Java 通过字段“服务”表达的不满意的依赖关系：没有符合条件的 bean 类型
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时间：2020-08-11 20:12:18 来源:igfitidea点击:
Unsatisfied dependency expressed through field 'service': No qualifying bean of type
提问by Hamada Ibrahim
Hi guys can any body help me I am creating new project using spring mvc and hibernate This is my repository
大家好，任何人都可以帮助我我正在使用 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);
}
and this is the implementation
这是实现
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;
}
}
also this is the service interface
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);
}
and this is the service implementation
这是服务实现
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);
}
}
this is the controller
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";
}
}
when i run the program i got this error
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.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.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)
this is my web.xml file
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>
and this is spring configuration
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>
also this is hibernate configuration
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>
Can anybody help me?
有谁能够帮助我？
回答by Lê Th?
In the configuration of component-scan you need to include com.cs545.ecom.service
So you should have
在 component-scan 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"/>
回答by vipin cp
Change context:component-scanin web.xmlas shown below
变化context:component-scan中web.xml，如下所示
<context:component-scan base-package="com.cs545.ecom"/>
Spring will register all the beans defined inside the given package. In your case only controller bean will be registered and service beans will not.
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，不会注册服务 bean。
回答by Supun Wijerathne
As mentioned in other answers also, you have to configure classpath scanning for your bean to make sure that it can be autowired into some other bean.
正如其他答案中所提到的，您必须为 bean 配置类路径扫描，以确保它可以自动装配到其他 bean 中。
Other than that, this error can be caused by several other problems. The main reason for this is the IOC container has not initialized a bean of type SomeTypewhen the run-time tries to autowire that type of a bean into some other class.
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SomeType当运行时尝试将该类型的 bean 自动装配到某个其他类时，IOC 容器尚未初始化该类型的 bean。
This articlesummarizes the possible mistakes that can cause this.
该文章总结了可能的错误可能导致此。
回答by Cosmin Mavrichi
I had a similar problem and the fault was with Mockito's:
我有一个类似的问题，错误在于 Mockito 的：
given(method(Class.class)).thenReturn();
I had to use the any(Class.class) because my method wasn't calling the exact class so the return would've triggered.
我不得不使用 any(Class.class) 因为我的方法没有调用确切的类所以返回会被触发。
