包装org.example; @方面 @order（value = 2） @成分 公共课程SayAspect { @declareparents（value =“ org.example ..*+”，defaultimpl = defaultgoodbye.class） 私人告别

Question

您可能正在使用Intellij Idea和Mean

( expected

，而不是主题行中所述。

Answer 1

这是Idea extactJ和春季AOP支持的故障。如果您只是忽略它，那么方面仍然可以正常工作。我尝试过，它效果很好：) expected

package org.example;

public interface GoodBye {
  String getGoodBye();
}

package org.example;

public class DefaultGoodBye implements GoodBye {
  @Override
  public String getGoodBye() {
    return "Farewell";
  }
}

package org.example;

import org.springframework.stereotype.Component;

@Component
public class MyComponent {
  public void sayHello() {
    System.out.println("Hello");
  }

  public void sayGoodBye() {
    System.out.println("Good bye");
  }
}

package org.example;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.aspectj.lang.annotation.DeclareParents;
import org.springframework.core.annotation.Order;
import org.springframework.stereotype.Component;

import java.util.Arrays;

@Aspect
@Order(value = 2)
@Component
public class SayAspect {
  @DeclareParents(value = "org.example..*", defaultImpl = DefaultGoodBye.class)
  private GoodBye goodBye;
  private int count = 0;

  @Before("execution(* org.example.MyComponent.sayHello())")
  public void beforeHello(JoinPoint joinPoint) {
    System.out.println("Before Hello");
    System.out.println(Arrays.toString(joinPoint.getTarget().getClass().getInterfaces()));
    System.out.println(Arrays.toString(joinPoint.getThis().getClass().getInterfaces()));
  }
}

Console Log说：

package org.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

@SpringBootApplication
public class DemoApplication {
  public static void main(String[] args) {
    try (ConfigurableApplicationContext appContext = SpringApplication.run(DemoApplication.class, args)) {
      doStuff(appContext);
    }
  }

  private static void doStuff(ConfigurableApplicationContext appContext) {
    MyComponent myComponent = appContext.getBean(MyComponent.class);
    myComponent.sayHello();
    myComponent.sayGoodBye();
    System.out.println(((GoodBye) myComponent).getGoodBye());
  }
}

你可以看到，

the以前的建议开始，

组件代理实现

Before Hello
[]
[interface org.example.GoodBye, interface org.springframework.aop.SpringProxy, interface org.springframework.aop.framework.Advised, interface org.springframework.cglib.proxy.Factory]
Hello
Good bye
Farewell

接口，

可以将代理组件施加到

GoodBye

中，并调用其

GoodBye

方法会产生默认实现的预期结果。