Question

我知道这个问题已经被问了很多，我冒了一个双重（或三重或四重）的话题，但建议的解决方案似乎对我不起作用。

我遇到了很多可怕的无法自动发送错误的问题。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是什么。

这是我目前的设置： 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;
    }
}

弹簧mvc.xml

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

错误：

SEVERE：将上下文初始化事件发送到类org.springframework.web.context.ContextLoaderListener的侦听器实例的异常 org.springframework.beans.factory.BeanCreationException：使用名称＆＃39; projectRestController创建bean时出错＆＃39;：注入自动连接的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService;嵌套异常是org.springframework.beans.factory.BeanCreationException：使用名称＆＃39; projectService＆＃39;创建bean时出错：注册自动装配的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo;嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到[be.italent.repo.ProjectRepo]类型的限定bean：预期至少有1个bean符合此依赖项的autowire候选者。依赖注释：{@ org.springframework.beans.factory.annotation.Autowired（required = true）} 在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:292）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1185）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:537）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:475） at org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:304）在org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:228）在org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:300）在org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:195） at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons（DefaultListableBeanFactory.java:700）在org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:760） at org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:482） at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext（ContextLoader.java:403）在org.springframework.web.context.ContextLoader.initWebApplicationContext（ContextLoader.java:306）在org.springframework.web.context.ContextLoaderListener.contextInitialized（ContextLoaderListener.java:106） at org.apache.catalina.core.StandardContext.listenerStart（StandardContext.java:5068） at org.apache.catalina.core.StandardContext.startInternal（StandardContext.java:5584）在org.apache.catalina.util.LifecycleBase.start（LifecycleBase.java:147）在org.apache.catalina.core.ContainerBase $ StartChild.call（ContainerBase.java:1572）在org.apache.catalina.core.ContainerBase $ StartChild.call（ContainerBase.java:1562） at java.util.concurrent.FutureTask.run（FutureTask.java:266）在java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1142） at java.util.concurrent.ThreadPoolExecutor $ Worker.run（ThreadPoolExecutor.java:617）在java.lang.Thread.run（Thread.java:745）引起：org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.services.ProjectService be.italent.controllers.ProjectRestController.projectService;嵌套异常是org.springframework.beans.factory.BeanCreationException：使用名称＆＃39; projectService＆＃39;创建bean时出错：注册自动装配的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo;嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到[be.italent.repo.ProjectRepo]类型的限定bean：预期至少有1个bean符合此依赖项的autowire候选者。依赖注释：{@ org.springframework.beans.factory.annotation.Autowired（required = true）} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:508）在org.springframework.beans.factory.annotation.InjectionMetadata.inject（InjectionMetadata.java:87）在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:289） ......还有22个由以下原因引起：org.springframework.beans.factory.BeanCreationException：创建名称为＆＃39; projectService＆＃39;的注册：自动连接的依赖项失败;嵌套异常是org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo;嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到[be.italent.repo.ProjectRepo]类型的限定bean：预期至少有1个bean符合此依赖项的autowire候选者。依赖注释：{@ org.springframework.beans.factory.annotation.Autowired（required = true）} 在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:292）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1185）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:537）在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:475） at org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:304）在org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:228）在org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:300）在org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:195）在org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates（DefaultListableBeanFactory.java:1014） at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency（DefaultListableBeanFactory.java:957）在org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency（DefaultListableBeanFactory.java:855）在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:480） ......还有24个引起：org.springframework.beans.factory.BeanCreationException：无法自动装配字段：private be.italent.repo.ProjectRepo be.italent.services.ProjectService.projectRepo;嵌套异常是org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到[be.italent.repo.ProjectRepo]类型的限定bean：预期至少有1个bean符合此依赖项的autowire候选者。依赖注释：{@ org.springframework.beans.factory.annotation.Autowired（required = true）} at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:508）在org.springframework.beans.factory.annotation.InjectionMetadata.inject（InjectionMetadata.java:87）在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:289） ......还有35个由以下原因引起：org.springframework.beans.factory.NoSuchBeanDefinitionException：没有为依赖项找到[be.italent.repo.ProjectRepo]类型的限定bean：期望至少有1个bean符合此依赖项的autowire候选者。依赖注释：{@ org.springframework.beans.factory.annotation.Autowired（required = true）} at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException（DefaultListableBeanFactory.java:1100）在org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency（DefaultListableBeanFactory.java:960）在org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency（DefaultListableBeanFactory.java:855）在org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor $ AutowiredFieldElement.inject（AutowiredAnnotationBeanPostProcessor.java:480） ......还有37个

有任何帮助吗？谢谢！

解决方案

将此添加到我的spring-mvc.xml：

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

...

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

Answer 1

当初始化应用程序上下文时出现问题时，Spring经常会给出这些长堆栈跟踪。通常，您可以通过查看堆栈跟踪的底部来找出最终原因。

在您的情况下，您会在底部看到此错误消息：

org.springframework.beans.factory.NoSuchBeanDefinitionException：找不到[be.italent.repo.ProjectRepo]类型的限定bean

这意味着Spring找不到类型为public class FirstFragment extends Fragment { EditText emailText; EditText passText; Button loginButton; TextView registerView; int counter=0; public FirstFragment() { // Required empty public constructor } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View view = inflater.inflate(R.layout.fragment_first, container, false); emailText = (EditText) view.findViewById(R.id.emailText); passText = (EditText) view.findViewById(R.id.passwordText); loginButton = (Button) view.findViewById(R.id.LoginButton); registerView = (TextView) view.findViewById(R.id.RegisterView); final TextInputLayout nameText = new TextInputLayout(getActivity()); final TextInputLayout DeptText = new TextInputLayout(getActivity()); final EditText phoneNumber = new EditText(getActivity()); final Button registerButton = new Button(getActivity()); final LinearLayout layout = (LinearLayout)view.findViewById(R.id.fragmentLayout); phoneNumber.setInputType(InputType.TYPE_CLASS_PHONE); LinearLayout.LayoutParams parameters1 = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT) ; nameText.setLayoutParams(parameters1); DeptText.setLayoutParams(parameters1); phoneNumber.setLayoutParams(parameters1); LinearLayout.LayoutParams parameters2 = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT) ; parameters2.gravity = Gravity.CENTER; registerButton.setLayoutParams(parameters2); nameText.setHint("Enter Name"); DeptText.setHint("Enter Department"); phoneNumber.setHint("Enter Phone Number"); registerButton.setText("Register"); registerView.setTextColor(Color.BLUE); registerView.setTextSize(17); registerView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { counter++; if(counter==1) { layout.addView(nameText,1 ); layout.addView(DeptText, 2); layout.addView(phoneNumber,3); layout.removeView(loginButton); layout.addView(registerButton,5); registerView.setText("Already signed Up? login"); } else{ layout.removeView(nameText); layout.removeView(DeptText); layout.removeView(phoneNumber); layout.removeView(registerButton); layout.addView(loginButton,2); registerView.setText("New User? Sign Up"); counter=0; } } }); return view; } }的bean。

您的ProjectRepo存储库接口位于包ProjectRepo中，这是be.italent.repo的子包，它是组件扫描的，所以问题不在于它是在错误的包中。

您是否忘记启用Spring Data JPA？

当您使用XML配置时（正如您现在所做的那样），您必须在配置文件中包含be.italent XML标记：

repositories

使用JavaConfig时，可以使用注释：

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

    <!-- Tell Spring Data JPA where your repository interfaces are -->
    <jpa:repositories base-package="be.italent.repo" />

    <!-- ... -->
</beans>

Answer 2

问题在ProjectRestController.java中您已将@Autowired用于ProjectService 1）

删除@Autowired注释。
从projectService中获取和获取setter。
在spring.xml中为ProjectService设置Bean

现在运行您的应用程序。它对我有用。

注入自动装配的依赖项失败，无法自动装配字段

2 个答案: