Emperor Jianming, of course, wasn't actually named Jianming, but rather that was his honorific title.
The current emperor's honorific title, Jianming, means to establish and to be wise.
Since ancient times, it has been forbidden to address emperors by their birth names, so instead, they were given titles. An emperor's titles generally include his honorific title, reign title, temple name, and posthumous name.
1. Temple name: a title given after an emperor's death when his spirit is worshiped in the imperial ancestral temple, such as Taizu, Gaozu, Shizu, Shengzu, Taizong, Gaozong, Xianzong, and Suzong, among others.
2. Honorific title: while the emperor is alive, his ministers begin to request this, which usually involves bestowing good words upon the emperor, and the title tends to get longer and longer.