我想在springboot项目中创建一个AspectJ组件，该组件在存在@Loggable注释，方法或类或两者都存在的情况下打印日志消息（将考虑方法）。
可记录注释：
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.TYPE, ElementType.METHOD })
public @interface Loggable {
boolean duration() default false;
}
Aspectj类：
@Aspect
@Component
public class LogInterceptorAspect {
@Pointcut("execution(public * ((@Loggable *)+).*(..)) && within(@Loggable *)")
public boolean loggableDefinition(Loggable loggable) {
return loggable.duration();
}
@Around("loggableDefinition(withDuration)")
public void log(ProceedingJoinPoint joinPoint, boolean withDuration) throws Throwable {
getLogger(joinPoint).info("start {}", joinPoint.getSignature().getName());
StopWatch sw = new StopWatch();
Object returnVal = null;
try {
sw.start();
returnVal = joinPoint.proceed();
} finally {
sw.stop();
}
getLogger(joinPoint).info("return value: {}, duration: {}", returnVal, sw.getTotalTimeMillis()));
}
private Logger getLogger(JoinPoint joinPoint) {
return LoggerFactory.getLogger(joinPoint.getSignature().getDeclaringType());
}
}
有了上面的代码，我得到
java.lang.IllegalArgumentException：在切入点:: 0形式上未绑定的错误
怎么了？
最佳答案
基本上，形式参数在PointCut上是未绑定的。
这是一个基于本文详细介绍的方法的替代工作示例：@AspectJ Class level Annotation Advice with Annotation as method argument
我出于以下几个原因略微修改了您的方法，以避免出现此问题：
简化了最初的PointCut并赋予了其单一责任
给它起一个描述性的名称，表明其用途
通过消除对Loggable的依赖关系使其更可重用
使它在实施过程中与大多数可用的示例文档保持紧密联系
将“建议”分为两种更简单的方法，每种方法都有一个容易理解的责任
通过删除花哨的运算符来简化表达式
将注解直接注入到使用该注解的Advice中，而不是尝试从PointCut中传递，这感觉像是不必要的复杂性
使它在实施过程中与大多数可用的示例文档保持紧密联系
添加了单元测试的开始以验证预期的行为，以便可以负责任地对PointCut和Advice表达式进行更改（您应该完成它）
在使用PointCut / Advice表达式时，我通常会尝试使用最简单，最清晰的解决方案，并对它们进行彻底的单元测试，以确保达到我期望的行为。下一个查看您的代码的人将不胜感激。
希望这可以帮助。
package com.spring.aspects;
import static org.junit.Assert.assertEquals;
import org.aspectj.lang.JoinPoint;
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.junit.Test;
import org.junit.runner.RunWith;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.EnableAspectJAutoProxy;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.util.StopWatch;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@RunWith(SpringRunner.class)
@ContextConfiguration(classes = AspectInjectAnnotationTest.TestContext.class)
public class AspectInjectAnnotationTest {
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.TYPE, ElementType.METHOD })
public @interface Loggable {
boolean duration() default false;
}
@Aspect
public static class LogInterceptorAspect {
@Pointcut("execution(public * *(..))")
public void anyPublicMethod() {
}
@Around("anyPublicMethod() && @annotation(loggable)")
public Object aroundLoggableMethods(ProceedingJoinPoint joinPoint, Loggable loggable) throws Throwable {
return log(joinPoint, loggable);
}
@Around("(anyPublicMethod() && !@annotation(AspectInjectAnnotationTest.Loggable)) && @within(loggable)")
public Object aroundPublicMethodsOnLoggableClasses(ProceedingJoinPoint joinPoint, Loggable loggable)
throws Throwable {
return log(joinPoint, loggable);
}
public Object log(ProceedingJoinPoint joinPoint, Loggable loggable) throws Throwable {
getLogger(joinPoint).info("start [{}], duration [{}]", joinPoint.getSignature().getName(),
loggable.duration());
StopWatch sw = new StopWatch();
Object returnVal = null;
try {
sw.start();
returnVal = joinPoint.proceed();
} finally {
sw.stop();
}
getLogger(joinPoint).info("return value: [{}], duration: [{}]", returnVal, sw.getTotalTimeMillis());
return returnVal;
}
private Logger getLogger(JoinPoint joinPoint) {
return LoggerFactory.getLogger(joinPoint.getSignature().getDeclaringType());
}
}
// class level annotation - should only proxy public methods
@Loggable(duration = true)
public static class Service1 {
// public - should be proxied
public String testS1M1(String test) {
return testProtectedM(test);
}
// public - should be proxied
public String testS1M2(String test) {
return testProtectedM(test);
}
// protected - should not be proxied
protected String testProtectedM(String test) {
return testPrivateM(test);
}
// private - should not be proxied
private String testPrivateM(String test) {
return test;
}
}
// no annotation - class uses method level
public static class Service2 {
@Loggable
public String testS2M1(String test) {
return protectedMethod(test);
}
// no annotation - should not be proxied
public String testS2M2(String test) {
return protectedMethod(test);
}
// protected - should not be proxied
protected String protectedMethod(String test) {
return testPrivate(test);
}
// private - should not be proxied
private String testPrivate(String test) {
return test;
}
}
// annotation - class and method level - make sure only call once
@Loggable
public static class Service3 {
@Loggable
public String testS3M1(String test) {
return test;
}
}
// context configuration for the test class
@Configuration
@EnableAspectJAutoProxy
public static class TestContext {
// configure the aspect
@Bean
public LogInterceptorAspect loggingAspect() {
return new LogInterceptorAspect();
}
// configure a proxied beans
@Bean
public Service1 service1() {
return new Service1();
}
// configure a proxied bean
@Bean
public Service2 service2() {
return new Service2();
}
// configure a proxied bean
@Bean
public Service3 service3() {
return new Service3();
}
}
@Autowired
private Service1 service1;
@Autowired
private Service2 service2;
@Autowired
private Service3 service3;
@Test
public void aspectShouldLogAsExpected() {
// observe the output in the log, but craft this into specific
// unit tests to assert the behavior you are expecting.
assertEquals("service-1-method-1", service1.testS1M1("service-1-method-1")); // expect logging
assertEquals("service-1-method-2", service1.testS1M2("service-1-method-2")); // expect logging
assertEquals("service-2-method-1", service2.testS2M1("service-2-method-1")); // expect logging
assertEquals("service-2-method-2", service2.testS2M2("service-2-method-2")); // expect no logging
assertEquals("service-3-method-1", service3.testS3M1("service-3-method-1")); // expect logging once
}
}