Solution for the java puzzle from http://zeroturnaround.com/fun/magical-java-puzzle-pat-the-unicorns/

gistfile1.java

/**
 * Solution for the java puzzle from http://zeroturnaround.com/fun/magical-java-puzzle-pat-the-unicorns/
 */
public class Unicorn {

	private static int currentLine = 0;
	
	public static boolean pat() {
		int line = getExecutionLineFromMagicalLand();
		boolean isUniquePat = line != currentLine;
		currentLine = line;
		return isUniquePat;
	}

	private static int getExecutionLineFromMagicalLand() {
		Exception e = new Exception();
		e.fillInStackTrace();
		StackTraceElement[] stackTrace = e.getStackTrace();
		return stackTrace[2].getLineNumber();
	}
}