问题

Error creating bean with name 'bookController': 
Unsatisfied dependency expressed through field 'bookService'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException:
No qualifying bean of type 'com.kai.service.BookService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: 
{@org.springframework.beans.factory.annotation.Autowired(required=true), @org.springframework.beans.factory.annotation.Qualifier(value=bookServiceImp)}

问题大概就是bookController类下找不到bookService对象（通过注解注入的value为bookServiceImp实例化的对象）

首先看下我的bookController类

@Controller
@RequestMapping("/book")
public class BookController {

    //自动装配bean根据id
    @Autowired
    @Qualifier("bookServiceImp")
    private BookService bookService;

    @RequestMapping("/allBook")
    public String list(Model model){

        List<Books> books = bookService.queryAllBook();
        model.addAttribute("books",books);
        return "allBook";
    }
}

spring-service.xml的bookServiceImp的bean注入

    <bean id="bookServiceImp" class="com.kai.service.BookServiceImp">
        <property name="mapper" ref="bookMapper"/>
    </bean>

从这看注入没问题。然后去试一下是不是底层出错

    @Test
    public void test(){
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        BookServiceImp serviceImp = (BookServiceImp) context.getBean("bookServiceImp");
        List<Books> books = serviceImp.queryAllBook();
        for (Books book : books) {
            System.out.println(book);
        }
    }

能查找到数据，底层没问题但是为什么bean不行呢。。。

肯定是spring配置出了问题才找不到bean

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd ">

    <import resource="classpath:spring-dao.xml"/>
    <import resource="classpath:spring-service.xml"/>
    <import resource="classpath:spring-mvc.xml"/>
</beans>

三个都导入了呀。。。

原因：

先看下web.xml 圈起来的位置是spring-mvc.xml
DispatcherServlet仅仅导入了spring-mvc的配置没有导入service和dao的配置
无法进行调用生成！

解决办法

将上图位置中的spring-mvc.xml修改成applicationContext.xml即可