执行方法想知道这个方法的耗时，优雅方式一

1 ，新建一个处理统计耗时的业务类
public class TimeWatcherObject{
    private final Logger log;

    public static TimeWatcher build(Logger logger) {
        return new TimeWatcher(logger);
    }

    private TimeWatcher(Logger log) {
        this.log = log;
    }

    public <T> void aroundVoid(String label, Supplier<T> action) {
        LocalDateTime start = LocalDateTime.now();
        String endTerm = "结束";

        try {
            this.log.info("【{}】开始", label);
            action.get();
        } catch (Throwable var9) {
            endTerm = "异常结束";
            this.log.error(var9.getMessage(), var9);
            throw var9;
        } finally {
            this.log.info("【{}】{}。耗时 = {}", new Object[]{label, endTerm, Duration.between(start, LocalDateTime.now())});
        }
    }

2，然后在你的业务代码中调用：

TimeWatcherObject.build(log)
       .aroundVoid(label, () -> {
           //XX是你要统计耗时的执行方法
          XX();
          return Optional.empty();
       })