使用 Java Bean 验证验证对象图/集合时的自定义消息

Question

遵守以下代码。 DealerLot 有一个 carInventory，它由汽车组成，所有汽车都包含一个引擎。当前dealerlot 有两辆汽车在库存中，并且在验证时，汽车的一个引擎未能通过验证。但是，错误消息仅包含有关引擎的信息。在消息中包含 carName 的最简洁方式是什么？

public class main {

@Data
@AllArgsConstructor
static class Engine {
    @Pattern(regexp="V.*", message="Engine Name must start with a V! You provided ${validatedValue}")
    private String engineName;
}

@Data
@AllArgsConstructor
static class Car {
    private String carName;
    @Valid
    private Engine engine;
}

@Data
@AllArgsConstructor
static class DealerLot {
    @Valid
    private List<Car> carInventory;
}

public static void main(String args[]){
    ValidatorFactory factory = Validation.buildDefaultValidatorFactory();
    Validator validator = factory.getValidator();

    Engine engine1 = new Engine("VQ35DE");
    Car car1 = new Car("Nissan 350z", engine1);
    Engine engine2 = new Engine("2JZ-GTE");
    Car car2 = new Car("Toyota Supra", engine2);
    DealerLot dealerLot1 = new DealerLot(Arrays.asList(car1, car2));

    Set<ConstraintViolation<DealerLot>> i = validator.validate(dealerLot1);
    for (ConstraintViolation<DealerLot> v : i) {
        System.out.println(v.getMessage());
    };
}}

输出：

Engine Name must start with a V! You provided 2JZ-GTE

我希望输出看起来像下面这样：

Toyota Supra, Engine Name must start with a V! You provided 2JZ-GTE

如果没有这种程度的清晰度，确定哪些汽车存在问题可能会非常混乱。

仅供参考，这些是我在示例中使用的依赖项的版本：

compile group: 'org.hibernate.validator', name: 'hibernate-validator', version: '6.0.17.Final'
compile group: 'org.glassfish', name: 'javax.el', version: '3.0.1-b11'
implementation group: 'org.projectlombok', name: 'lombok', version: "1.18.4"
compile group: 'javax.validation', name: 'validation-api', version: '2.0.1.Final'

Answer 1

就像 hfontanez 所说，您需要将验证移至Car。您仍然可以使用自定义验证注释（我们称之为ValidCarEngine）和验证器来获取引擎名称上报告的错误。

public class ValidCarEngineValidator implements ConstraintValidator<ValidCarEngine, Car> {

private static final Pattern ENGINE_NAME_PATTERN = Pattern.compile("V.*");

@Override
public boolean isValid(Car car, ConstraintValidatorContext context) {
    if (car == null || car.getEngine() == null || car.getEngine().getEngineName() == null) {
        return true; // use @NotNull if needed
    }
    String carName = car.getCarName();
    String engineName = car.getEngine().getName();

    if (Pattern.matcher(engineName).matches()) {
        return true;
    }
    // Disable the out-of-the-box error on the Car
    constraintValidatorContext.disableDefaultConstraintViolation();

    String message = carName + ", Engine Name must start with a V! You provided " + engineName;
    constraintValidatorContext.buildConstraintViolationWithTemplate(message)
            .addPropertyNode("engine")
            .addPropertyNode("engineName")
            .addConstraintViolation();
    return false;
}

这对所有汽车都使用硬编码模式，但您甚至可以添加从汽车类型/名称到模式的映射（只需确保使用默认值，如果没有映射，则返回 true）。