Generate random passwords length prefixed, with Java

The Java code described below, allows you to generate random passwords. It is possible to insert the password length using a command-line argument, or generate a default length password, such as 8 characters.

Code:

import java.util.*;

public class PasswordGenerator
{  
	static final String CHAR_SET = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcbefghijklmnopqrstuvwxyz0123456789[]+#&£$";

	public static void main(String[] args)
	{  
		int passwordLength = 8;
		if (args.length > 0) {
			try {
			passwordLength = Integer.parseInt(args[0]);
			} catch (NumberFormatException e) { }
		}
		
		String p = RandomString(CHAR_SET, passwordLength);
		System.out.println("Your password of "+passwordLength+" char is: " + p);
	}
	
	private static String RandomChars(String cs)
	{
		String rc = "";
		int length = cs.length();
		int index = (int) (Math.random() * length);
		return rc + cs.charAt(index);
	}
	
	private static String RandomString(String cs, int lenght)
	{
		String rs = "";
		for(int i=0; i<lenght; i++) 
		{
		rs+= RandomChars( cs );
		}
		return rs;	
	}
}

Example usage:

>java -cp . PasswordGenerator
Your password of 8 char is: u[#cof9U
>Exit code: 0

>java -cp . PasswordGenerator 12
Your password of 12 char is: Af3LBRYZ41za
>Exit code: 0

>java -cp . PasswordGenerator 16
Your password of 16 char is: b3vB+NCDqo0p0Iao
>Exit code: 0

>java -cp . PasswordGenerator 18
Your password of 18 char is: Uvb7C2WP2VYUTb8AW£
>Exit code: 0