Java Swing To Set custom Look and Feel to UI

if ( setcmd txt is "Windows")
{
lfName = "com.sun.java.swing.plaf.windows.WindowsLookAndFeel";
}

try
{
UIManager.setLookAndFeel(lfName);
}
catch (UnsupportedLookAndFeelException ex1)
{
System.err.println("Unsupported LookAndFeel: " + lnfName);
}