(As the saying goes, "speed is the most respected in martial arts, and martial arts in the world can only be broken quickly". This course involves efficient Java programming, which is committed to improving programming efficiency from the two dimensions of "technology" and "tools", helping programmers or future programmers get rid of the "996 curse" and shaping the programming style of "clean code". It mainly includes: chain programming, flow programming, resource closure, Google open source efficient artifact guava, forging efficient ide artifact for yourself, etc., so as to maximize work efficiency, create more value and meet the needs of enterprises.)