Question

目前我在控制器和服务层之间遇到Autowire配置问题。

我无法追查错误。

简单日志信息

    SEVERE:   Exception while loading the app
    SEVERE:   Undeployment failed for context /OTT
    SEVERE:   Exception while loading the app : java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: org.apache.catalina.LifecycleException: org.springframework.beans.factory.NoSuchBeanDefinitionException: 
No qualifying bean of type [com.ott.service.EmployeeService] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {}

下面我还给出了Controller和Service Layer代码以及dispatcher-servlet.xml

控制器

package com.ott.controller;

import com.ott.service.EmployeeService;
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.RequestMapping;

    /**
     *
     * @author SPAR
     */
    @Controller
    public class AdminController {

        private EmployeeService employeeService;

        @RequestMapping("/employee")
        public String employee(){
            this.employeeService.fetchAll();
            return "employee";
        }

        @Autowired(required = true)
        @Qualifier(value="employeeService")
        public void setEmployeeService(EmployeeService empService) {
            this.employeeService = empService;
        }

    }

服务界面

package com.ott.service;

import com.ott.hibernate.Employee;
import java.util.List;

/**
 *
 * @author SPAR
 */
public interface EmployeeService {

     List<Employee> fetchAll();


}

服务接口Impl

package com.ott.service;

import com.ott.dao.EmployeeDAO;
import com.ott.hibernate.Employee;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

/**
 *
 * @author SPAR
 */
@Service
public class EmployeeServiceImpl implements EmployeeService{

    private EmployeeDAO employeeDAO;

    @Override
    @Transactional(readOnly = true)
    public List<Employee> fetchAll() {

        List<Employee> employees = employeeDAO.fetchAll();
        for (Employee employee : employees) {

            System.out.println("Name : "+employee.getFirst_Name() +" "+ employee.getLast_Name());

            System.out.println("Email Id : "+employee.getEmail_Id());
        }

        return employees;
    }

    @Autowired(required = true)
    @Qualifier(value="employeeDAO")
    public void setEmployeeDAO(EmployeeDAO empDAO) {
        this.employeeDAO = empDAO;
    }
}

分派器-servlet.xml中

 <?xml version='1.0' encoding='UTF-8' ?>
    <!-- was: <?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:p="http://www.springframework.org/schema/p"
           xmlns:aop="http://www.springframework.org/schema/aop"
           xmlns:tx="http://www.springframework.org/schema/tx"
           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-4.0.xsd
           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
           http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.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">

        <context:component-scan base-package="com.ott.controller"/>
        <context:component-scan base-package="com.ott.hibernate"/>
        <context:component-scan base-package="com.ott.service"/>
        <context:component-scan base-package="com.ott.dao"/>

        <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping"/>
        <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter"/>

        <mvc:resources mapping="/resources/**" location="/resources/" />

         <bean id="tilesConfigurer" class="org.springframework.web.servlet.view.tiles3.TilesConfigurer">
            <property name="definitions">
                <list>
                    <value>/WEB-INF/tiles-def/general-layout.xml</value>
                </list>
            </property>
        </bean>

        <bean id="viewResolverTiles" class="org.springframework.web.servlet.view.UrlBasedViewResolver">
            <property name="viewClass" value="org.springframework.web.servlet.view.tiles3.TilesView"/>
        </bean> 

        <mvc:annotation-driven />

        <bean
          class="org.springframework.web.servlet.view.InternalResourceViewResolver">
          <property name="prefix">
            <value>/WEB-INF/pages/</value>
          </property>
          <property name="suffix">
            <value>.jsp</value>
          </property>
        </bean>
    </beans>

Answer 1

伙计们我发现了这个问题

我刚尝试在员工服务中添加限定符名称，最终解决了我的问题。

@Service("employeeService")

public class EmployeeServiceImpl implements EmployeeService{

}

Answer 2

我相信@Service您必须添加限定符名称，如下所示：

@Service("employeeService")应解决您的问题

或@Service后，您应添加@Qualifier annontion，如下所示：

@Service
@Qualifier("employeeService")

Answer 3

您不必提供名称和限定符。如果设置名称，那就是在上下文中注册bean的名称。如果您没有为您的服务提供名称，则会根据BeanNameGenerator将其注册为非大写的非限定类名称。因此，在您的情况下，实施将注册为employeeServiceImpl。因此，如果您尝试使用该名称进行自动装配，则应直接解决。

private EmployeeService employeeServiceImpl;

@RequestMapping("/employee")
public String employee() {
    this.employeeService.fetchAll();
    return "employee";
}

@Autowired(required = true)
public void setEmployeeService(EmployeeService employeeServiceImpl) {
    this.employeeServiceImpl = employeeServiceImpl;
}

如果存在多个相同类型的bean并且您希望为各种目的自动装配不同的实现bean，则使用

@Qualifier。

Answer 4

如果您只有一个EmployeeService类型的bean，并且接口EmployeeService没有其他实现，您可以简单地将＆＃34; @Service＆＃34;在EmployeeServiceImpl和＆＃34; @ Autowire＆＃34;之前在setter方法之前。否则，您应该将特殊bean命名为@Service（＆＃34; myspecial＆＃34;）并在setter方法之前放置＆＃34; @autowire @Qualifier（＆＃34; myspecial＆＃34;）。

Answer 5

在您的控制器类中，只需添加@ComponentScan（＆＃34; package＆＃34;）注释。在我的情况下，包名称是com.shoppingcart.So我将代码编写为@ComponentScan（＆＃34; com.shoppingcart＆＃34;），它对我有用。

Answer 6

您忘记了服务类中的@Service注释。

Answer 7

@Service：它告诉特定的类是客户端的服务。服务类主要包含业务逻辑。如果包中有多个Service类而不是提供@Qualifier，否则它不应该要求@Qualifier。

案例1：

情况2：

@Service("employeeService")
public class EmployeeServiceImpl implements EmployeeService{
}

两种情况都在起作用......

Answer 8

只需在服务实现类中添加带有限定符服务名称的注释：

@Service("employeeService")
@Transactional
public class EmployeeServiceImpl implements EmployeeService{
}

Answer 9

缺少＆＃39;工具＆＃39; impl类中的关键字也可能是问题

@Autowired - 没有找到依赖于至少1个bean的类型的限定bean

9 个答案: