Java 项目树更改后的Spring UnsatifiedPendencyException异常

我是Spring的新手，我正在尝试制作一个简单的rest应用程序。当我将所有文件放在一个包中时，应用程序运行良好。因为我改变了我的项目组织，所以我无法构建我的项目。我得到这个错误：

2017-09-30 22:32:48.428  WARN 9428 --- [           main] o.s.w.c.s.GenericWebApplicationContext   : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'application': Unsatisfied dependency expressed through field 'repository'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'socketApp.dal.repository.CustomerRepository' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    2017-09-30 22:32:48.431  INFO 9428 --- [           main] utoConfigurationReportLoggingInitializer : 

    Error starting ApplicationContext. To display the auto-configuration report re-run your application with 'debug' enabled.
    2017-09-30 22:32:48.495 ERROR 9428 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

    ***************************
    APPLICATION FAILED TO START
    ***************************

    Description:

    Field repository in socketApp.main.Application required a bean of type 'socketApp.dal.repository.CustomerRepository' that could not be found.


    Action:

    Consider defining a bean of type 'socketApp.dal.repository.CustomerRepository' in your configuration.

    2017-09-30 22:32:48.496 ERROR 9428 --- [           main] o.s.test.context.TestContextManager      : Caught exception while allowing TestExecutionListener [org.springframework.test.context.web.ServletTestExecutionListener@16267862] to prepare test instance [hello.GreetingControllerTests@47f08b81]

我当前的项目树如下所示

src 
  main 
    java
      app
        dal
          model
            -Customer.java
          repository
            -CustomerRepository.java
        main
          -Aplication.java
        webServices
          -GreetingController.java

这是我的Customer.java文件：

package socketApp.dal.model;

import org.springframework.data.annotation.Id;


public class Customer {

    @Id
    public String id;

    public String firstName;
    public String lastName;

    public Customer() {}

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return String.format(
                "Customer[id=%s, firstName='%s', lastName='%s']",
                id, firstName, lastName);
    }

}

    package socketApp.dal.repository;


import java.util.List;

import org.springframework.data.mongodb.repository.MongoRepository;
import org.springframework.stereotype.Repository;
import socketApp.dal.model.Customer;

@Repository
public interface CustomerRepository extends MongoRepository<Customer, String> {

    public Customer findByFirstName(String firstName);
    public List<Customer> findByLastName(String lastName);


}

My CustomerRepository.java文件：

package socketApp.dal.model;

import org.springframework.data.annotation.Id;


public class Customer {

    @Id
    public String id;

    public String firstName;
    public String lastName;

    public Customer() {}

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return String.format(
                "Customer[id=%s, firstName='%s', lastName='%s']",
                id, firstName, lastName);
    }

}

    package socketApp.dal.repository;


import java.util.List;

import org.springframework.data.mongodb.repository.MongoRepository;
import org.springframework.stereotype.Repository;
import socketApp.dal.model.Customer;

@Repository
public interface CustomerRepository extends MongoRepository<Customer, String> {

    public Customer findByFirstName(String firstName);
    public List<Customer> findByLastName(String lastName);


}

最后是我的GreetingController.java

   package socketApp.webServices;



import socketApp.dal.repository.CustomerRepository;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import socketApp.dal.model.Customer;
import socketApp.dal.model.Greeting;

@RestController
public class GreetingController {

    @Autowired 
    private CustomerRepository repository;


    @RequestMapping("/")
    public List<Customer> getAllCustomers(){
        // fetch all customers
    return repository.findAll();
    }
} 

包socketApp.webServices；
导入socketApp.dal.repository.CustomerRepository；
导入java.util.List；
导入java.util.concurrent.AtomicLong；
导入org.springframework.beans.factory.annotation.Autowired；
导入org.springframework.web.bind.annotation.RequestMapping；
导入org.springframework.web.bind.annotation.RequestParam；
导入org.springframework.web.bind.annotation.RestController；
导入socketApp.dal.model.Customer；
导入socketApp.dal.model.Greeting；
@RestController
公共类迎宾控制器{
@自动连线
私有客户存储库；
@请求映射（“/”）
公共列表getAllCustomers（）{
//招揽所有顾客
返回repository.findAll（）；
}
} 

您必须将

应用程序

类向上移动一个包，以便该类位于其他包之上的包中，或者手动指定

基本包

通过或用于

@springbootplication

启动的组件扫描

看

• 及

---

有关更多详细信息。

默认情况下，

@SpringBootApplication

将只扫描从带注释类的包“降序”的组件包

所以在您的例子中，因为main类位于

socketApp.main

中，而repository位于

socketApp.dal.repository

中，所以不会找到它

您有两个选择：

将

应用程序

移动到软件包

socketApp

package socketApp;    

...

@SpringBootApplication
public class Application implements CommandLineRunner {
...

或添加额外的

@ComponentScan

注释。在您的情况下，它将是：

@SpringBootApplication
@ComponentScan("socketApp")
public class Application implements CommandLineRunner {
...

---

我认为第一种方法更好。

在第二种方法中，您不应该使用

@componentscan

，而是应该使用

@springbootcapplication

的属性，该属性委托给已经存在的@ComponentSan。