use LWP;
use HTML::Parser;
$url = 'xx';
$ua = LWP::UserAgent->new();
$form = $ua->get($url) or die "Couldn't fetch $url";
$form->is_success() or die $form->message();
print $form->content(); 

my $session = "";
my $parser = HTML::Parser->new;
$parser->handler(start => \&start_handler,"tagname,attr,self");
$parser->parse( $form->content );

print $session;

sub start_handler{
    my ($tag,$attr,$self) = @_;
    return unless $tag eq 'form';
    
    my $action = $attr->{action};
    ($session) = $action =~ /jsessionid=(.*)/;
}