// Metal风格 (默认)
String lookAndFeel = "javax.swing.plaf.metal.MetalLookAndFeel";
UIManager.setLookAndFee(lookAndFeel);
// Windows风格
String lookAndFeel = "com.sun.java.swing.plaf.windows.WindowsLookAndFeel";
UIManager.setLookAndFee(lookAndFeel);
// Windows Classic风格
String lookAndFeel = "com.sun.java.swing.plaf.windows.WindowsClassicLookAndFeel";
UIManager.setLookAndFee(lookAndFeel);
// Motif风格
String lookAndFeel = "com.sun.java.swing.plaf.motif.MotifLookAndFeel";
UIManager.setLookAndFeel(lookAndFeel);
// 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);
// 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);
// 可跨平台的默认风格
String lookAndFeel = UIManager.getCrossPlatformLookAndFeelClassName();
UIManager.setLookAndFeel(lookAndFeel);
// 当前系统的风格
String lookAndFeel = UIManager.getSystemLookAndFeelClassName();
UIManager.setLookAndFeel(lookAndFeel);
原文：https://blog.51cto.com/14221100/2394353