04年接触了一段时间的java，期间写了比较多小程序段，写得最完整的就是这个java小画板程序，涉及到鼠标事件、画图函数、文件流、文件的打开与保存等内容。 -a small application, in a game in which users randomly picked four cards using the arithmetic method of connecting them, making the results mean 24