public class Servlet1 extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("get"); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("post"); doGet(request, response); }}用户在浏览器地址栏中键入正确的请求 URL 并回车后,在控制台上显示的结果是()。
时间: 2024-04-27 16:25:38 浏览: 15
如果用户在浏览器中输入正确的请求 URL 并回车,那么控制台将会输出 "get"。这是因为在这个 Servlet 中,doGet() 方法处理 HTTP GET 请求,而 doPost() 方法处理 HTTP POST 请求。如果浏览器发送的是 GET 请求,那么服务器会调用 doGet() 方法并输出 "get"。如果浏览器发送的是 POST 请求,那么服务器会调用 doPost() 方法并输出 "post" 和 "get",但是这个 Servlet 中的 doPost() 方法并没有被正确关闭,所以 doPost() 方法的代码实际上是被包含在 doGet() 方法中的,所以在任何情况下都会输出 "get"。
相关问题
public class Servlet1 extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("get"); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("post"); doGet(request, response); }}控制台显示结果是什么
如果你在浏览器中使用 GET 请求方式访问 Servlet1,那么控制台将输出 "get"。如果你在浏览器中使用 POST 请求方式访问 Servlet1,那么控制台将输出 "post" 和 "get"。
这是因为在给定的代码中,doGet() 方法输出 "get",doPost() 方法输出 "post",并且在 doPost() 方法中调用了 doGet() 方法。因此,无论使用 GET 还是 POST 请求方式,都会调用 doGet() 方法并输出 "get"。如果使用 POST 请求方式,还会输出 "post"。
请帮我解释以下代码:@WebServlet("/demo2") public class SessionDemo2 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(); System.out.println(session); Object username = session.getAttribute("username"); System.out.println(username); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } }
这段代码是一个使用Java Servlet技术实现的Servlet类,它的URL映射路径为"/demo2"。当客户端向服务器发送一个GET请求时,Servlet会调用doGet()方法来响应请求,当客户端向服务器发送一个POST请求时,Servlet会调用doPost()方法来响应请求。在这个Servlet中,doGet()方法中获取了一个HttpSession对象,并通过getAttribute()方法获取了这个Session中名为"username"的属性值,最后将其打印到控制台上。如果这个属性不存在,它将打印null。这段代码可以用于演示如何在Java Servlet中使用Session对象来存储和获取用户信息。
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