Test $2(8$ points$).$ Show the output of the following program:

class

int $cnt=0$;

public $x$ increment $()\{$

cnt$++$;

return this;

$\}$

$\}$

public class Test$02\{$

public static void main$($String$[]$ args$)\{$

$xa=$ new $x()$;

a$.$increment $().$ increment $().$ increment $()$;

System.out.println$($a$.$cnt$)$;

$\}$

$\}$