HTML for Java组件应如何参考资源？

小编典典

HTML for Java组件应如何参考资源？

java

在以下情况下，HTML资源（样式表，图像等）可能无法正确加载
：

Swing应用程序。分发，或将其放入Jar文件时。
HTML在运行时生成。

如何在HTML中可靠地访问这些资源？

阅读 126

2020-11-01

共1个答案

小编典典

通过相对
引用链接资源（例如CSS或图像）的Jar文件中的HTML即可正常工作。

例如
本示例从
Jar中加载HTML（具有相对于图像的引用）。

import javax.swing.*;
import java.net.URL;

class ShowHtml {

    public static void main(String[] args) {
        final String address =
            "jar:http://pscode.org/jh/hs/object.jar!/popup_contents.html";
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                try {
                    URL url = new URL(address);
                    JEditorPane jep = new JEditorPane(url);
                    JFrame f = new JFrame("Show HTML in Jar");
                    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                    f.add(new JScrollPane(jep));
                    f.pack();
                    f.setSize(400,300);
                    f.setLocationByPlatform(true);
                    f.setVisible(true);
                } catch(Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
}

Screenshot

HTML

正在加载的HTML。

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<!--       
 *        Copyright (C) 1997  Sun Microsystems, Inc
 *                    All rights reserved.
 *          Notice of copyright on this source code 
 *          product does not indicate publication. 
 * 
 * RESTRICTED RIGHTS LEGEND: Use, duplication, or disclosure by 
 * the U.S. Government is subject to restrictions as set forth 
 * in subparagraph (c)(1)(ii) of the Rights in Technical Data
 * and Computer Software Clause at DFARS 252.227-7013 (Oct. 1988) 
 * and FAR 52.227-19 (c) (June 1987).
 *
 *    Sun Microsystems, Inc., 2550 Garcia Avenue,
 *    Mountain View, California 94043.
 *
-->
<HTML>
<HEAD>
<TITLE>
Editing Project Attributes
</TITLE>
</HEAD>
<BODY BGCOLOR="#ffffff">
<IMG SRC="images/popup_icon.gif" width="24" height="24"> <b>Popup Window</b>
<p>
Popup windows appear near the location from which they are
activated.  They are not contained in frames and thus
cannot be resized or moved by the user.  Popups are
dismissed by clicking anywhere in the help viewer.
<p>
Popup windows can be activated by clicking on a text object, 
graphic object, or JComponent button.  All three examples are
included in this demo.
<p>
<A HREF="popup_contents2.html">More...</A>
</body>
</html>

E.G. 2

对于动态创建的HTML，JRE可能会将类文件的
位置用作HTML的假定位置。但是，为了消除所有疑问，我们可以在中
指定base元素head。

import javax.swing.*;

class HtmlUsingBase {

    public static void main(String[] args) {
        final String htmlContent =
            "<html>" +
            "<head>" +
            "<base href='http://www.gravatar.com/'>" +
            "</head>" +
            "<body>" +
            "<h1>Image path from BASE</h1>" +
            "<img src='avatar/a1ab0af4997654345d7a9" +
            "49877f8037e?s=128&d=identicon&r=PG'" +
            " width='128' height='128'>" +
            "</body>" +
            "</html>";
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                JLabel label = new JLabel(htmlContent);
                JOptionPane.showMessageDialog(null, label);
            }
        });
    }
}

2020-11-01