Pass method argument in Aspect of custom annotation

Question

I\'m trying to use something similar to org.springframework.cache.annotation.Cacheable :

Custom annotation:

@Target(ElementType.METHOD)
             


        

Answer 1

Your annotation can be used with methods with more than 1 parameter, but that doesn't mean you can't use the arguments array. Here's a sollution:

First we have to find the index of the "id" parameter. This you can do like so:

 private Integer getParameterIdx(ProceedingJoinPoint joinPoint, String paramName) {
    MethodSignature methodSignature = (MethodSignature) joinPoint.getSignature();

    String[] parameterNames = methodSignature.getParameterNames();
    for (int i = 0; i < parameterNames.length; i++) {
        String parameterName = parameterNames[i];
        if (paramName.equals(parameterName)) {
            return i;
        }
    }
    return -1;
}

where "paramName" = your "id" param

Next you can get the actual id value from the arguments like so:

 Integer parameterIdx = getParameterIdx(joinPoint, "id");
 Long id = joinPoint.getArgs()[parameterIdx];

Of course this assumes that you always name that parameter "id". One fix there could be to allow to specify the parameter name on the annotation, something like

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface CheckEntity {
    String message() default "Check entity msg";
    String key() default "";
    String paramName() default "id";
}