面向对象实现计算器功能

public class Counter {
    //加
    public float add(float a,float b){
        return  a+b;
    }
    //减
    public float subtract(float a,float b){
        return  a-b;
    }
    //乘
    public float multiply(float a,float b){
        return  a*b;
    }
    //除
    public float divide(float a,float b){
        return  a/b;
    }

public void Counters(){
        Scanner input=new Scanner(System.in);
        System.out.println("请输入第一个数");
        String one=input.nextLine();
        float a = Float.parseFloat(one);

        //循环 运算
        while (true) {
            System.out.println("请输入运算符");
            String symbol = input.nextLine();
            if (symbol.equals("=")){
                System.out.println("程序结束");
                break;
            }
            if (!(symbol.equals("+")||symbol.equals("-")||symbol.equals("*")||symbol.equals("/")||symbol.equals("="))){
                System.out.println("您输入的运算符不对，请输入+，-，*，/，=");
                continue;
            }
            System.out.println("请输入第二个数");
            String two = input.nextLine();
            //进行数据类型转换
           // float a = Float.parseFloat(one);
            float b = Float.parseFloat(two);

            switch (symbol) {
                case "+":
                    a = this.add(a, b);
                    break;
                case "-":
                    a = this.subtract(a, b);
                    break;
                case "*":
                    a = this.multiply(a, b);
                    break;
                case "/":
                    a = this.divide(a, b);
                    break;
                    }
            System.out.println("运算结果为：" + a);
        }
    }

}