说明：  通过JAVA设计 GUI 界面的计算器程序，用户可以通过鼠标依次输入参加计算的数值，进行加、减、乘、除等混合运算,这些完成标准计算器的基础操作。当选择科学计算器后，可以实现sin 、 cos 、 tan 、 ln、x^y、x^2、x^3、pi、n!、mod和十六进制除这个以外还可以删除输入，清空结果，求1除X，X百分比，十进制是，八进制，二进制的相互转换
(Through JAVA calculator program designed GUI interface, users can turn the mouse input to participate in the calculation of the values to add, subtract, multiply, in addition to mixed operations, the basis for these operations to complete the standard calculator. When you choose the scientific calculator, you can achieve the sin, cos, tan, ln, x ^ y, x ^ 2, x ^ 3, pi, n!, Mod, and hexadecimal In addition to the other can also delete input, empty a result, seeking an addition to X, X percentage, decimal is, octal, binary mutual conversion)