自动连接的依赖项注入失败，无法自动连接字段

我知道这个问题已经问了很多，我冒着双重（或三重或四重）主题的风险，但是建议的解决方案似乎对我不起作用。

我遇到了很多无法自动连线的错误。第一次从头开始设置一个完整的Spring项目，所以我真的不知道问题出在哪里。

这是我当前的设置：ProjectRepo：

package be.italent.repo;

import be.italent.model.Project;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

@Repository
public interface ProjectRepo extends JpaRepository<Project, Integer> {

}

ProjectService：

package be.italent.services;

import be.italent.model.Project;
import be.italent.repo.ProjectRepo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class ProjectService {

    @Autowired
    private ProjectRepo projectRepo;

    public List<Project> getAllProjects() {
        return projectRepo.findAll();
    }
}

ProjectRestController：

package be.italent.controllers;

import java.util.ArrayList;
import be.italent.services.ProjectService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import be.italent.model.Project;

@RestController
@RequestMapping("/projects")
public class ProjectRestController {

    @Autowired
    private ProjectService projectService;

    @RequestMapping(method = RequestMethod.GET, produces="application/json")
    public ArrayList<Project> getProjects(){
        ArrayList<Project> c = (ArrayList<Project>) projectService.getAllProjects();

        return c;
    }
}

spring-mvc.xml

...
<context:component-scan base-package="be.italent"></context:component-scan>
...

错误：

严重：将上下文初始化事件发送到类org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException的异常实例：创建名称为'projectRestController'的bean时出错：自动连接依赖项注入失败；嵌套的异常是org.springframework.beans.factory.BeanCreationException：无法自动连线字段：private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService; 嵌套的异常是org.springframework.beans.factory.BeanCreationException：创建名称为'projectService'的bean时出错：自动连接依赖项的注入失败；嵌套的异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：私有be.italent.repo.ProjectRepo be.italent.services.ProjectService。projectRepo; 嵌套的异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有找到类型为[be.italent.repo.ProjectRepo]的合格Bean作为依赖项：至少应有1个符合此依赖项自动候选条件的bean。依赖注释：org.springframework.bean上的org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:292）上的{@ org.springframework.beans.factory.annotation.Autowired（required = true）}。 org.springframework.beans.factory.support上的factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1185）org.springframework.beans.factory.support上的AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:537）266）在java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1142）在java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:617）在java.lang.Thread.run（Thread.java） ：745）由以下原因引起：org.springframework.beans.factory.BeanCreationException：无法自动连线字段：private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService; 嵌套的异常是org.springframework.beans.factory.BeanCreationException：创建名称为'projectService'的bean时出错：自动连接依赖项的注入失败；嵌套的异常是org.springframework.beans.factory.BeanCreationException：无法自动连线字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; 嵌套的异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：找不到依赖项类型为[be.italent.repo.ProjectRepo]的合格bean：期望至少有1个有资格作为此依赖项自动装配候选对象的bean。依赖注释：在org.springframework上的org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:508）上的{@ org.springframework.beans.factory.annotation.Autowired（required = true）}。 org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:289）上的beans.factory.annotation.InjectionMetadata.inject（InjectionMetadata.java:87）... 22更多原因：org.springframeworkbean。 .factory.BeanCreationException：创建名称为'projectService'的bean时出错：自动连接依赖项的注入失败；嵌套的异常是org.springframework.beans.factory.BeanCreationException：无法自动连线字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; 嵌套的异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有找到类型为[be.italent.repo.ProjectRepo]的合格Bean作为依赖项：至少应有1个符合此依赖项自动候选条件的bean。依赖注释：org.springframework.bean上的{@ org.springframework.beans.factory.annotation.Autowired（required = true）}位于org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:292）。 org.springframework.beans的factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1185）。在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement（org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency（DefaultListableBeanFactory.java:855）处的support.DefaultListableBeanFactory.doResolveDependency（DefaultListableBeanFactory.java:957） AutowiredAnnotationBeanPostProcessor.java:480）...还有24个原因：org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo; 嵌套的异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有找到类型为[be.italent.repo.ProjectRepo]的合格Bean作为依赖项：至少应有1个符合此依赖项自动候选条件的bean。相关性注释：{@ org。org.springframework.beans.factors.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:508）上的springframework.beans.factory.annotation.Autowired（required = true）}。 .inject（InjectionMetadata.java:87）at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:289）... 35更多原因：org.springframework.beans.factory.NoSuchBeanDefinitionException：没有资格找到类型为[be.italent.repo.ProjectRepo]的Bean以获得依赖关系：期望至少有1个符合此依赖关系的自动装配候选者。依赖项注释：org.springframework上的{@ org.springframework.beans.factory.annotation.Autowired（required = true）}。

有什么帮助吗？谢谢！

解

将此添加到我的spring-mvc.xml中：

<beans
...
jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

...

<jpa:repositories base-package="be.italent.repo" entity-manager-factory-ref="emf"/>