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[英]Unsatisfied dependency expressed through constructor parameter 1 with userRepository
[英]Unsatisfied dependency expressed through field 'userRepository'
無法解決測試 Spring Boot 應用程序的問題:
spring.bat init --artifactId=dbproto3 --boot-version=2.1.7.RELEASE --dependencies=jdbc,data-rest,web,thymeleaf,devtools,lombok,configuration-processor,security,data-jpa,data-jdbc,postgresql,actuator --description=dbproto3 --groupId=com.test --java-version=11 --name=dbproto3 --package-name=com.test.dbproto3 --version=0.0.1-SNAPSHOT
它是通過修改 Spring 官方網站的“Accessing data with MySQL”指南制作的測試應用程序。 第一個版本(接近初始:空 springconfig、@Controller 和 @RequestMapping(path="/demo"), ...)效果很好,但我的版本產生了異常
運行它我得到一個例外:
Exception in thread "restartedMain" java.lang.reflect.InvocationTargetException
2 . at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
3 . at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
4 . at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
5 . at java.base/java.lang.reflect.Method.invoke(Method.java:566)
6 . at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
7 . Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mainController': Unsatisfied dependency expressed through field 'userRepository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.test.dbproto3.UserRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
8 . at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596)
9 . at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90)
10 . at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374)
11 . at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1411)
12 . at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592)
13 . at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
14 . at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320)
15 . at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
16 . at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318)
17 . at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
18 . at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:845)
19 . at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877)
20 . at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549)
21 . at org.springframework.context.annotation.AnnotationConfigApplicationContext.<init>(AnnotationConfigApplicationContext.java:88)
22 . at com.test.dbproto3.Dbproto3Application.main(Dbproto3Application.java:18)
23 . ... 5 more
24 . Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.test.dbproto3.UserRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
25 . at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1658)
26 . at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1217)
27 . at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171)
28 . at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593)
29 . ... 19 more
Dbproto3應用程序:
@SpringBootApplication
2 . public class Dbproto3Application {
3 .
4 . public static void main(String[] args) {
5 . SpringApplication.run(Dbproto3Application.class, args);
6 .
7 . ApplicationContext javaConfigContext = new AnnotationConfigApplicationContext(SpringConfig.class);
8 .
9 . MainController mainControllerObj = (MainController) javaConfigContext.getBean("mainController");
10 .
11 . mainControllerObj.addNewUser();
12 . }
13 . }
彈簧配置:
1 . @Configuration
2 . public class SpringConfig {
3 . @Bean("mainController")
4 . public MainController createMainController() {
5 . return new MainController();
6 . }
7 . }
用戶:
1 . @Entity
2 . @Table(name = "userstab")
3 . public class User {
4 . @Id
5 . @GeneratedValue(strategy=GenerationType.AUTO)
6 . private Integer id;
7 .
8 . private String name;
9 .
10 . private String email;
11 .
12 . }
用戶庫:
1 . public interface UserRepository extends CrudRepository<User, Integer> {
2 .
3 . }
主控制器:
3 . public class MainController {
4 .
5 . @Autowired
6 . private UserRepository userRepository;
7 .
8 .
9 . public void addNewUser() {
10 . User n = new User();
11 . n.setName("testuser");
12 . n.setEmail("testemail");
13 . System.out.println("addNewUser()");
14 . userRepository.save(n);
15 . }
16 .
17 . }
應用特性:
server.port = 8082
## default connection pool
spring.datasource.hikari.connectionTimeout=20000
spring.datasource.hikari.maximumPoolSize=5
## PostgreSQL
spring.datasource.url=jdbc:postgresql://localhost:5432/example_db
spring.datasource.username=someuser
spring.datasource.password=123456
spring.jpa.hibernate.ddl-auto=update
我在您共享的代碼中看不到您的存儲庫接口的任何注釋。即使您正在擴展CrudRepository
接口以創建您自己的接口。 Spring boot 需要在啟動期間了解它需要為您的實體提供默認實現。在您的界面上使用注釋@Repository
,例如:
@Repository
public interface UserRepository extends CrudRepository<User, Integer> {
}
此外,您正在以某種奇怪的方式創建控制器 bean,因此您可能正在嘗試一些非常規的東西,這意味着僅在您的主應用程序類中使用@Autowired
對您來說也可能有點牽強。 但我會建議這樣做。 您正在使用AnnotationConfigApplicationContext
為您的控制器創建 bean,但您只提供您為掃描創建的配置類。 也許 UserRepository 的 bean 因為它是由 springboot 創建的,所以在您使用AnnotationConfigApplicationContext
創建的應用程序上下文中不存在。 我認為這是一個獨立的上下文。
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