how to capitalize the first letter of a string in java

/**
 * @author lautturi.com
 * Java example: uppercase the first letter in string
 */

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		String str = "java world";
		String capStr = str.substring(0, 1).toUpperCase() + str.substring(1);
		System.out.println(capStr);
		
	}
}

output:

Java world