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                        /JAVA遇見HTML——Servlet篇

照著打的報錯了請問什么原因？

jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
??? pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
??? <h1>1111</h1>
??? <hr>
??? <a href="yuiop/Helloworld">q</a>
</body>
</html>

java

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.catalina.connector.Response;

public class Helloworld extends HttpServlet {

?@Override
?protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
??// TODO Auto-generated method stub
??System.out.println("1234");
??PrintWriter out = response.getWriter();
??out.println("dsadsadsadsadsaa");
?}

?@Override
?protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
??// TODO Auto-generated method stub
??
?}
???
}

xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
? <display-name>yuiop</display-name>
? <welcome-file-list>
??? <welcome-file>index.html</welcome-file>
??? <welcome-file>index.htm</welcome-file>
??? <welcome-file>index.jsp</welcome-file>
??? <welcome-file>default.html</welcome-file>
??? <welcome-file>default.htm</welcome-file>
??? <welcome-file>default.jsp</welcome-file>
? </welcome-file-list>
???? <servlet>
???????? <servlet-name>Helloworld</servlet-name>
???????? <servlet-class>yuiop</servlet-class>
???? </servlet>
???? <servlet-mapping>
???????? <servlet-name>Helloworld</servlet-name>
???????? <url-pattern>/yuiop/Helloworld</url-pattern>
???? </servlet-mapping>
????
</web-app>