在我的Spring项目中，我有一个POJO类，该类具有CMYK颜色的属性。 我希望此属性由具有4个浮点数的JSON数组表示。 每个数字必须在0.0到1.0之间。 目前，我正在努力验证此属性。

我已经进行了研究，发现@DecimalMin和@DecimalMax批注不能在Float或float (请参阅此问题的答案)。 因此，我已经放弃了List并改用List 。

这是我精简的POJO类：

public class Settings {

@NotNull

@Size(min = 4, max = 4)

@DecimalMin("0")

@DecimalMax("1")

private List cmykColor;

public List getCmykColor() {

return cmykColor;

}

public void setCmykColor(List cmykColor) {

this.cmykColor = cmykColor;

}

}

这里是JUnit测试：

@RunWith(SpringRunner.class)

@SpringBootTest

public class SettingsTest extends Assert {

@Autowired

private ObjectMapper objectMapper;

@Autowired

private Validator validator; // from org.springframework.validation

private Errors validate(String json) throws IOException {

Settings settings = objectMapper.readValue(json, Settings.class);

Errors errors = new BeanPropertyBindingResult(settings, "settings");

validator.validate(settings, errors);

return errors;

}

@Test

public void testValid() throws IOException {

String json = "{ \"cmykColor\": [0.5, 1.0, 0.3, 0.0] }";

Errors errors = validate(json);

assertEquals(0, errors.getErrorCount());

}

@Test

public void testTooBig() throws IOException {

String json = "{ \"cmykColor\": [0.5, 1.01, 0.3, 0.0] }";

Errors errors = validate(json);

assertEquals(1, errors.getErrorCount());

}

@Test

public void testTooMany() throws IOException {

String json = "{ \"cmykColor\": [0.5, 1.0, 0.3, 0.0, 0.0] }";

Errors errors = validate(json);

assertEquals(1, errors.getErrorCount());

assertNotNull(errors.getFieldError("cmykColor"));

}

}

当我注释掉@DecimalMin("0")和@DecimalMax("1")批注时，所有测试用例均成功，当然testTooBig测试用例除外，后者将依赖于@DecimalMax约束。

但是，当我添加@DecimalMin("0")和@DecimalMax("1")批注时，在所有测试用例上都会出现以下异常，即没有DecimalMax的验证程序来验证List 。

javax.validation.UnexpectedTypeException: HV000030: No validator could be found for constraint 'javax.validation.constraints.DecimalMax' validating type 'java.util.List'. Check configuration for 'cmykColor'

at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.getExceptionForNullValidator(ConstraintTree.java:108)

at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.getInitializedConstraintValidator(ConstraintTree.java:140)

at org.hibernate.validator.internal.engine.constraintvalidation.SimpleConstraintTree.validateConstraints(SimpleConstraintTree.java:55)

at org.hibernate.validator.internal.engine.constraintvalidation.ConstraintTree.validateConstraints(ConstraintTree.java:73)

at org.hibernate.validator.internal.metadata.core.MetaConstraint.doValidateConstraint(MetaConstraint.java:127)

at org.hibernate.validator.internal.metadata.core.MetaConstraint.validateConstraint(MetaConstraint.java:120)

at org.hibernate.validator.internal.engine.ValidatorImpl.validateMetaConstraint(ValidatorImpl.java:533)

at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForSingleDefaultGroupElement(ValidatorImpl.java:496)

at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForDefaultGroup(ValidatorImpl.java:465)

at org.hibernate.validator.internal.engine.ValidatorImpl.validateConstraintsForCurrentGroup(ValidatorImpl.java:430)

at org.hibernate.validator.internal.engine.ValidatorImpl.validateInContext(ValidatorImpl.java:380)

at org.hibernate.validator.internal.engine.ValidatorImpl.validate(ValidatorImpl.java:169)

at org.springframework.validation.beanvalidation.SpringValidatorAdapter.validate(SpringValidatorAdapter.java:104)

at com.oce.spring.domain.SettingsTest.validate(SettingsTest.java:29)

at com.oce.spring.domain.SettingsTest.testTooMany(SettingsTest.java:58)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

...

那么，我应该如何在List正确使用@DecimalMin("0")和@DecimalMax("1") ？