Question

我有一个接口，并且为此有一些实现。每个实现都属于某种类型。我希望当我使用自动装配时，我能够获得特定类型的所有实现。我该怎么办？

public interface someInterface{}

public class impl1OfType1 implements someInterface{}
public class impl2OfType1 implements someInterface{}

public class impl1OfType2 implements someInterface{}
public class impl2OfType2 implements someInterface{}

public class someClass{
   @autowired
   public someClass(List<someInterface> interfaceList){}

}

我只想获取impl1OfType1和impl2OfType1。并非全部执行。而在其他地方，我只想获取impl1OfType2和impl2OfType2。

更具体的示例-

    public interface EntityCreator{
      createEntity();
    }

    @Component
    public class DogCreator implements entityCreator{}
    @Component
    public class CatCreator implements entityCreator{}
    @Component
    public class CarCreator implements entityCreator{}
    @Component
    public class TruckCreator implements entityCreator{}

    @Component
    public class AnimalsFactory{
       @Autowired
       public AnimalsFactory(List<EntityCreator> creators){}

    }

Answer 1

解决方案将使用@Qualifier。

@Component
@Qualifier("place1")
class Impl1OfType2 implements SomeInterface {}

@Component
@Qualifier("place1")
class Impl2OfType2 implements SomeInterface {}

@Service
class SomeClass {
    @Autowired
    public SomeClass(@Qualifier("place1") List<SomeInterface> interfaceList) {
        System.out.println(interfaceList);
    }
}

我略微更改了名称以遵守Java约定。它们仍然有点笨拙且无上下文。

更新

您可能会使用泛型，Spring善于处理它们。例如，它将仅将DogCreator和CatCreator注入到List<EntityCreator<Animal>>中。

interface Animal {}
interface Machine {}

interface EntityCreator<T> {}

@Component
class DogCreator implements EntityCreator<Animal> {}
@Component
class CatCreator implements EntityCreator<Animal> {}

@Component
class CarCreator implements EntityCreator<Machine> {}
@Component
class TruckCreator implements EntityCreator<Machine> {}

@Component
class AnimalsFactory {
    @Autowired
    public AnimalsFactory(List<EntityCreator<Animal>> creators) { }
}

更新2

您可以编写标记接口，将现有的实现分解为逻辑组。

interface AnimalCreator {}

interface EntityCreator<T> {}

@Component
class DogCreator implements EntityCreator, AnimalCreator {}
@Component
class CatCreator implements EntityCreator, AnimalCreator {}

@Component
class AnimalsFactory {
    @Autowired
    public AnimalsFactory(List<AnimalCreator> creators) {
        System.out.println(creators);
    }

}

Answer 2

如果您通过上述注释更正了您的代码，并且我理解您的问题，那么我认为这可以解决您的问题。

public interface Someinterface<T extends someType> {}
public class someType{}
public class Type1 extends someType{}
public class Type2 extends someType{}

public class TypedInterface1 implements Someinterface<Type1> {}
public class TypedInterface2 implements Someinterface<Type2> {}

public class someClass{
   @Autowired
   public someClass(List<TypedInterface1> interfaceList){}
}

让我知道我是否回答了您的问题。

多种接口相同

2 个答案:

更新

更新2