プルダウンから男子か女子を選択する

お父さんの身長とお母さんの身長を入力

form.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
     <%Integer childheight = (Integer)session.getAttribute("childheight");%>
    
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>

<!-- 子供の身長予測 -->
<form action="height" method="post">
	<div>
		<select name="gender">
		<option value="男子">男子</option>
		<option value="女子">女子</option>
	</select>
	</div>
	
	 <p>お父さんの身長<p/>
	 <input type="text" name="fatherheight"><br>
	 <p>お母さんの身長<p/>
	 <input type="text" name="motherheight"><br>
	 
	 <input type="submit" name="submit" value="送信" />
	
</form>

<% if(childheight != null) { %>
  <%=("お子様の予想身長は") %>
  <%=(childheight) %>
  <%=("cmです") %>
<% }%>

</body>
</html>

User.java

package beans;

public class User {
	
	private String gender;
	private String name;
	private int fatherheight;
	

	private int motherheight;

	public User(String name) {
			super();
			this.name = name;
		}

	public User() {
		
	}
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	  }
	
	public int getFatherheight() {
		return fatherheight;
	}

	public void setFatherheight(int fatherheight) {
		this.fatherheight = fatherheight;
	}

	public int getMotherheight() {
		return motherheight;
	}

	public void setMotherheight(int motherheight) {
		this.motherheight = motherheight;
	}
	
	public String getGender() {
		return gender;
	}

	public void setGender(String gender) {
		this.gender = gender;
	}


}

height.java

package サーブレット;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import beans.User;

/**
 * Servlet implementation class height
 */
@WebServlet("/height")
public class height extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public height() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		response.getWriter().append("Served at: ").append(request.getContextPath());
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html; charset=utf-8");
		
		String gender= request.getParameter("gender");
		String fatherheight= request.getParameter("fatherheight");
		String motherheight= request.getParameter("motherheight");
		
		int number1 = Integer.parseInt(fatherheight);
		int number2 = Integer.parseInt(motherheight);
		
		User u = new User();
		u.setGender(gender);
		u.setFatherheight(number1);
		u.setMotherheight(number2);
		int total = 0;
		if(u.getGender().equals("男子")) {
			total = (u.getFatherheight() + u.getMotherheight() + 13) / 2 + 2;
			
			HttpSession session = request.getSession();
			session.setAttribute("childheight",total);
			
			RequestDispatcher rd = request.getRequestDispatcher("form.jsp");
			rd.forward(request, response);
			
		} else {
			total = (u.getFatherheight() + u.getMotherheight() - 13) / 2 + 2;
			HttpSession session = request.getSession();
			session.setAttribute("childheight",total);
			
			RequestDispatcher rd = request.getRequestDispatcher("form.jsp");
			rd.forward(request, response);
			
		}
		
	}

}