單元測試存儲庫spring org.springframework.beans.factory.UnsatisfiedDependencyException

Question

2. 我正在使用Spring Boot和MongoDB創建一個簡單的學校應用程序。 我想測試服務類中定義的方法，但出現以下異常：

    org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name'com.backintime.BackInTimeSpring.Service.TeacherServiceTest': Unsatisfied dependency expressed through field 'teacherService'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.backintime.BackInTimeSpring.Service.TeacherService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} 

3. 我的課程如下：

4. 庫：

    package com.backintime.BackInTimeSpring.Model.Repository; @Component @Repository public interface ITeacherRepository extends MongoRepository<Teacher,String> { @Query("{}") Stream<Teacher> findAllTeachers(); List<Teacher> findByLastNameIgnoreCase(String lastName); List<Teacher> findByFirstNameIgnoreCase(String firstName); } 

5. 服務：

    package com.backintime.BackInTimeSpring.Service; @Component @Service public class TeacherService { @Autowired private ITeacherRepository teacherRepository; public List<Teacher> retrieveAllTeachers(){ return this.teacherRepository.findAllTeachers().sorted(Comparator.comparing(Teacher::getLastName)).collect(Collectors.toList()); } public Teacher retrieveTeachersById(String id) { return this.teacherRepository.findAllTeachers().filter(t -> t.getId().equals(id)).findFirst().get(); } public List<Teacher> retrieveTeachersByLastName(String lastName){ return this.teacherRepository.findByLastNameIgnoreCase(lastName); } public List<Teacher> retrieveTeachersByFirstName(String firstName){ return this.teacherRepository.findByFirstNameIgnoreCase(firstName); } public void saveTeacher(Teacher t){ this.teacherRepository.save(t); } public String greet() { return "Hello World"; } 

   }

6. 單元測試：

    package com.backintime.BackInTimeSpring.Service; @RunWith(SpringRunner.class) @ComponentScan(basePackages = "com.backintime.BackInTimeSpring") public class TeacherServiceTest { @Autowired TeacherService teacherService; @Test public void retrieveAllTeachers() { assertEquals(3, teacherService.retrieveAllTeachers().size()); } 

Answer 1

這是由於您在錯誤的位置使用@ComponentScan而導致的。

通常在主應用程序類或配置類中而不是在定義Bean的地方使用它。

請參考此鏈接： https : //springframework.guru/spring-component-scan/

這里有一個類似的問題，您可以在Main應用程序中使用@ComponentScan看到它們

如何在SpringJunit4TestRunner中將@ComponentScan與測試特定的ContextConfiguration一起使用？