HeadFirst设计中的MVC展示 功能：管理节拍，维护当前BPM的状态和许多产生MIDI事件的代码，以便让我们听到的节拍，主main函数为DJTestDrive.java-In the design of HeadFirst display MVC Management function: beat, maintenance of current status of BPM and MIDI have many events of the code, so that we can h