java - 使用 @Resource 基于 CDI 构造函数的注入(inject)

Question

是否可以对 @Resource 类型的实例进行基于构造函数的 CDI 注入(inject)？

我有以下类(class):

class MyClass {

  @Resource
  private ManagedExecutorService executorService;

  @Inject
  private MyService myservice;

}

我想把它转换成这样的东西:

class MyClass {

  private final ManagedExecutorService executorService;
  private final MyService myservice;

  @Inject
  MyClass(ManagedExecutorService executorService, MyService myService) 
  {
    this.executorService = executorService;
    this.myService = myService;
  }

}

这将使类不可变并且更容易进行单元测试。问题在于，由于 executorService 需要通过 @Resource 注解获取，因此它似乎无法通过构造函数注入(inject)。

Answer 1

这就是我最终所做的 - 我创建了一个生产者类来管理资源对象:

public class ExecutorServiceProducer {

    @Resource
    private ManagedExecutorService managedExecutorService;

    @Produces
    @Managed
    public ExecutorService createManagedExecutorService() {
        return managedExecutorService;
    }

}

我创建了这个自定义注释:

@Qualifier
@Retention(RUNTIME)
@Target({TYPE, METHOD, FIELD, PARAMETER})
public @interface Managed {
}

然后我可以按如下方式注释我的类:

class MyClass {

  private final ExecutorService executorService;
  private final MyService myservice;

  @Inject
  MyClass(@Managed ExecutorService executorService, MyService myService) 
  {
    this.executorService = executorService;
    this.myService = myService;
  }

}

这样我就可以通过提供我自己的 ExecutorService(非容器管理)实例来对类进行单元测试。