Spring应用程序上下文有我的bean，但@autowired没有看到它

Question

我正在尝试用注释配置我的Spring Boot应用程序，并在其中使用@Autowired注释。当我检查是否已加载Bean时，它已加载，但使用@Autowired时，它会显示NoSuchBeanDefinitionException

正如您可以进一步看到的那样，我试图检查我的Bean是否真的被加载了，所以当我运行我的应用程序时，我可以在控制台中看到我的Bean的名称。此外，我尝试将“scanBasePackages="com.log.iei.Logistic a"添加到我的@SpringBootApplication注释中，但它什么也没改变。此外，我尝试了字段自动装配

这是我的主要课程：

@SpringBootApplication(scanBasePackages = "com.log.iei.Logistica")
public class LogisticaApplication extends Application {
   public static ConfigurableApplicationContext context;

   @Override
   public void init() throws Exception {
       SpringApplicationBuilder builder = new SpringApplicationBuilder(AppConfig.class);
       context = builder.run(getParameters().getRaw().toArray(new String[0]));
       String[] beanNames = context.getBeanDefinitionNames();
       Arrays.sort(beanNames);
       for (String beanName : beanNames) {
           System.out.println(beanName);
       }

   }

以下是车辆服务等级的一部分：

@Component("vehicleService")
public class VehicleService implements IDao<VehicleEntity> {

    private static VehicleService vehicleService;
    GenericDao<VehicleEntity> dao;

    public VehicleService(){
        dao = new GenericDao<>(VehicleEntity.class);
        System.out.println("==== VehicleService was created ====");
    }

以下是@自动连线部分的一部分：

@Component("cargoPage")
public class CargoPage extends TablePageTemplate {

    @Autowired
    public CargoPage(VehicleService vehicleService){
        getAboveTableLine().getChildren().addAll(getAboveTableLineSetup());

        setTable(getTable(), vehicleService.findAll(), VehicleEntity.getTableMapping());

这里有一个错误：

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.log.iei.Logistica.data.controllers.Services.VehicleService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1654)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1213)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1167)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)
    ... 24 more

UPD：可能问题在于VehicleService实现了通用接口。

Answer 1

您应该检查您的文件是否在基本包中。例如，如果您有：

com.log
       .service
               VehicleService.java
               CargoPage.java
       LogisticaAplication.java

因此，在您的Logistic aApplication.java中，您应该将底座添加为以下内容：

@SpringBootApplication(scanBasePackages = "com.log")
public class LogisticaApplication extends Application {
   public static ConfigurableApplicationContext context;

   @Override
   public void init() throws Exception {
       SpringApplicationBuilder builder = new SpringApplicationBuilder(AppConfig.class);
       context = builder.run(getParameters().getRaw().toArray(new String[0]));
       String[] beanNames = context.getBeanDefinitionNames();
       Arrays.sort(beanNames);
       for (String beanName : beanNames) {
           System.out.println(beanName);
       }

   }

Answer 2

首先，您必须将基本包设置为：

@SpringBootApplication(scanBasePackages = "com.log")

您正确地映射了所有内容，但是，用于Autowire bean的构造函数不应该调用任何其他逻辑。如果您需要在bean初始化之后立即执行某些操作，请使用PostConstruct。

您的代码是这样的：

@Service
public class CargoPage extends TablePageTemplate {

    private VehicleService vehicleService;

    @Autowired
    public CargoPage(VehicleService vehicleService) {
        this.vehicleService = vehicleService;
    }

    @PostConstruct
    public void init() {
        getAboveTableLine().getChildren().addAll(getAboveTableLineSetup());
        setTable(getTable(), vehicleService.findAll(), VehicleEntity.getTableMapping());
    }
}