How to detect OS in Java

OSValidator.java

public class OSValidator {
 
	private static String OS = System.getProperty("os.name").toLowerCase();
 
	public static void main(String[] args) {
 
		System.out.println(OS);
 
		if (isWindows()) {
			System.out.println("This is Windows");
		} else if (isMac()) {
			System.out.println("This is Mac");
		} else if (isUnix()) {
			System.out.println("This is Unix or Linux");
		} else if (isSolaris()) {
			System.out.println("This is Solaris");
		} else {
			System.out.println("Your OS is not support!!");
		}
	}
 
	public static boolean isWindows() {
 
		return (OS.indexOf("win") >= 0);
 
	}
 
	public static boolean isMac() {
 
		return (OS.indexOf("mac") >= 0);
 
	}
 
	public static boolean isUnix() {
 
		return (OS.indexOf("nix") >= 0 || OS.indexOf("nux") >= 0 || OS.indexOf("aix") > 0 );
 
	}
 
	public static boolean isSolaris() {
 
		return (OS.indexOf("sunos") >= 0);
 
	}
 
}