Java check if string contains only letters

Q:how to check if string contains only alphabets in java

/**
 * @author lautturi.com
 * Java example: determine whether string contains only alphabets in java
 */

import java.util.*;

public class Lautturi {
	public static void main(String[] args) {
		
		String str = "HelloLauJava";

		if( str.matches("[a-zA-Z]+")) {
			System.out.println("The string contains only alphabets!");
		}

	}
}