Here you can find the source of setLookAndFeel()
public static void setLookAndFeel()
//package com.java2s; //License from project: Open Source License import javax.swing.UIManager; public class Main { public static void setLookAndFeel() { String lafStr = System.getProperty("anidev.pcds.laf", "<nimbus>"); switch (lafStr) { case "<nimbus>": lafStr = "com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel"; break; case "<system>": lafStr = UIManager.getSystemLookAndFeelClassName(); break; case "<cross>": lafStr = UIManager.getCrossPlatformLookAndFeelClassName(); break; }//from w w w . ja v a 2 s . c om try { UIManager.setLookAndFeel(lafStr); } catch (Exception e) { System.err.println("Error while setting " + lafStr + " L&F."); e.printStackTrace(); } } }