感谢大佬：https://blog.csdn.net/u010022051/article/details/52671860

注：具体详情请查阅Java API文档

/**

* 设置图形界面外观

* java的图形界面外观有3种,默认是java的金属外观,还有就是windows系统,motif系统外观.

* 1、Metal风格 (默认) UIManager.setLookAndFeel(“javax.swing.plaf.metal.MetalLookAndFeel”);

* 2、Windows风格 UIManager.setLookAndFeel(“com.sun.java.swing.plaf.windows.WindowsLookAndFeel”);

* 3、Windows Classic风格 UIManager.setLookAndFeel(“com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel”);

* 4、Motif风格UIManager.setLookAndFeel(“com.sun.java.swing.plaf.motif.MotifLookAndFeel”);

* 5、Mac风格 (需要在相关的操作系统上方可实现) String lookAndFeel = “com.sun.java.swing.plaf.mac.MacLookAndFeel”;UIManager.setLookAndFeel(lookAndFeel);

* 6、GTK风格 (需要在相关的操作系统上方可实现) String lookAndFeel = “com.sun.java.swing.plaf.gtk.GTKLookAndFeel”;UIManager.setLookAndFeel(lookAndFeel);

* 7、可跨平台的默认风格 String lookAndFeel = UIManager.getCrossPlatformLookAndFeelClassName(); UIManager.setLookAndFeel(lookAndFeel);

* 8、当前系统的风格 String lookAndFeel = UIManager.getSystemLookAndFeelClassName(); UIManager.setLookAndFeel(lookAndFeel);

这是设置图形界面外观的.java的图形界面外观有3种,默认是java的金属外观,还有就是windows系统,motif系统外观.

UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());

这是把外观设置成你所使用的平台的外观,也就是你这个程序在哪个平台运行,显示的窗口,对话框外观将是哪个平台的外观.

补充：

https://blog.csdn.net/changemyself/article/details/675473

https://blog.csdn.net/sinat_37765046/article/details/79077644

https://blog.csdn.net/starcrm/article/details/52576379

Substance使用： https://blog.csdn.net/nospeak/article/details/83802445

Substance下载：https://www.mvnjar.com/org.java.net.substance/substance/jar.html