通过字段“服务”表示不满足的依赖关系：没有符合条件的 bean 类型

Question

我正在使用 spring mvc 和 hibernate 创建新项目。这是我的存储库：

package com.cs545.ecom.repository;

import java.util.List;

import com.cs545.ecom.domain.Product;

public interface ProductDAO {
    List<Product> getAllProducts();

    Product getProductById(int id);

    Product getProductByName(String name);

    Product addNewProduct(Product product);

    Product updateProduct(int productId, Product product);

}

这就是实现

package com.cs545.ecom.repository.impl;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.springframework.stereotype.Repository;

import com.cs545.ecom.domain.Product;
import com.cs545.ecom.repository.ProductDAO;

@Repository
public class ProductDAOimpl implements ProductDAO{

    SessionFactory sessionFactory=new Configuration().configure().buildSessionFactory();
    public List<Product> getAllProducts() {
        // TODO Auto-generated method stub
        return null;
    }

    public Product getProductById(int id) {
        // TODO Auto-generated method stub
        return null;
    }

    public Product getProductByName(String name) {
        // TODO Auto-generated method stub
        return null;
    }

    public Product addNewProduct(Product product) {
        Product productSaved=new Product();
        Session session=sessionFactory.openSession();
        session.beginTransaction();
        productSaved=(Product)session.save(product);
        session.getTransaction().commit();
        session.close();
        return productSaved;
    }

    public Product updateProduct(int productId, Product product) {
        // TODO Auto-generated method stub
        return null;
    }

}

这也是服务接口

package com.cs545.ecom.service;

import com.cs545.ecom.domain.Product;

public interface ProductService {
    Product addNewProduct(Product product);
}

这就是服务实现

package com.cs545.ecom.service.impl;



import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.stereotype.Service;

import com.cs545.ecom.domain.Product;
import com.cs545.ecom.repository.ProductDAO;
import com.cs545.ecom.service.ProductService;
@Service
public class ProductServiceImpl implements ProductService {
    @Autowired
    private ProductDAO repository;

    public Product addNewProduct(Product product) {
        return repository.addNewProduct(product);
    }

}

这是控制器

package com.cs545.ecom.controller;



import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

import com.cs545.ecom.domain.Category;
import com.cs545.ecom.domain.Product;
import com.cs545.ecom.repository.ProductDAO;
import com.cs545.ecom.service.ProductService;

@Controller
public class ProductController {
    @Autowired
    public ProductService service;
    
    @RequestMapping("/")
    public String start() {
        return "UI/jsp/product";
    }
    @RequestMapping("/addproduct")
    public String addNewProduct(Model model){
    //  Product product=service.addNewProduct(new Product("Apple iphone", "gfgfg", "Amazing Iphone ", new Category()));
        //Product product=new Product("Apple iphone", "gfgfg", "Amazing Iphone ", new Category());
        
        //model.addAttribute("product",product);
        return "UI/jsp/product";
    }
}

当我运行程序时出现此错误

HTTP Status 500 - Servlet.init() for servlet Dispatcher Servlet threw exception


type Exception report

message Servlet.init() for servlet Dispatcher Servlet threw exception

description The server encountered an internal error that prevented it from fulfilling this request.

exception
javax.servlet.ServletException: Servlet.init() for servlet Dispatcher Servlet threw exception
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)


root cause
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'productController': Unsatisfied dependency expressed through field 'service': No qualifying bean of type [com.cs545.ecom.service.ProductService] found for dependency [com.cs545.ecom.service.ProductService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.cs545.ecom.service.ProductService] found for dependency [com.cs545.ecom.service.ProductService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:569)
    org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:775)
    org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541)
    org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:668)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:634)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:682)
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:553)
    org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:494)
    org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)


root cause
org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [com.cs545.ecom.service.ProductService] found for dependency [com.cs545.ecom.service.ProductService]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1403)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1056)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1018)
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:566)
    org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
    org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:775)
    org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861)
    org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541)
    org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:668)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:634)
    org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:682)
    org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:553)
    org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:494)
    org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:528)
    org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1099)
    org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:672)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1520)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1476)
    java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.lang.Thread.run(Unknown Source)

这是我的 web.xml 文件：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    
    <servlet>
        <servlet-name>Dispatcher Servlet</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <!--init-param is not needed when followed default naming convention for configuration file "DefaultServlet-servlet.xml"-->
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>
                /WEB-INF/dispatcher-config.xml
            </param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
  
    <servlet-mapping>
        <servlet-name>Dispatcher Servlet</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
  
    <session-config>
        <session-timeout>
            30
        </session-timeout>
    </session-config>
</web-app>

这是弹簧配置

<?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:mvc="http://www.springframework.org/schema/mvc"
       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-4.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
    ">
  <mvc:annotation-driven/>
  <mvc:resources mapping="/resources/**" location="/resources/"/>
  <context:component-scan base-package="com.cs545.ecom.controller"/>
  
  <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/views/" />
    <property name="suffix" value=".jsp"/>
  </bean>
  <bean id= "messageSource"
class="org.springframework.context.support.ResourceBundleMessageSource">
<property name="basename" value="messages"/>
</bean>

</beans>

这也是休眠配置

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
    <session-factory>
        <property name="hibernate.bytecode.use_reflection_optimizer">false</property>
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.password">111111</property>
        <property name="hibernate.connection.url">jdbc:mysql://localhost:3338/waaProject</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <property name="show_sql">true</property>
        <property name="hbm2ddl.auto">update</property>
        <mapping class="com.cs545.ecom.domain.Product"></mapping>
    </session-factory>
</hibernate-configuration>

Answer 1

在组件扫描的配置中你需要包含com.cs545.ecom.service
所以你应该有

<context:component-scan base-package="com.cs545.ecom.controller, com.cs545.ecom.service"/>

Answer 2

将context:component-scan改成web.xml如下图

  <context:component-scan base-package="com.cs545.ecom"/>

Spring 将注册给定包中定义的所有 bean。在您的情况下，只会注册控制器 bean，而不会注册服务 bean。

Answer 3

正如其他答案中提到的，您必须为您的 bean 配置类路径扫描，以确保它可以自动装配到其他某个 bean。

除此之外，此错误可能是由其他几个问题引起的。造成这种情况的主要原因是，当运行时尝试将 SomeType 类型的 bean 自动装配到其他类中时，IOC 容器没有初始化该类型的 bean。

article 总结了可能导致此问题的可能错误。

Answer 4

我遇到了类似的问题，问题出在 Mockito 的问题上：

given(method(Class.class)).thenReturn();

我必须使用 any(Class.class) 因为我的方法没有调用确切的类，所以会触发返回。