验证service出现错误

Question

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'com.imooc.o2o.service.AreaServiceTest': Unsatisfied dependency expressed through field 'areaService'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.imooc.o2o.service.AreaService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:588)

at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264)

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:386)

at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118)

at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)

at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287)

at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:289)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)

at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)

at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)

at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)

at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)

at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)

at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)

at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)

at org.junit.runners.ParentRunner.run(ParentRunner.java:363)

at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)

at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)

at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)

at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.imooc.o2o.service.AreaService' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}

at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1486)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1104)

at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066)

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585)

... 28 more

Answer 1

翔仔 2017-10-17 17:24:05

同学，从错误来看非常明确No qualifying bean of type 'com.imooc.o2o.service.AreaService' available: expected at least 1 bean which qualifies as autowire candidate. 

就是您的AreaServiceImpl即实现类没有加@Service标签，加上就能解决了 因为它让spring容器注入的时候没找到接口的实现类

• 提问者 慕沐9176134 #1

  老师，我加了呀
  import java.util.List;
  
  import org.springframework.beans.factory.annotation.Autowired;
  import org.springframework.stereotype.Service;
  
  import com.imooc.o2o.dao.AreaDao;
  import com.imooc.o2o.entity.Area;
  import com.imooc.o2o.service.AreaService;
  
  @Service
  public class AreaServiceImpl implements AreaService {
  	@Autowired
  	private AreaDao areaDao;
  	@Override
  	public List<Area> getAreaList() { 
  		return areaDao.queryArea();
  	}
  
  }

• 提问者 慕沐9176134 #2

  在service实现类impl类上加了@service
  @Service
  public class AreaServiceImpl implements AreaService {
  
  }

• 翔仔 回复 提问者 慕沐9176134 #3

  同学，请问在spring-service.xml也就是spring的配置文件中加入这句话了吗    <!-- 扫描service包下所有使用注解的类型 -->
      <context:component-scan base-package="com.imooc.o2o.service" /> 就是告诉spring要去这下面去扫它的实现类出来

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