java - 不能转换为 jakarta.servlet.Servlet

Question

我正在学习Java Web。我添加了依赖项并创建了一个 servlet 类。启动 tomcat 后，我​​收到这不是 servlet 并且无法强制转换为 jakarta.servlet.Servlet的错误。你能帮我找出根本原因吗？

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.PrintWriter;

public class HelloServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("hello servlet");
        PrintWriter writer = resp.getWriter();
        writer.print("hello,servlet");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        doGet(req,resp);
    }
}

标签： javawebtomcatservlets