostConstruct公共无效初始化客户(){对于(客户客户:customers.findAll()){System.out.println(customer.getName());}}}

我发现完全实例化侦听器令人惊讶.特别是因为它在对客户存储库的调用完成后被很好地实例化.

有没有办法防止这种情况发生?我正在考虑以编程方式为每个表/范围注册它，没有注释魔法.

解决方案

为了防止自动实例化，监听器不能被注解为 @Component.配置需要获取可以自动装配的 ApplicationContext.

因此，我的配置类如下所示:

@Autowired私有 AbstractApplicationContext 上下文；私有无效 registerListeners() {ProjectsRepositoryListener firstListener = beanFactory.createBean(ProjectsRepositoryListener.class);context.addApplicationListener(firstListener);MySecondListener secondListener = beanFactory.createBean(MySecondListener.class);context.addApplicationListener(secondListener);}

请注意，这适用于任何 ApplicationListener，而不仅仅是 AbstractMongoEventListener.

In my Spring Boot application, i have a configuration, which reads entries from a Mongo database.

After this is done, my subclass of AbstractMongoEventListener is created, even though it operates on a different table and different scope (my own custom @CustomerScope).

Here is the listener:

@CustomerScoped
@Component
public class ProjectsRepositoryListener extends AbstractMongoEventListener<Project> {

    @Override
    public void onAfterSave(Project source, DBObject dbo) {
        System.out.println("saved");
    }
}

And here the configuration:

@Configuration
public class MyConfig {

    @Autowired
    private CustomersRepository customers;

    @PostConstruct
    public void initializeCustomers() {
        for (Customer customer : customers.findAll()) {
            System.out.println(customer.getName());
        }
    }
}

I find it surprising that the listener is instantiated at all. Especially since it is instantiated well after the call to the customers repository has finished.

Is there a way to prevent this? I was thinking of programmatically registering it per table/scope, without annotation magic.

解决方案

To prevent auto-instantiation, the listener must not be annotated as @Component. The configuration needs to get ahold of the ApplicationContext, which can be autowired.

Thus, my configuration class looks like this:

@Autowired
private AbstractApplicationContext context;

private void registerListeners() {
    ProjectsRepositoryListener firstListener = beanFactory.createBean(ProjectsRepositoryListener.class);
    context.addApplicationListener(firstListener);

    MySecondListener secondListener = beanFactory.createBean(MySecondListener.class);
    context.addApplicationListener(secondListener);
}

Note that this works for any ApplicationListener, not just AbstractMongoEventListener.

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