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javahtmltomcatservletsservlet-3.0

I am a beginner and I just started to learn java servlets and jsp. Can someone help me find the error in this code?

Here is the HTML code:

<!DOCTYPE html>
<html>
    <head>
        <meta charset="UTF-8">
        <title>Add Two Numbers</title>
    </head>
    <body>
        <h1>Please enter numbers</h1>
        <form action="AddNum" method="post">
            Enter 1st Number :<br>
            <input type=text name=num1><br><br>
            Enter 2nd Number :<br>
            <input type=text name=num2><br><br>
            <input type="submit">
        </form>
    </body>
</html>

Here is the java code:

package com.package1;

import java.io.IOException;
import java.io.PrintWriter;

import jakarta.servlet.ServletException;
import jakarta.servlet.annotation.WebServlet;
import jakarta.servlet.http.HttpServlet;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;

@WebServlet("/AddNum")
public class Addserv extends HttpServlet{
    
    private static final long serialVersionUID = 1L;

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        // TODO Auto-generated method stub
        super.doPost(req, resp);
        int no1=Integer.parseInt(req.getParameter("num1"));
        int no2=Integer.parseInt(req.getParameter("num2"));
        int sum=no1+no2;
        
        PrintWriter out = resp.getWriter();
        
        out.println(sum);
    }
    
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doPost(req,resp);
    }

}

even though I used the doPost method, I am getting this error message.

enter image description here

I am using Eclipse for IDE and Apache Tomcat 10.1.30 as my server

I tried to add a doget method(still in code as I believe it doesn't negatively alter anything)

Tried changing the method of the form to "get", same 405 error with get instead of post.

Solution

  • The default implementation of doPost is to return an HTTP 405 error, and it should be overridden to get a different behavior. However, by calling super.getPost, you're generating that error again.

    Long story short - remove the call to the super's method and you should be OK:

    @Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    // call to super.doPost remove from here
    int no1=Integer.parseInt(req.getParameter("num1"));
    int no2=Integer.parseInt(req.getParameter("num2"));
    int sum=no1+no2;
    
    PrintWriter out = resp.getWriter();
    
    out.println(sum);
}