Java 浏览器显示404错误

我不熟悉servlet，并使用eclipse制作了我的第一个servlet。我制作了Index.html、Login.java和WelcomeServlet.java。但每当我试图使用

localhost:8080/ServletExample/

它显示404错误。下面是代码

Index.html

WelcomeServlet.java

web.xml

---

您正在映射到“WelcomeServlet”而不是“ServletExample”

尝试转到localhost:8080/WelcomeServlet

编辑：对不起，后面不应该有斜杠

包java.io

---

为什么要将这一行放在WelcomeServlet.java中。

确保项目名称为ServletExample

---

localhost:8080/ServletExample/index.html

为什么在WelcomeServlet中将包名设置为java.io？删除它或在servlet类属性的web.xml中设置完整的类名。听起来您缺少servlet映射或上下文，点击或查看是否可以获得响应。知道了，web.xml中有一个错误。我已经改正了。谢谢你的提示。我相信你并没有打算在那个url中添加尾随斜杠

<form action="Login" method="post">  
Name:<input type="text" name="userName"/><br/>  
Password:<input type="password" name="userPass"/><br/>  
<input type="submit" value="login"/>  
</form>

public class Login extends HttpServlet {  

    public void doPost(HttpServletRequest request, HttpServletResponse response)  
            throws ServletException, IOException {  

        response.setContentType("text/html");  
        PrintWriter out = response.getWriter();  

        String n=request.getParameter("userName");  
        String p=request.getParameter("userPass");  

        if(p.equals("servlet")) {  
            RequestDispatcher rd=request.getRequestDispatcher("WelcomeServlet");  
            rd.forward(request, response);  
        } else {  
            out.print("Sorry UserName or Password Error!");  
            RequestDispatcher rd=request.getRequestDispatcher("/index.html");  
            rd.include(request, response);  
        }  
    }  
}  

package java.io;
import java.io.*;  
import javax.servlet.*;  
import javax.servlet.http.*;  

public class WelcomeServlet extends HttpServlet {  

    public void doPost(HttpServletRequest request, HttpServletResponse response)  
            throws ServletException, IOException {  

        response.setContentType("text/html");  
        PrintWriter out = response.getWriter();  

        String n=request.getParameter("userName");  
        out.print("Welcome "+n);  
    }  
}

<?xml version="1.0" encoding="UTF-8"?>

<web-app>  
    <servlet>  
        <servlet-name>Login</servlet-name>  
        <servlet-class>Login</servlet-class>  
    </servlet>  
    <servlet>  
        <servlet-name>WelcomeServlet</servlet-name>  
        <servlet-class>WelcomeServlet</servlet-class>  
    </servlet>  

    <servlet-mapping>  
        <servlet-name>Login</servlet-name>  
        <url-pattern>/Login</url-pattern>  
    </servlet-mapping>  
    <servlet-mapping>  
        <servlet-name>WelcomeServlet</servlet-name>  
        <url-pattern>/WelcomeServlet</url-pattern>  
    </servlet-mapping>  

    <welcome-file-list>  
        <welcome-file>index.html</welcome-file>  
    </welcome-file-list>  
</web-app>