Java 在方面中读取注释属性

如何在方面中读取注释属性值

我希望对所有带有@Transactional（readonly=false）注释的关节点执行我的Around建议

@Around("execution(* com.mycompany.services.*.*(..)) "
+ "&& @annotation(org.springframework.transaction.annotation.Transactional)")
public Object myMethod(ProceedingJoinPoint pjp) throws Throwable {
}

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您必须在代码中执行此操作。比如说

Signature s = pjp.getSugnature();
Method m = s.getDeclaringType().getDeclaredMethod(s.getName(), pjp.getArgs());
Transactional transactional = m.getAnnotation(Transactional.class);
if (transactional != null && !transactional.readOnly()) {
   // code
}

---

但是您真的确定要处理事务吗？

您可以不用手动处理签名，这样（

argNames

用于在没有调试信息的情况下编译时保留参数名称）：

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请参见

您可以这样做：

注释：

@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface Profiled {
    public boolean showArguments();
}

拦截器：

@Aspect
public class ProfilingAspect {

    public static Logger log = LoggerFactory.getLogger("ProfilingAspect");

    @Around("@annotation(profiled)")
    public Object profiled(final ProceedingJoinPoint pjp,
            final Profiled profiled) throws Throwable {
        StopWatch sw = new StopWatch();
        try {
            sw.start();
            return pjp.proceed();
        } finally {
            sw.stop();
            StringBuilder sb = new StringBuilder();
            sb.append("Method ");
            sb.append(pjp.getSignature().getName());
            if (profiled.showArguments()) {
                sb.append(" with arguments ");
                sb.append(Arrays.toString(pjp.getArgs()));
            }
            sb.append(" took ");
            sb.append(sw.getTime());
            sb.append(" millis");
            log.info(sb.toString());
        }
    }
}

---

我希望有一种方法可以使用Around注释来实现这一点。谢谢你的回复。是的。我想在出现OptimisticLockException时重试操作

@Aspect
public class ProfilingAspect {

    public static Logger log = LoggerFactory.getLogger("ProfilingAspect");

    @Around("@annotation(profiled)")
    public Object profiled(final ProceedingJoinPoint pjp,
            final Profiled profiled) throws Throwable {
        StopWatch sw = new StopWatch();
        try {
            sw.start();
            return pjp.proceed();
        } finally {
            sw.stop();
            StringBuilder sb = new StringBuilder();
            sb.append("Method ");
            sb.append(pjp.getSignature().getName());
            if (profiled.showArguments()) {
                sb.append(" with arguments ");
                sb.append(Arrays.toString(pjp.getArgs()));
            }
            sb.append(" took ");
            sb.append(sw.getTime());
            sb.append(" millis");
            log.info(sb.toString());
        }
    }
}