创建Cookie对象

import javax.servlet.ServletException;
import javax.servlet.http.Cookie;
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 CreatCookieServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        this.doPost(req, resp);
    }
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //创建cookie对象
        Cookie cookie = new Cookie("key","gengrenlong");
        //将cookie写回客户端
        resp.addCookie(cookie);
        PrintWriter printWriter = resp.getWriter();
        printWriter.println("creat cookie success");
        printWriter.flush();
        printWriter.close();
    }
}