1、指定限定名注入實現(xiàn)類

1.1、定義一個接口

public interface AnimalService {
    public void sound();
}

1.2、創(chuàng)建多個實現(xiàn)類

@Service("s1")
public class CatService implements AnimalService {
    @Override
    public void sound() {
        System.out.println("喵喵喵");
    }
}

@Service()
public class DogService implements AnimalService {
    @Override
    public void sound() {
        System.out.println("汪汪汪");
    }
}

@Service("s3")
public class CattleService implements AnimalService {
    @Override
    public void sound() {
        System.out.println("汪汪汪");
    }
}

1.3、指定限定名注入實現(xiàn)類

@RunWith(SpringRunner.class)
@SpringBootTest
public class Main {
    @Autowired
    @Qualifier(value = "s1")
    AnimalService animalService1;    //正常啟動
    //沒有指定bean注入名字的，使用該類首字符小寫的bean的名字
    //使用默認(rèn)的
    @Resource(name = "dogService")
    AnimalService animalService2;    //正常啟動
    //通過@Resource注入，根據(jù)@Service指定的名稱區(qū)分
    @Resource(name = "s3")
    AnimalService animalService3;    //正常啟動
    @Test
   public void test1() {
        animalService1.sound();
        animalService2.sound();
        animalService3.sound();     
    }
}

 2、Map名注入實現(xiàn)類

2.1、定義一個接口

public interface AnimalService {
    public void sound();
}

2.2、創(chuàng)建多個實現(xiàn)類

@Service("s1")
public class CatService implements AnimalService {
    @Override
    public void sound() {
        System.out.println("喵喵喵");
    }
}

@Service()
public class DogService implements AnimalService {
    @Override
    public void sound() {
        System.out.println("汪汪汪");
    }
}

2.3、枚舉

public enum AnimalTypeEnum {
    DOG(1, "狗狗", "dogService"),
    CAT(2, "貓咪", "catService");
    public Integer code;
    public String msg;
    public String service;
    public static AnimalTypeEnum getAnimalTypeEnum (Integer code) {
        return (AnimalTypeEnum )Arrays.stream(values()).filter((item) -> {
            return item.code.equals(code);
        }).findFirst().orElseThrow(() -> {
            return new BusinessException("biz animal type is not exist");
        });
    }
    private AnimalTypeEnum (final Integer code, final String msg, final String service) {
        this.code = code;
        this.msg = msg;
        this.service = service;
    }
}

2.4、指定限定名注入實現(xiàn)類

@RunWith(SpringRunner.class)
@SpringBootTest
public class Main {
    @Autowired
    Map<String, AnimalService> animalServiceMap;
    @Test
   public void test1() {  
        String service = AnimalTypeEnum.getAnimalTypeEnum(1).service;
        AnimalService animalService = animalServiceMap.get(service);
        animalService.sound();
    }
}