A Supplement to the Journey to the West is a Chinese novel from around 1640 that was written as a type of addendum to the great classic novel Journey to the West. Journey to the West is set during the Tang dynasty (618 - 907), since it involves a character, Xuanzang that lived during that period. In A Supplement to the Journey to the West, one of the characters, Sun Wukong aka Monkey
leaps through and travels hundreds of years forward in time to the Song Dynasty,
which officially lasted from 960 until 1279, and later returns to the Tang dynasty (618 to 907 AD).
In the West (i.e. Europe, not the "West" from the novel's title), the concept of time travel was popularised by H. G. Wells' story The Time Machine, published in 1895, i.e. three and a half centuries after A Supplement to the Journey to the West. The Wikipedia article on time travel mentions older examples from other literatures, e.g. from the Mahabharata (India) and from 8th-century Japanese literature. Is A Supplement to the Journey to the West the oldest Chinese example? If not, what is the oldest one?