how to reverse a string efficiently in java

/**
 * @author lautturi.com 
 * Java example: reverse a string in java
 */

import java.util.*;

public class Lautturi {
	public static void main(String[] args) {
		String string = "welcome to lauttur! java world!";
		StringBuilder sb = new StringBuilder();
		sb.append(string);
		sb.reverse();
		String reverseString = sb.toString();
		System.out.println(reverseString);
	}
}

output:

!dlrow avaj !ruttual ot emoclew