1、 当程序需接收用户通过键盘输入的指令或数据，如计算表达式时，可利用Scanner类便捷地实现输入获取与处理。 2、 使用Scanner类读取用户输入时，程序会在控制台持续等待，直至用户按下回车键确认输入。此时，输入的内容将被传递给Scanner对象。若需获取该 ...

In a previous Java 101 tutorial, you learned how to better organize your code by declaring reference types (also known as classes and interfaces) as members of other reference types and blocks. I also ...