Question

我有一个可用于注释的方面：

@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface DumpToFile {

}

连接点：

@Aspect
@Component
public class DumpToFileAspect {

  @Around("@annotation(DumpToFile)")
  public Object logExecutionTime(ProceedingJoinPoint joinPoint) throws Throwable {

    ...
    // I likte to read out a parameter from the annotation...
    Object proceed = joinPoint.proceed();

    ...

    return proceed;
  }
}

我可以在使用@DumpToFile的方法上成功使用方面。但是，我想将参数传递给注释，并在我的方面中获取它的值。
例如。 @DumpToFile(fileName="mydump")。有人可以告诉我该怎么做吗？

Answer 1

将您的@Around更改为：

@Aspect
@Component
public class DumpToFileAspect {

  @Around("@annotation(dumpToFileAspect)")
  public Object logExecutionTime(ProceedingJoinPoint joinPoint, DumpToFile dumpToFileAspect) throws Throwable {

    ...
    // I likte to read out a parameter from the annotation...
    String fileName = dumpToFileAspect.getFileName();
    Object proceed = joinPoint.proceed();

    ...

    return proceed;
  }
}

Answer 2

您应该能够将注释接口传递给拦截器方法。我还没试过自己。

Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface DumpToFile {

      String fileName() default "default value";

}

在DumpToFileAspect中-

@Aspect
@Component
public class DumpToFileAspect {

  @Around("@annotation(dtf)")
  public Object logExecutionTime(ProceedingJoinPoint joinPoint, DumpToFile dtf) throws Throwable {

    ...
    // I likte to read out a parameter from the annotation...

    System.out.println(dtf.fileName); // will print "fileName"

    Object proceed = joinPoint.proceed();

    ...

    return proceed;
  }
}

Answer 3

您可以使用此：

 @Around("@annotation(dumpFile)")
  public Object logExecutionTime(ProceedingJoinPoint joinPoint,DumpToFile dumpFile)

@annotation内部必须是DumpToFile参数名称。

有关详细信息，请参见documentation

具有方面参数的注释

3 个答案: