javaBean简易计算器只能运行加法，哪里出错了？

java类代码块

package c;
public class Calculate {
    double x;
    double y;
    double result;
    String operator="+";
    public void setX(double a) {
        x=a;
    }
    public double getX() {
        return x;
    }
    public void setY(double b) {
        y=b;
    }
    public double getY() {
        return y;
    }
    public void setOperator(String s) {
        operator=s.trim();
    }
    public String getOperator() {
        return operator;
    }
    public void setResult(double r){
        result=r;
    }
    public double getResult() {
        if(operator.equals("+"))
            result=x+y;
        else if(operator.equals("-"))
            result=x-y;
        else if(operator.equals("*"))
            result=x*y;
        else if(operator.equals("/") && y!=0)
            result=x/y;
        return result;
    }
}

jsp代码块

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ page import="c.*" %>
class="c.Calculate" scope="session">


name="count"/>
method=post name=form>
    <input type="text" name="x" 
    value="">
    <select name="count">
        <option value="+">+
        <option value="-">-
        <option value="*">*
        <option value="/">/
    select>
    <input type="text" name="y" 
    value="">
    =name="count"/>
    
<input type="submit" value="提交您的选择" name="submit">

javaBean简易计算器只能运行加法，哪里出错了？

您好，是不是断点的时候，发现operator永远是+。看了你的代码，在Calculate类中，你给了一个默认值：String operator="+";在jsp表单中 select name="count"去接收，把name改成operator试试能解决问题不？

String operator="+";改成    String operator=""; 进行debug