java - Spring MVC错误通过字段表达的依赖关系不满足

Question

需要一些帮助来解决此错误，不久前它工作正常，但当我添加存储库部分时问题开始了。我已经在堆栈上尝试了建议的解决方案，但我的应用程序仍然无法运行。

我正在尝试使用 Spring Boot、Spring MVC 和 JSP 作为 UI 创建一个简单的 Web 应用程序。虽然我过去创建过 spring mvc Web 应用程序，但这将是我第一次使用 spring boot。如果您能指出问题，我将不胜感激。谢谢

Controller 类

@Controller
public class ChartsController {

    private static final Logger logger = Logger.getLogger(ChartsController.class);

    @Autowired
    ChartRepo cityDao;


    @RequestMapping("/")
    public String home() {

        return "home";

    }


    @RequestMapping("/report")
    public String reportPage() {

        return "Report";
    }

    @RequestMapping("/dbReport")
    public ModelAndView reportCity() {

        ModelAndView model = new ModelAndView("dbReport");

        FusionCharts fc= retrieveNameAndPopulation();

        model.addObject("fusionCharts", fc);

        return model;
    }
}

存储库类

import org.charts.model.City
import org.springframework.data.jpa.repository.JpaRepository;


public interface ChartRepo extends JpaRepository<City, Long>{

}

配置类

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import org.springframework.web.servlet.config.annotation.DefaultServletHandlerConfigurer;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;

@Configuration
@EnableAutoConfiguration
@EnableWebMvc
@ComponentScan("org.charts")
@EntityScan(basePackages={"org.charts.model"})
@EnableJpaRepositories(basePackages={"org.charts.repositories"})
@EnableTransactionManagement
public class ChartConfig extends WebMvcConfigurerAdapter{

    @Bean
    public InternalResourceViewResolver setupViewResolver()  {
        InternalResourceViewResolver resolver =  new InternalResourceViewResolver();
        resolver.setPrefix ("/WEB-INF/jsp/");
        resolver.setSuffix (".jsp");
        resolver.setViewClass (JstlView.class);
        return resolver;
    }

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }
}

主类

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.ComponentScan;

@SpringBootApplication
public class Charts {

    public static void main(String [] args) {

        SpringApplication.run(Charts.class, args);
    }

}

错误信息

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'chartsController': Unsatisfied dependency expressed through field 'cityDao': No qualifying bean of type [org.charts.repository.ChartRepo] found for dependency [org.charts.repository.ChartRepo]: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.charts.repository.ChartRepo] found for dependency [org.charts.repository.ChartRepo]: 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$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:569) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:776) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:369) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:313) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1185) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1174) [spring-boot-1.4.0.RELEASE.jar:1.4.0.RELEASE]
    at org.charts.Charts.main(Charts.java:13) [classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_121]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_121]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_121]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_121]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-1.4.0.RELEASE.jar:1.4.0.RELEASE]
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.charts.repository.ChartRepo] found for dependency [org.charts.repository.ChartRepo]: 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.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1406) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1057) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1019) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:566) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    ... 24 common frames omitted

Answer 1

您正在扫描org.charts.repositories包

@EnableJpaRepositories(basePackages={"org.charts.repositories"})

而您的 ChartRepo 存储库位于 org.charts.repository 包中。因此，Spring 不能将存储库视为 bean，也不会 Autowiring 它。