We use the future perfect tense to talk about an action that will be completed at a given time in the future.

我们用将来完成时态来形容一个在未来特定的一个时间已经完成的动作。

youdao

There are three kinds of shapes of the tenses in the Utopia Novels of the later Qing Dynasty: the future past tense, the future perfect tense and the future continuous tense.

晚清的乌托邦小说在时间构形上通常表现为“将来过去时”、“将来完成时”和“将来进行时”等三种不同面相。

youdao

'I have eaten' is the present perfect tense of the verb 'to eat', 'I had eaten' is the past perfect and 'I will have eaten' is the future perfect.

I have eaten是动词eat的现在完成时；I had eaten是过去完成时；I will have eaten是将来完成时。

《牛津词典》