[spring] @Autowired - No qualifying bean of type found for dependency at least 1 bean

Currently I'm facing an issue in Autowire configuration between controller and the service layer.

I'm unable to trace my mistakes.

Simple Log Info

    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: {}

Below I have also given the Controller and Service Layer code and also the dispatcher-servlet.xml

Controller

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;
        }

    }

Service Interface

package com.ott.service;

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

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

     List<Employee> fetchAll();


}

Service Interface 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;
    }
}

Dispatcher-servlet.xml

 <?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>

If you only have one bean of type EmployeeService, and the interface EmployeeService does not have other implementations, you can simply put "@Service" before the EmployeeServiceImpl and "@Autowire" before the setter method. Otherwise, you should name the special bean like @Service("myspecial") and put "@autowire @Qualifier("myspecial") before the setter method.

In your controller class, just add @ComponentScan("package") annotation. In my case the package name is com.shoppingcart.So i wrote the code as @ComponentScan("com.shoppingcart") and it worked for me.

You forgot @Service annotation in your service class.

I believe for @Service you have to add qualifier name like below :

@Service("employeeService") should solve your issue

or after @Service you should add @Qualifier annontion like below :

@Service
@Qualifier("employeeService")

Missing the 'implements' keyword in the impl classes might also be the issue

Guys I found the issue

I just tried by adding the qualifier name in employee service finally it solved my issue.

@Service("employeeService")

public class EmployeeServiceImpl implements EmployeeService{

}

@Service: It tells that particular class is a Service to the client. Service class contains mainly business Logic. If you have more Service classes in a package than provide @Qualifier otherwise it should not require @Qualifier.

Case 1:

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

Case2:

@Service
public class EmployeeServiceImpl implements EmployeeService{
}

both cases are working...

Just add below annotation with qualifier name of service in service Implementation class:

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