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swing这个java类路径设置正确吗?

我真的不知道我错过了什么。我已经花了很多时间阅读如何设置类路径,但这仍然不起作用,在这一点上,我确信这一定是一些琐碎的事情,让我无法理解

我正在尝试使用swingradiance libraries来更改swing应用程序的外观。我按照build documentation生成jar文件,当这些文件不起作用时,我下载并尝试使用prebuilt binaries。我向开发人员提出了一个问题,并确认我正确地遵循了getting started instructions。演示代码如下:

import java.awt.*;
import javax.swing.*;
import java.awt.image.*;

public class Walkthrough extends JFrame {
  public Walkthrough() {
    super("Sample app");
    this.setLayout(new FlowLayout());
    this.add(new JButton("button"));
    this.add(new JCheckBox("check"));
    this.add(new JLabel("label"));

    this.setIconImage(new BufferedImage(1, 1, BufferedImage.TYPE_4BYTE_ABGR));
    this.setSize(new Dimension(250, 80));
    this.setLocationRelativeTo(null);
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }

  public static void main(String[] args) {
    JFrame.setDefaultLookAndFeelDecorated(true);

    SwingUtilities.invokeLater(() -> {
        Walkthrough w = new Walkthrough();
        w.setVisible(true);
    });
  }
}

代码首先用javac Walkthrough.java编译,然后用java Walkthrough执行。这个很好用。接下来,使用radiance jar来更改外观,这是通过将swing.defaultlaf属性设置为使用来自radiance的蒙皮来完成的。这就是它不起作用的地方

我将所有必需的jar复制到tmp目录中,其中演练示例位于tmp之外。然后,我尝试按如下方式运行应用程序:

java -Dswing.defaultlaf=org.pushingpixels.substance.api.skin.SubstanceBusinessLookAndFeel -cp .:tmp/radiance-substance-2.5-SNAPSHOT.jar:tmp/radiance-trident-2.5-SNAPSHOT.jar:tmp/radiance-neon-2.5-SNAPSHOT.jar Walkthrough 

这导致了以下例外情况:

Exception in thread "AWT-EventQueue-0" java.lang.Error: Cannot load org.pushingpixels.substance.api.skin.SubstanceBusinessLookAndFeel
    at java.desktop/javax.swing.UIManager.initializeDefaultLAF(UIManager.java:1406)
    at java.desktop/javax.swing.UIManager.initialize(UIManager.java:1517)
    at java.desktop/javax.swing.UIManager.maybeInitialize(UIManager.java:1483)
    at java.desktop/javax.swing.UIManager.getUI(UIManager.java:1056)
    at java.desktop/javax.swing.JPanel.updateUI(JPanel.java:126)
    at java.desktop/javax.swing.JPanel.<init>(JPanel.java:86)
    at java.desktop/javax.swing.JPanel.<init>(JPanel.java:109)
    at java.desktop/javax.swing.JPanel.<init>(JPanel.java:117)
    at java.desktop/javax.swing.JRootPane.createGlassPane(JRootPane.java:521)
    at java.desktop/javax.swing.JRootPane.<init>(JRootPane.java:348)
    at java.desktop/javax.swing.JFrame.createRootPane(JFrame.java:279)
    at java.desktop/javax.swing.JFrame.frameInit(JFrame.java:258)
    at java.desktop/javax.swing.JFrame.<init>(JFrame.java:225)
    at Walkthrough.<init>(Walkthrough.java:7)
    at Walkthrough.lambda$main$0(Walkthrough.java:23)
    at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:313)
    at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:770)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
    at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
    at java.base/java.security.AccessController.doPrivileged(AccessController.java:389)
    at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
    at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:740)
    at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
    at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
    at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

组织。推动像素。物质应用程序编程接口。皮SubstanceBusinessLookAndFeel生活在radiance-substance-2.5-SNAPSHOT中。罐子我已经用jar tvf确认了它确实存在:

jar tvf radiance-substance-2.5-SNAPSHOT.jar | grep SubstanceBusinessLookAndFeel
   548 Fri Feb 01 00:00:00 GMT 1980 org/pushingpixels/substance/api/skin/SubstanceBusinessLookAndFeel.class

所以在这一点上,我肯定我把类路径弄乱了,但我不知道是什么。我在Fedora 28上,我的java版本是:

java version "12.0.1" 2019-04-16
Java(TM) SE Runtime Environment (build 12.0.1+12)
Java HotSpot(TM) 64-Bit Server VM (build 12.0.1+12, mixed mode, sharing)

共 (1) 个答案

  1. # 1 楼答案

    这与类路径无关,而是与jar库本身有关。我观察到,在我的机器上,默认情况下字体没有消除锯齿(Fedora 28,使用i3 gaps作为窗口管理器)。我想知道这是否有某种关联,并阅读了Java运行时环境字体。本质上,字体是这样的:

    enter image description here

    但是使用这个系统属性启动应用程序:-Dawt.useSystemAAFontSettings=on修复了以下问题:

    enter image description here

    事实证明,在启动辐射漫游时设置此属性可以使其工作:

    java -Dawt.useSystemAAFontSettings=on -Dswing.defaultlaf=org.pushingpixels.substance.api.skin.SubstanceBusinessLookAndFeel -cp .:tmp/radiance-substance-2.5-SNAPSHOT.jar:tmp/radiance-trident-2.5-SNAPSHOT.jar:tmp/radiance-neon-2.5-SNAPSHOT.jar Walkthrough

    enter image description here

    删除此属性会导致Java无法加载org的错误。推动像素。物质应用程序编程接口。皮实质性的商业外观和感觉

    阅读here有更多信息。我假设,因为我定制了Fedora 28设置(我不使用gnome),所以我没有运行gnome-settings-daemon,Java使用它来获取系统默认值,而这在某种程度上是Radiance的问题。。。?不确定

    我已经通知了Radiance开发者。如果他提供反馈,我会更新这个答案

    更新 开发人员确认这个库中有一个bug。已经修好了