做了一個filter過濾器，每次評論，将值存入session，然後跳轉頁面過過濾器，判斷是否髒話，但是每次評論都延遲了，就是說這次評論，評出來上一次的評論内容。
錯誤代碼如下
<%--
Created by IntelliJ IDEA.
User: admin
Date: 2020/11/2
Time: 15:17
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<h1>成功</h1>
<form action="word" method="post">
<p>不能說 日 （日是髒話）</p><br/>
發表評論<input type="text" name="word"><br/>
<input type="submit" value="發表">
</form>
</body>
</html>
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import java.io.IOException;
public class AdminFilter implements Filter {
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
String requestURI = httpServletRequest.getRequestURI();
HttpSession session = httpServletRequest.getSession();
Object user = session.getAttribute("user");
Object userword = session.getAttribute("userword");
servletRequest.setCharacterEncoding("utf-8");
//髒話辨識
if (userword != null)) {
if ("日".equals(userword.toString())) {
System.out.println("髒話辨識啟動");
// httpServletRequest.getSession().setAttribute("userword",null);
servletRequest.getRequestDispatcher("/wordfail.jsp").forward(servletRequest, servletResponse);
} else {
// httpServletRequest.getSession().setAttribute("userword",null);
servletRequest.getRequestDispatcher("/wordsuccess.jsp").forward(servletRequest, servletResponse);
}
}
//是否登入過濾
if (requestURI.endsWith("/") || user != null || requestURI.endsWith("/index.jsp") || requestURI.endsWith("/login")) {
System.out.println("11111111");
filterChain.doFilter(servletRequest, servletResponse);
} else {
servletRequest.getRequestDispatcher("/index.jsp").forward(servletRequest, servletResponse);
}
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void destroy() {
}
}
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
public class word extends HttpServlet {
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String userword=req.getParameter("word");
req.getSession().setAttribute("userword",userword);
req.getRequestDispatcher("/wordsuccess.jsp").forward(req,resp);
// resp.sendRedirect("index.jsp");
}
}
這是因為，過濾器為排除word類頁面網址，這樣每次評論完點發表，送出給/word都會再次進入過濾器，又做一次判斷發表。
是以将/word加入過濾器剔除
但是這樣就變成每次直接跳轉成功
這是因為
重點！！！！
我用的方法是請求轉發，是以網址不改變，是以被過濾器剔除了。
是以将方法改為重定向
問題解決，完美
![JavaSE學習筆記-Day1[圖]](data:image/gif;base64,R0lGODlhAQABAIAAAP///wAAACwAAAAAAQABAAACAkQBADs=)