how to generate a random string in java

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

import java.util.*;

public class Lautturi {

	public static void main(String[] args) {

		int randomStrLen = 10;
		
		String chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
		Random rnd = new Random();
		StringBuilder sb = new StringBuilder(randomStrLen);
		for (int i = 0; i < randomStrLen; i++)
			sb.append(chars.charAt(rnd.nextInt(chars.length())));
		String randomStr = sb.toString();
		System.out.println(randomStr);
		
	}
}

output:

3YFSF7wk9s