想要一些建议来清理一系列 if 语句答案

【问题标题】：Would like some suggestions to clean up a series of if statements想要一些建议来清理一系列 if 语句
【发布时间】：2021-04-19 14:45:29
【问题描述】：

我有一种方法可以进行大量验证，并且正在失控。我将不胜感激有关如何最好地清理此方法的任何建议。我正在使用 Java 11，此方法是 Spring Boot 微服务的一部分。

public void validateRequest(DepositRequest depositRequest, String transferId, String userId) {
    if (!Arrays.asList("REALTIME_PAYMENT", "ACCOUNT_PAYMENT").contains(depositRequest.creditTransfer()
            .getTransferInformation().getValue())) {
        logError(depositRequest, participantUserId, etransferId, INVALID_ACCOUNT_NUMBER);
        throw new ServerValidationException(INVALID_ACCOUNT_NUMBER, PAYMENT);
    }

    if (depositRequest.creditTransfer().getGroupHeader().getSettlementInformation().getClearingSystem() == null) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "proprietary");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }

    if (depositRequest.creditTransfer().getGroupHeader().getInstructing()
            .getInstitutionIdentification().getMemberIdentification() == null) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "member_identification");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }

    if (depositRequest.creditTransfer().getGroupHeader().getInstructed()
            cialInstitutionIdentification().getMemberIdentification() == null) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "member_identification");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }

    if (depositRequest.creditTransfer().getTransferInformation().getCreditor().getName() == null) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "creditor.name");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }

    if (depositRequest.creditTransfer().getTransferInformation().getDebtor().getName() == null) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "debtor.name");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }

    if (depositRequest.authorization() != null) {
        if (depositRequest.authorization().getToken() == null ||
                authorization().getToken().length() < 1 ||
                authorization().getToken().length() > 35) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "participant_authorization_token");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
        }
    }

    if (!isCreditorAccountIdentificationValid(depositRequest.creditTransfer().getTransferInformation().getIdentification())) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "identification");
        throw new ServerValidationException(INVALID_ACCOUNT_INFO, PAYMENT);
    }

    if (!depositRequest.creditTransfer().getTransferInformation().getSettlementDate().equals(LocalDate.now())) {
        logSchemaValidationError(depositRequest, etransferId, participantUserId, "settlement_date");
        throw new ServerValidationException(SCHEMA_VALIDATION_ERROR, PAYMENT);
    }
}

【问题讨论】：

标签： java refactoring

【解决方案1】：

简单的代码就是好的代码。您当前的代码易于理解和维护。所以我不一定会急于改变它。但如果你愿意，你可以：

在单独的私有方法中进行每个验证，并在主验证方法中调用每个方法

public void validateRequest(DepositRequest depositRequest, String transferId, String userId) {
 validateAccountNumber(depositRequest,transferId, userId);
    ...
}

private void validateAccountNumber(DepositRequest depositRequest, String transferId, String userId) {
    ...
}

你可以看中并创建一个验证器接口

public interface Validator {
     void validate(DepositRequest depositRequest, String transferId, String userId);
}

public class AccountIDValidator implements Validator {
     public void validate(DepositRequest depositRequest, String transferId, String userId){
          ...
      }
 }

然后你为每个验证创建这个接口的实例，然后你把它们放在一个列表中，这样你的验证就变成了

   List<Validator> validators=Arrays.asList(new AccountIDValidator(),...);

   public void validateRequest(DepositRequest depositRequest, String transferId, String userId) {
       for (Validator v:validators){
          v.validate();
       }
   }

【讨论】：