It lets you track message at certain points in their life cycle by invoking custom code from user exits while the message is passing through the message flow.

它允许您在消息通过消息流传递时调用用户出口中的自定义代码，从而在消息生命周期中的某个点跟踪消息。

youdao

First, it would complicate your code because you would have to manage a pool and track the life cycle of the XHR instances.

首先，它将使代码变得复杂，因为您将不得不进行池的管理，也不得不跟踪xhr实例的生命周期。

youdao

Track claims throughout the claim life cycle.

在整个索赔生命周期中跟踪索赔。

youdao

Cyclists proceed along a smooth cycle track, a paved path separated from cars and pedestrians by curbs.

FORBES: What's It Like To Get Around By Bike In Copenhagen? Take A Virtual Tour

Then in 2007, an extra site was found after an observant cyclist found it growing beside a cycle track in Llanelli.

BBC: Deptford Pink's Flintshire site sees 14-fold increase

For example, one way to track the reproductive cycle in a female is to follow the waxing and waning of sex hormones.

ECONOMIST: Endangered species