Spring 3.1自动装配在自定义约束验证器中不起作用 [英] Spring 3.1 Autowiring does not work inside custom constraint validator

问题描述

我在自定义约束验证器中的bean自动装配有问题。没有使用Spring的LocalValidatorFactoryBean给出约束验证器实例。
JSR-303提供程序是hibernate-validator 4.2.0.Final。

I have an issue with bean autowiring inside a custom constraint validator. A constraint validator instance is not given using Spring's LocalValidatorFactoryBean. The JSR-303 provider is hibernate-validator 4.2.0.Final.

Spring配置摘录：

Spring configuration excerpt :

<!-- JSR 303 validation -->
<bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean" />
<bean class="org.springframework.validation.beanvalidation.MethodValidationPostProcessor"/> 

自定义约束验证器：

import javax.validation.ConstraintValidator;
import javax.validation.ConstraintValidatorContext;

import org.springframework.beans.factory.annotation.Autowired;

import com.model.Subject;
import com.services.SomeTypeService;

public class ReadOnlyValidator implements ConstraintValidator<ReadOnly, String> {

@Autowired
private SomeTypeService someTypeService;

@Override
public void initialize(ReadOnly constraintAnnotation) { }

@Override
public boolean isValid(String type, ConstraintValidatorContext context) {
    try {
         if (null != type) {
                        return !someTypeService.isReadonly(type);
                     }
    } catch (Exception e) {
        e.printStackTrace();
    }

    return false;
}
}

注释：

import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.*;

import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import javax.validation.Constraint;
import javax.validation.Payload;

@Target( { METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER } )
@Retention(RUNTIME)
@Constraint(validatedBy = ReadOnlyValidator.class)
@Documented
public @interface ReadOnly {
String message() default "{constraints.subjecttype.readonly}";
public abstract Class<?>[] groups() default {};
public abstract Class<? extends Payload>[] payload() default {};
}

SomeService：

SomeService:

 @Validated
 public interface SomeService {
    ...
    public void updateType(@ReadOnly String type) throws SomeException;
    ...
 }

SomeServiceImpl：

SomeServiceImpl :

 @Service
 public class SomeServiceImpl implements SomeService {
  ...
    public void updateType(String type) throws SomeException {
     // do something
    }
  ...
 }

SomeTypeService是另一个不依赖SomeService的@Service带注释的Bean ...

SomeTypeService is another @Service annotated bean that does not depend on SomeService ...

问题是我得到了NPE，因为自动装配不起作用。

The problem is that I get an NPE as autowiring does not work; someone else is managing the custom validator instances and not Spring ...

在此先感谢任何类型的建议。

Thanks in advance for any type of advice.

推荐答案

发现了问题。 MethodValidationPostProcessor和mvc：annotation驱动的声明必须使用相同的验证器 bean引用：

Found the problem. The same "validator" bean reference must be used by MethodValidationPostProcessor and mvc:annotation-driven declaration:

service-context.xml

<!-- JSR 303 validation -->
<bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean"/>
<bean class="org.springframework.validation.beanvalidation.MethodValidationPostProcessor">
    <property name="validator" ref="validator"/>
</bean>
    ...

dispatcher-servlet.xml

...
<mvc:annotation-driven validator="validator" />
...

这篇关于Spring 3.1自动装配在自定义约束验证器中不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！