Question

我正在使用JavaBeans在JSP中做一个shool项目。不幸的是，我们的老师并不熟悉。有一个index.jsp，其中包含Bean的所有entre＃34;问题＆＃34;显示。这个bean包含一个ArrayList of Issues。名为Issue的Bean包含问题的数据，例如时间和地点。 servlet控制add-Issue-operation，它将创建一个新的Issue并将其添加到ArrayList。如果单击index.jsp上列出的问题，您将被重新扫描到包含详细信息的页面。这个包含详细信息和聊天。因此，有一个名为ChatEntry的类/ Bean，可以保存聊天，并且是每个问题的一部分。

这里是AddIssueServlet：

package servlets;

import java.io.IOException;
import java.time.LocalDateTime;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import beans.Issue;
import beans.Issues;

@WebServlet("/addIssue")
public class AddIssueServlet extends HttpServlet {
private static final long serialVersionUID = 1L;

protected void doPost(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException {
    String category = request.getParameter("category");
    String title = request.getParameter("title");
    int maxParticipants = 
    Integer.parseInt(request.getParameter("maxParticipants"));
    int currParticipants = 1;
    String description = request.getParameter("description");
    String place = request.getParameter("place");

    String[] startTime = request.getParameter("startTime").split(":");
    String[] endTime = request.getParameter("endTime").split(":");
    String[] startDate = request.getParameter("startDate").split("-");
    String[] endDate = request.getParameter("endDate").split("-");

    LocalDateTime startDateTime = 
    LocalDateTime.of(Integer.parseInt(startDate[0]), 
    Integer.parseInt(startDate[1]),
            Integer.parseInt(startDate[2]), Integer.parseInt(startTime[0]), 
    Integer.parseInt(startTime[1]));
    LocalDateTime endDateTime = 
    LocalDateTime.of(Integer.parseInt(endDate[0]), 
    Integer.parseInt(endDate[1]),
            Integer.parseInt(endDate[2]), Integer.parseInt(endTime[0]), 
     Integer.parseInt(endTime[1]));

    Issue newIssue = new Issue(category, title, description, 
    maxParticipants, currParticipants, startDateTime,
            endDateTime, place);
    Issues issues = (Issues) getServletContext().getAttribute("issues");
    int id = issues.addIssue(newIssue);

    response.sendRedirect("/lobbyDetail.jsp?id=" + id);
}

}

details.jsp：

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@taglib prefix="t" tagdir="/WEB-INF/tags"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<jsp:useBean id="issues" class="beans.Issues" scope="application" />

<!DOCTYPE html>
<script src="../js/scripts.js" type="text/javascript" charset="utf-8"
async defer></script>
<t:layout>
<t:issue issue="${issues.issues[param.id]}"></t:issue>

<div id="chat">
    <form action="lobbyDetail" name="lobbyDetail" method="post">
        <textarea rows="50" cols="50" id="textAreaChatHistory"
            readonly="readonly"> <jsp:getProperty property="getChat"
                name="getChat" /></textarea>
        <input type="text" id="username" name="username"
            placeholder="Ihr Nutzername">
        <textarea rows="2" cols="50">Ihre Nachricht</textarea>
        <input type="submit" value="Absenden">
    </form>
</div>
</t:layout>

ChatServlet：

package servlets;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


import beans.Issue;
import beans.Issues;


@WebServlet("/ChatServerServlet")
public class ChatServerServlet extends HttpServlet
{
private static final long serialVersionUID = 1L;


/**
 * Default constructor.
 */
public ChatServerServlet()
{

}

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse 
response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse 
response) throws ServletException, IOException
{
}
HttpServlet#doPost(HttpServletRequest request, HttpServletResponse 
response)

protected void doPost(HttpServletRequest request, HttpServletResponse 
response) throws ServletException, IOException
{
    String username = request.getParameter("username");
    String userMessage = request.getParameter("userMessage");

//        How to get the"right" bean?
//        Bean.addChatEntry(username, userMessage);

}
}

如何获取单击按钮的详细信息页面中使用的Bean，以便将聊天保存到正确的问题-Bean / Object？

我用Google搜索，阅读并观看YouToube四天，但没有找到解决方案。

我们只允许使用JSP和JavaBeans。

如何在JSP中使用Bean

0 个答案: