java - 从数据库中选择数据并在jsp页面中显示

Question

我正在编写一个预订系统应用程序。用户可以在 JSP 页面的表格中查看音乐会和剧院等 Activity 。但是，我的代码不起作用。我想从数据库中选择数据并显示在 JSP 页面中。我该如何克服？我正在使用 NetBeans 进行编码。数据库包括 ID、类型、描述、城市、位置、日期。

音乐.html

<form action="music.jsp">
<style type="text/css">


    .tg  {border-collapse:collapse;border-spacing:0;margin:0px auto;}
    .tg td{font-family:Arial, sans-serif;font-size:14px;padding:10px      5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;}
    .tg th{font-family:Arial, sans-serif;font-size:14px;font-weight:normal;padding:10px 5px;border-style:solid;border-width:1px;overflow:hidden;word-break:normal;}
    .tg .tg-yw4l{vertical-align:top}
    th.tg-sort-header::-moz-selection { background:transparent; }th.tg-sort-header::selection      { background:transparent; }th.tg-sort-header { cursor:pointer; }table th.tg-sort-header:after {  content:'';  float:right;  margin-top:7px;  border-width:0 4px 4px;  border-style:solid;  border-color:#404040 transparent;  visibility:hidden;  }table th.tg-sort-header:hover:after {  visibility:visible;  }table th.tg-sort-desc:after,table th.tg-sort-asc:after,table th.tg-sort-asc:hover:after {  visibility:visible;  opacity:0.4;  }table th.tg-sort-desc:after {  border-bottom:none;  border-width:4px 4px 0;  }@media screen and (max-width: 767px) {.tg {width: auto !important;}.tg col {width: auto !important;}.tg-wrap {overflow-x: auto;-webkit-overflow-scrolling: touch;margin: auto 0px;}}</style>
<div class="tg-wrap"><table id="tg-E98gw" class="tg">
        <tr>
            <th class="tg-yw4l">ID</th>
            <th class="tg-yw4l">Type</th>
            <th class="tg-yw4l">Description</th>
            <th class="tg-yw4l">City</th>
            <th class="tg-yw4l">Location</th>
            <th class="tg-031e">Date</th>
        </tr>
        <tr>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
        </tr>
        <tr>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
        </tr>
        <tr>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
        </tr>
        <tr>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
            <td class="tg-yw4l"></td>
        </tr>
    </table></div>
<script type="text/javascript" charset="utf-8">var TgTableSort = window.TgTableSort || function(n, t){"use strict"; function r(n, t){for (var e = [], o = n.childNodes, i = 0; i < o.length; ++i){var u = o[i]; if ("." == t.substring(0, 1)){var a = t.substring(1); f(u, a) && e.push(u)} else u.nodeName.toLowerCase() == t && e.push(u); var c = r(u, t); e = e.concat(c)}return e}function e(n, t){var e = [], o = r(n, "tr"); return o.forEach(function(n){var o = r(n, "td"); t >= 0 && t < o.length && e.push(o[t])}), e}function o(n){return n.textContent || n.innerText || ""}function i(n){return n.innerHTML || ""}function u(n, t){var r = e(n, t); return r.map(o)}function a(n, t){var r = e(n, t); return r.map(i)}function c(n){var t = n.className || ""; return t.match(/\S+/g) || []}function f(n, t){return - 1 != c(n).indexOf(t)}function s(n, t){f(n, t) || (n.className += " " + t)}function d(n, t){if (f(n, t)){var r = c(n), e = r.indexOf(t); r.splice(e, 1), n.className = r.join(" ")}}function v(n){d(n, L), d(n, E)}function l(n, t, e){r(n, "." + E).map(v), r(n, "." + L).map(v), e == T?s(t, E):s(t, L)}function g(n){return function(t, r){var e = n * t.str.localeCompare(r.str); return 0 == e && (e = t.index - r.index), e}}function h(n){return function(t, r){var e = + t.str, o = + r.str; return e == o?t.index - r.index:n * (e - o)}}function m(n, t, r){var e = u(n, t), o = e.map(function(n, t){return{str:n, index:t}}), i = e && - 1 == e.map(isNaN).indexOf(!0), a = i?h(r):g(r); return o.sort(a), o.map(function(n){return n.index})}function p(n, t, r, o){for (var i = f(o, E)?N:T, u = m(n, r, i), c = 0; t > c; ++c){var s = e(n, c), d = a(n, c); s.forEach(function(n, t){n.innerHTML = d[u[t]]})}l(n, o, i)}function x(n, t){var r = t.length; t.forEach(function(t, e){t.addEventListener("click", function(){p(n, r, e, t)}), s(t, "tg-sort-header")})}var T = 1, N = - 1, E = "tg-sort-asc", L = "tg-sort-desc"; return function(t){var e = n.getElementById(t), o = r(e, "tr"), i = o.length > 0?r(o[0], "td"):[]; 0 == i.length && (i = r(o[0], "th")); for (var u = 1; u < o.length; ++u){var a = r(o[u], "td"); if (a.length != i.length)return}x(e, i)}}(document); document.addEventListener("DOMContentLoaded", function(n){TgTableSort("tg-E98gw")});</script>

音乐.jsp

    Class.forName("org.apache.derby.jdbc.ClientDriver").newInstance();
    String url = "jdbc:derby://localhost:1527/users";
    String username = "users";
    String password = "123";
    String query = "select * from activities";
    Connection conn = DriverManager.getConnection(url, username, password);
    Statement stmt = conn.createStatement();
    ResultSet rs = stmt.executeQuery(query);
    while (rs.next()) {



    <tr><td><%=rs.getInt("ID")%></td></tr>
    <tr><td><%=rs.getString("Type")%></td></tr>
    <tr><td><%=rs.getString("Description")%></td></tr>
    <tr><td><%=rs.getString("City")%></td></tr>
    <tr><td><%=rs.getString("Location")%></td></tr>
    <tr><td><%=rs.getString("Date")%></td></tr>
 }

Answer 1

假设调用了 music.jsp(我不知道项目结构，如果这两个页面在同一个文件夹中，等等)你正在创建一个全新的页面，结果，music.html 永远不会填充数据。因此，当您提交操作时，会在服务器端调用 music.jsp，执行代码，返回数据并在服务器端生成一个全新的 HTML 页面并将其发送回浏览器。 此外，看起来您创建的表是错误的，您读取的每一列都有一行，而不是一个数据库行中的所有列都有一行

<tr><td><%=rs.getInt("ID")%></td></tr>