狗蛋同学来做四则运算啦！

package 四则运算;
class Calculator{
 private int num1;
 private int num2;
 private char option ;
 public void initCalculator(int num1,int num2,char o) {
 this.num1=num1;
 this.num2=num2;
 if(o=='+'||o=='-'||o=='*'||o=='/') {
  option = o;
 }
 else {
   option = '+';
 }
}

 public void calculate() {
  switch(option) {
  case'+':
   System.out.println("做加法运算，结果是:"+(num1+num2));
  case'-':
   System.out.println("做减法运算，结果是:"+(num1-num2));
  case'*':
   System.out.println("做乘法运算,结果是:"+(num1*num2));
  case'/':
   System.out.println("做除法运算，结果是:"+(num1/num2));
 
  }
 }

}
public class Dome1 {
 public static void main(String[]args) {
  System.out.println("狗蛋同学来做四则运算啦!");
  Calculator c =  new Calculator();
  c.initCalculator(20, 10, 'a');
  c.calculate();
 }
}