but was actually of type 'com.sun.proxy.$Proxy101' 注入问题

最近在用springboot搭建项目框架时，遇到了如下错误，查询了一番，原来是没有引入spring框架的aop包导致：

问题：

 ERROR o.s.test.context.TestContextManager - Caught exception while allowing TestExecutionListener [org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener@2e3252] to prepare test instance [com.zsm.sb.service.impl.StudentServiceImpTest@d978ab9]
 org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'com.zsm.sb.service.impl.StudentServiceImpTest': Unsatisfied dependency expressed through field 'studentServiceImp'; nested exception is org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'studentServiceImpl' is expected to be of type 'com.zsm.sb.service.impl.StudentServiceImpl' but was actually of type 'com.sun.proxy.$Proxy101'
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:)
 at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:)
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:)
 at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:)
 at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:)
 at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:)
 at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$.runReflectiveCall(SpringJUnit4ClassRunner.java:)
 at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:)
 at org.junit.runners.ParentRunner$.run(ParentRunner.java:)
 at org.junit.runners.ParentRunner$.schedule(ParentRunner.java:)
 at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:)
 at org.junit.runners.ParentRunner.access$(ParentRunner.java:)
 at org.junit.runners.ParentRunner$.evaluate(ParentRunner.java:)
 at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:)
 at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:)
 at org.junit.runners.ParentRunner.run(ParentRunner.java:)
 at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:)
 at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:)
 at org.apache.maven.surefire.junit4.JUnit4Provider.executeWithRerun(JUnit4Provider.java:)
 at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:)
 at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:)
 at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:)
 at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:)
 at org.apache.maven.surefire.booter.ForkedBooter.execute(ForkedBooter.java:)
 at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:)
 Caused by: org.springframework.beans.factory.BeanNotOfRequiredTypeException: Bean named 'studentServiceImpl' is expected to be of type 'com.zsm.sb.service.impl.StudentServiceImpl' but was actually of type 'com.sun.proxy.$Proxy101'
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.checkBeanNotOfRequiredType(DefaultListableBeanFactory.java:)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:)
 at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:)
 ...  common frames omitted

解决方案：

1.添加AOP依赖包

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-aop</artifactId>
</dependency>

2.配置参数：

 spring.aop.proxy-target-class=true 
 <aop:aspectj-autoproxy  proxy-target-class="true"/>

　　spring对AOP有两种实现方式，一种是动态代理，它是通过接口方式实现的，要求所代理的类一定是实现了某一个接口，对一般的类就无法代理，spring默认是这种；一种是通过设置proxy-target-class="true"，则是使用CGLIB实现AOP，CGLIB直接生成二进制码，使得普通类也可以实现AOP。