Spring @Autowire注释存在问题（null）

我在验证器类中自动连接的两个服务有问题。服务工作正常，因为在我的控制器中是自动连接的。我有一个applicationContext.xml文件和MyApp-servlet.xml文件。我的基本包是es.unican.meteo，我的包es.unican.meteo.validator有问题。包es.unican.meteo.controller和es.unican.meteo.service可以正确地自动连接服务

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:p="http://www.springframework.org/schema/p"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

....
some beans
...
</beans>

---

确保您对该类进行了注释，以便Spring将其作为bean进行处理。自动连接只能发生在DI容器管理的bean/类上

添加

@Component

将导致Spring的组件扫描拾取该类，从而导致

ResetPasswordValidation

成为bean。此时，应该可以自动连接字段

@Component
public class ResetPasswordValidation  implements Validator

---

凯文，你的观点很有趣。现在eclipse项目检测到我在验证类中有自动连接的元素，但它没有注入服务。属性仍然为空，也许我需要更多的东西吗？是的@Kevin，控制器类中的服务工作正常。我已经添加了与ResetPasswordValidationI发现错误@kevin对应的日志。我正在用new（…）创建ResetPasswordValidation的实例；现在，我的控制器中有一个自动连接的验证器属性。非常感谢您的回答，因为组件是必需的@曼努克很高兴我能帮忙。我以前在new上也犯过错误。我会看看你的博客：）

package es.unican.meteo.validator;


import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;

import es.unican.meteo.model.User;
import es.unican.meteo.service.MessageService;
import es.unican.meteo.service.UserService;

public class ResetPasswordValidation  implements Validator{

    @Autowired
    private UserService userService;

    @Autowired
    private MessageService messageService;

    public boolean supports(Class<?> clazz) {
        return User.class.equals(clazz);
    }

    public void validate(Object target, Errors errors) {
        User user = (User)target; 
        if(userService.getUserByEmail(user.getEmail())==null){
            errors.rejectValue("email", messageService.getMessage("app.error.nonexistentemail"));
        }
    }
}

12:48:50,697 DEBUG main support.DefaultListableBeanFactory:217 - Creating shared instance of singleton bean 'resetPasswordValidation'
12:48:50,697 DEBUG main support.DefaultListableBeanFactory:430 - Creating instance of bean 'resetPasswordValidation'
12:48:50,701 DEBUG main annotation.InjectionMetadata:60 - Found injected element on class [es.unican.meteo.validator.ResetPasswordValidation]: AutowiredFieldElement for private es.unican.meteo.service.UserService es.unican.meteo.validator.ResetPasswordValidation.userService
12:48:50,702 DEBUG main annotation.InjectionMetadata:60 - Found injected element on class [es.unican.meteo.validator.ResetPasswordValidation]: AutowiredFieldElement for private es.unican.meteo.service.MessageService es.unican.meteo.validator.ResetPasswordValidation.messageService
12:48:50,702 DEBUG main support.DefaultListableBeanFactory:504 - Eagerly caching bean 'resetPasswordValidation' to allow for resolving potential circular references
12:48:50,707 DEBUG main annotation.InjectionMetadata:85 - Processing injected method of bean 'resetPasswordValidation': AutowiredFieldElement for private es.unican.meteo.service.UserService es.unican.meteo.validator.ResetPasswordValidation.userService

@Component
public class ResetPasswordValidation  implements Validator