首页 > 解决方案 > 如何在供应商内部注入服务。存储库为空

问题描述

我使用供应商创建了一个工厂模式。没关系,它工作得很好。正确服务的路径是可以的,但在将计算的服务内部,存储库为空。似乎没有自动接线。

我尝试使用 @Service 和 @Component 自动装配和注释类,但仍然无法正常工作。

@Service
public class Service {

    public responseDTO calculate(Contract contract, Request request) {

        Supplier<TypeFactory> type = TypeFactory::new;

        //HOW TO AUTOWIRE THIS?
        return type.get().getCalculationMethod(contract.getId()).calculate(request);

    }

}


@Service
public class TypeFactory {

    final static Map<Integer, Supplier<Calculator>> calculationTypeMap = new HashMap<>();

    static {
        calculationTypeMap.put(1, ContractOneType::new);
        calculationTypeMap.put(2, ContractTwoType::new);
    }

    public Calculator getCalculationMethod(Integer type) {
        Supplier<Calculator> method = calculationTypeMap.get(type);
        if (method != null) {
            return method.get();
        }
        throw new IllegalStateException("Type not found");
    }

}
@Service
public interface Calculator {

    ResponseDTO calculate(Request Request);

}
@Service
public class ContractOneType implements Calculator {

    @Autowired
    private ContractRepository contractRepository;

    public ResponseDTO calculate(Request request) {

        ResponseDTO responseDTO = new ResponseDTO();

        Contract contract = contractRepository.findById(request.getId()).orElseThrow(() -> new NotFoundException("id not found"));

        //some calculations here with the contract

        return responseDTO;

    }

}

contractRepository 为空,未自动装配。肯定是。

我的代码中的错误消息:

2019-07-08 10:19:33.078 错误 [-,21fa294c89e1e207,21fa294c89e1e207,false] 19477 --- [nio-8080-exec-1] cldtshGeneralExceptionHandler: msg="Exception", stacktrace="java.lang.NullPointerException

标签: springspring-boot

解决方案


我找到了一个更改我的供应商的解决方案,它正在创建新实例,我只是为我的实现创建实例并为它们设置@Autowired。

这就是为什么我的存储库没有被@Autowired。

这是我的代码:

@Service
public class TypeFactory {

    final static Map<Integer, Supplier<Calculator>> calculationTypeMap = new HashMap<>();

    @Autowired
    ContractOneType contractOneType;

    @Autowired
    ContractTwoType contractTwoType;

    static {
        calculationTypeMap.put(1, contractOneType);
        calculationTypeMap.put(2, contractTwoType);
    }

    public Calculator getCalculationMethod(Integer type) {
        Supplier<Calculator> method = calculationTypeMap.get(type);
        if (method != null) {
            return method.get();
        }
        throw new IllegalStateException("Type not found");
    }

}
@Component
public class ContractOneType implements Calculator {

    @Autowired
    private ContractRepository contractRepository;

    public ResponseDTO calculate(Request request) {

        ResponseDTO responseDTO = new ResponseDTO();

        Contract contract = contractRepository.findById(request.getId()).orElseThrow(() -> new NotFoundException("id not found"));

        //some calculations here with the contract

        return responseDTO;

    }

}
public interface Calculator {
    ResponseDTO calculate(Request Request);

}

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