我是aop和aspectj的新手。我正试图围绕元素类型的自定义注解编写一个自定义逻辑 TYPE
. 我还想使用注解下的参数在around方法中编写自定义逻辑。我得到下面提到的错误。我试着阅读多个来源,而且大多数来源都与使用 @annotation
. 我发现同样的道理很难理解。有人能解释一下,为什么用下面的方法 @within
没有明确的例子?
注解(slf4jtrace.java):
package io.ud.project.falcon.logging;
import io.ud.project.falcon.logging.generator.AbstractLogTraceIdGenerator;
import io.ud.project.falcon.logging.generator.DefaultLogTraceIdGenerator;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Slf4jTrace {
String traceKey() default "traceId";
Class<? extends AbstractLogTraceIdGenerator> traceValueGenerator() default DefaultLogTraceIdGenerator.class;
}
方面组件(slf4jtraceaspect.java):
package io.ud.project.falcon.logging;
import lombok.extern.slf4j.Slf4j;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.springframework.stereotype.Component;
@Aspect
@Component
@SuppressWarnings("unused")
@Slf4j
public class Slf4jTraceAspect {
@Pointcut("execution(public * *(..))")
public void publicOperation() {
//Using this pointcut annotation for Around method.
}
@Around(value = "@within(slf4jTrace) && publicOperation()")
public void logTrace(ProceedingJoinPoint joinPoint, Slf4jTrace slf4jTrace) throws Throwable {
//Custom logic that uses slf4jTrace's parameters
joinPoint.proceed();
//Custom logic that uses slf4jTrace's parameters
}
}
注解类(foo.java):
package io.ud.project.falcon.logging;
import io.ud.project.falcon.logging.Slf4jTrace;
@Slf4jTrace(traceKey = "auditID")
public class Foo {
public void doSomething() {
//Something happens here.
}
}
应用程序启动时出错:
, 2021-01-02 22:16:41,340, ERROR [main] o.s.b.SpringApplication.reportFailure(833) | Application run failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'objectMapperConfigurer' defined in springfox.documentation.spring.web.SpringfoxWebMvcConfiguration
: BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.transaction.annotation.ProxyTransactionManagementConfiguration': BeanPostProcessor before instantiation of bean failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.cache.annotation.ProxyCachingConfiguration': Initialization of bean failed; nested exception is java.lang.IllegalArgumentException: error Type referred to is not an annotation type: slf4jTrace
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:497)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:312)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:310)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:205)
at org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:238)
at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:709)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:534)
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:388)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:327)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1234)
at io.ud.project.falcon.FalconApplication.main(FalconServiceApplication.java:65)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
at org.springframework.boot.loader.Launcher.launch(Launcher.java:50)
at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51)
1条答案
按热度按时间zfycwa2u1#
我没有试着运行你的代码,但我一看就立刻注意到两件事:
BeanCreationException
对于内部spring类型,如果aspect切入点太宽,也就是说aspect也被编织到spring类中(即使没有在spring类中执行)。在这种情况下,您希望通过添加以下内容来限制方面范围... && within(my.package..*)
你的切入点。或者,如果您的方面在一个库中,该库可能针对未知的包名运行,那么您可以通过以下方式排除导致问题的spring包或类:!within(org.springframework..*)
或者任何适用于你的包裹名称。请看我的答案。你的
@Around
通知返回void
,即它也将只匹配void
方法,这可能不是你想要的。为了匹配非void方法,通知必须返回void
,通常只是Object
如果要匹配任何返回类型。还要确保返回proceed()
或者任何你想要返回的结果。