Spring项目中的org.springframework.beans.NotWritablePropertyException

Question

我正在尝试使用 CRUD 操作创建一个 Spring 项目。我是 Spring 新手，所以我需要一些帮助-

使用 post 方法提交表单时出现以下错误-

引起：org.springframework.beans.NotWritablePropertyException： bean 类的无效属性“userDao” [com.cjc.service.RegistrationServiceImpl]：Bean 属性 'userDao' 是 不可写或具有无效的 setter 方法。参数类型是否 setter 的返回类型是否匹配 getter 的返回类型？在 org.springframework.beans.BeanWrapperImpl.createNotWritablePropertyException(BeanWrapperImpl.java:231) 在 org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:423) 在 org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:280) 在 org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:95) 在 org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:75) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1514) ... 47 更多

2019 年 1 月 23 日上午 9:01:09 org.apache.catalina.core.StandardWrapperValve 调用 SEVERE：为 servlet spring 分配异常 org.springframework.beans.NotWritablePropertyException：无效 bean 类的属性“userDao” [com.cjc.service.RegistrationServiceImpl]：Bean 属性 'userDao' 是 不可写或具有无效的 setter 方法。参数类型是否 setter 的返回类型是否匹配 getter 的返回类型？在 org.springframework.beans.BeanWrapperImpl.createNotWritablePropertyException(BeanWrapperImpl.java:231) 在 org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:423) 在 org.springframework.beans.AbstractNestablePropertyAccessor.setPropertyValue(AbstractNestablePropertyAccessor.java:280) 在 org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:95) 在 org.springframework.beans.AbstractPropertyAccessor.setPropertyValues(AbstractPropertyAccessor.java:75) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1514) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1226) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) 在 org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:305) 在 org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) 在 org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:301) 在 org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:196) 在 org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1192) 在 org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1116) 在 org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014) 在 org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:543) 在 org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) 在 org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) 在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) 在 org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:305) 在 org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) 在 org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:301) 在 org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:196) 在 org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772)

请在下面找到相同的 java 文件-

控制器-

package com.cjc.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.cjc.model.User;
import com.cjc.service.RegistrationService;

@Controller
public class RegistrationController {
    @Qualifier("regservice")
    private RegistrationService registrationService;

    public void setRegistrationService(RegistrationService registrationService) {
        this.registrationService = registrationService;
    }

    @RequestMapping(value="/registration", method=RequestMethod.POST)
    public String Registration(@ModelAttribute User u) {
        registrationService.addPerson(u);

        return "RegSuccess";
    }
}

服务-

package com.cjc.service;

import com.cjc.dao.UserDAO;
import com.cjc.model.User;

public class RegistrationServiceImpl implements RegistrationService {

    private UserDAO userDao ;

    public void setUserDao(UserDAO userDao) {
        this.userDao = userDao;
    }



    @Override
    public int addPerson(User u) {
        // TODO Auto-generated method stub

        return 0;
    }

}

DAO 实现-

package com.cjc.dao;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;

import com.cjc.model.User;
import com.cjc.util.HibernateUtil;

public class UserDaoImpl implements UserDAO{

    @Override
    public void addUser(User u) {
        // TODO Auto-generated method stub
        SessionFactory sessionFactory=HibernateUtil.getSessionFactory();
        Session session=sessionFactory.openSession();
        Transaction transaction=session.beginTransaction();

        session.save(u);

        transaction.commit();
    }

    @Override
    public void deleteUser(int id) {
        // TODO Auto-generated method stub

    }

    @Override
    public List<User> getAllUser() {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public User getUserById(int id) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public void updteUser(User u, int id) {
        // TODO Auto-generated method stub

    }

}

Spring-servlet.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="
                http://www.springframework.org/schema/beans
                http://www.springframework.org/schema/beans/spring-beans.xsd
                http://www.springframework.org/schema/context
                http://www.springframework.org/schema/context/spring-context.xsd

                http://www.springframework.org/schema/beans
                http://www.springframework.org/schema/beans/spring-beans.xsd
                http://www.springframework.org/schema/mvc
                http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <mvc:annotation-driven />
    <context:component-scan base-package="com.cjc.controller" />
<bean id="userDAO" class="com.cjc.dao.UserDaoImpl">
    </bean>
    <bean id="regservice" class="com.cjc.service.RegistrationServiceImpl">
        <property name="userDao" ref="userDAO"></property>
    </bean>



    <bean id="viewResolver"
        class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/jsp/"></property>
        <property name="suffix" value=".jsp"></property>

    </bean>

    <bean id="messageSource"
        class="org.springframework.context.support.ResourceBundleMessageSource">

        <property name="basenames" value="application" />
    </bean>
</beans>

请帮我解决问题

Answer 1

您在用户模型中缺少 setter 和 getter。添加 setter 和 getter。

Answer 2

在 UserDao 的 RegistrationServiceImpl 类中添加 getter：

public UserDAO getUserDao() {
    return userDao;
}