我有处理用户实体的用户服务，并且在使用用户服务之前在用户 Controller 类中使用@Autowired。所以，我得到了错误:
Unsatisfied 'required' dependency of type [class com.yes.service.UserService]. Expected at least 1 matching bean
这里是代码:
用户服务
package com.yes.service;
import java.util.List;
import java.util.UUID;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import com.yes.domain.User;
import com.yes.repository.RoleRepository;
import com.yes.repository.UserRepository;
@Service
public class UserService {
@Autowired
private UserRepository userRepository;
@Autowired
private RoleRepository roleRepository;
public User create(User user) {
user.setId(UUID.randomUUID().toString());
user.getRole().setId(UUID.randomUUID().toString());
// We must save both separately since there is no cascading feature
// in Spring Data MongoDB (for now)
roleRepository.save(user.getRole());
return userRepository.save(user);
}
public User read(User user) {
return user;
}
public List<User> readAll() {
return userRepository.findAll();
}
public User update(User user) {
User existingUser = userRepository.findByUsername(user.getUserName());
if (existingUser == null) {
return null;
}
existingUser.setFirstName(user.getFirstName());
existingUser.setLastName(user.getLastName());
existingUser.getRole().setRole(user.getRole().getRole());
// We must save both separately since there is no cascading feature
// in Spring Data MongoDB (for now)
roleRepository.save(existingUser.getRole());
return userRepository.save(existingUser);
}
public Boolean delete(User user) {
User existingUser = userRepository.findByUsername(user.getUserName());
if (existingUser == null) {
return false;
}
// We must delete both separately since there is no cascading feature
// in Spring Data MongoDB (for now)
roleRepository.delete(existingUser.getRole());
userRepository.delete(existingUser);
return true;
}
}
userController(我在其中使用 userService，问题是)
@Controller
@RequestMapping("/users")
public class UserController {
@Autowired
private UserService service;
@RequestMapping
public String getUsersPage() {
return "users";
}
@RequestMapping(value="/records")
public @ResponseBody UserListDto getUsers() {
UserListDto userListDto = new UserListDto();
userListDto.setUsers(service.readAll());
return userListDto;
}
@RequestMapping(value="/get")
public @ResponseBody User get(@RequestBody User user) {
return service.read(user);
}
@RequestMapping(value="/create", method=RequestMethod.POST)
public @ResponseBody User create(
@RequestParam String username,
@RequestParam String password,
@RequestParam String firstName,
@RequestParam String lastName,
@RequestParam Integer role) {
Role newRole = new Role();
newRole.setRole(role);
User newUser = new User();
newUser.setUserName(username);
newUser.setPassword(password);
newUser.setFirstName(firstName);
newUser.setLastName(lastName);
newUser.setRole(newRole);
return service.create(newUser);
}
@RequestMapping(value="/update", method=RequestMethod.POST)
public @ResponseBody User update(
@RequestParam String username,
@RequestParam String firstName,
@RequestParam String lastName,
@RequestParam Integer role) {
Role existingRole = new Role();
existingRole.setRole(role);
User existingUser = new User();
existingUser.setUserName(username);
existingUser.setFirstName(firstName);
existingUser.setLastName(lastName);
existingUser.setRole(existingRole);
return service.update(existingUser);
}
@RequestMapping(value="/delete", method=RequestMethod.POST)
public @ResponseBody Boolean delete(
@RequestParam String username) {
User existingUser = new User();
existingUser.setUserName(username);
return service.delete(existingUser);
}
}
spring-data.xml
<?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:c="http://www.springframework.org/schema/c" xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mongo="http://www.springframework.org/schema/data/mongo"
xmlns:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.1.xsd
http://www.springframework.org/schema/data/mongo
http://www.springframework.org/schema/data/mongo/spring-mongo-1.0.xsd
http://www.springframework.org/schema/util
http://www.springframework.org/schema/util/spring-util-3.1.xsd">
<context:property-placeholder
properties-ref="deployProperties" />
<!-- MongoDB host -->
<mongo:mongo host="${mongo.host.name}" port="${mongo.host.port}" />
<!-- Template for performing MongoDB operations -->
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate"
c:mongo-ref="mongo" c:databaseName="${mongo.db.name}" />
<!-- Activate Spring Data MongoDB repository support -->
<mongo:repositories base-package="com.yes.repository" mongo-template-ref="mongoTemplate"/>
<!-- Service for initializing MongoDB with sample data using MongoTemplate -->
<bean id="initMongoService" class="com.yes.service.InitMongoService" init-method="init"/>
</beans>
servlet-context.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
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.xsd">
<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->
<!-- Enables the Spring MVC @Controller programming model -->
<annotation-driven />
<context:component-scan base-package="com.yes.controller"/>
<!-- Handles HTTP GET requests for /resources/** by efficiently serving up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />
<!-- Resolves views selected for rendering by @Controllers to .jsp resources in the /WEB-INF/views directory -->
<beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean>
applicationContext.xml
<?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:p="http://www.springframework.org/schema/p" 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">
<context:property-placeholder
properties-ref="deployProperties" />
<!-- Activates various annotations to be detected in bean classes -->
<context:annotation-config />
<!-- Scans the classpath for annotated components that will be auto-registered
as Spring beans. For example @Controller and @Service. Make sure to set the
correct base-package -->
<context:component-scan base-package="com.yes.domain"/>
<context:component-scan base-package="com.yes.dto"/>
<context:component-scan base-package="com.yes.service"/>
<!-- Configures the annotation-driven Spring MVC Controller programming
model. Note that, with Spring 3.0, this tag works in Servlet MVC only! -->
<mvc:annotation-driven />
<mvc:resources mapping="/resources/**" location="/resources/" />
<!-- Imports datasource configuration -->
<import resource="spring-data.xml" />
<bean id="deployProperties"
class="org.springframework.beans.factory.config.PropertiesFactoryBean"
p:location="/WEB-INF/spring/spring.properties" />
错误堆栈:
ERROR: org.springframework.web.servlet.DispatcherServlet - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userController': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private com.yes.service.UserService com.yes.controller.UserController.service; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No matching bean of type [com.yes.service.UserService] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:287)
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/applicationContext.xml</param-value>
</context-param>
<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Processes application requests -->
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>appServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
编辑:问题是在修复 Sotirios Delimanolis 答案和评论中写入的错误之后提出的。
是什么问题导致了这个错误？
答案:问题是 Sotirios Delimanolis 答案中所描述的。他的答案的评论中描述了确切的解决方案
谢谢
最佳答案
您的应用程序上下文和 servlet 上下文是对相同包的组件扫描。
您的应用程序上下文
<context:component-scan base-package="com.yes" />
与 servlet 上下文中的所有内容相比
<context:component-scan base-package="com.yes.service"/>
<context:component-scan base-package="com.yes.controller"/>
<context:component-scan base-package="com.yes.domain"/>
<context:component-scan base-package="com.yes.repository"/>
<context:component-scan base-package="com.yes.dto"/>
所以一些bean将被覆盖。你不想要这个。您的 servlet 上下文应该扫描 @Controller bean。您的应用程序上下文应该扫描其他所有内容，但不要让您的应用程序上下文扫描您的子(导入)数据上下文已扫描的内容。修复您的包声明，使所有这些声明都是不相交的。
关于java - spring mvc @Autowired错误不满足 'required'类型依赖，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/18473236/