为啥输出值是null？请老师帮忙检查下

package com.imooc.servlet.context;
 
import java.io.IOException;
 
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
/**
 * Servlet implementation class ServletContextInitServlet
 */
@WebServlet("/context/initcontext")
public class ServletContextInitServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
        
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServletContextInitServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
 
    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        ServletContext context= request.getServletContext();
        context.setAttribute("copyright", "©2020 imooc.com All Rights Reserved 京ICP备 12003892号-11");
        context.setAttribute("title", "慕课网，程序员的梦工厂");
        response.getWriter().print("int sccuess");
    }
 
}

**************************************************************

package com.imooc.servlet.context;
 
import java.io.IOException;
 
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
/**
 * Servlet implementation class ServletContextDefualtServlet
 */
@WebServlet("/context/defulat")
public class ServletContextDefualtServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
        
    /**
     * @see HttpServlet#HttpServlet()
     */
    public ServletContextDefualtServlet() {
        super();
        // TODO Auto-generated constructor stub
    }
 
    /**
     * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
     */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        ServletContext context= (ServletContext)request.getServletContext();
        String copyright= (String) context.getAttribute("copyright");
        String title = (String) context.getAttribute("title");
        response.setContentType("text/html;charset=utf-8");
        response.getWriter().println("<h1>"+copyright+"</h1>"+title);
         
    }
 
}