public function testCheck()
 {
     $t = new SecurityToken();
     $t->setValue(null);
     $this->assertFalse($t->check('invalidtoken'), 'Any token is invalid if no token is stored');
     $t->setValue(null);
     $this->assertFalse($t->check(null), 'NULL token is invalid if no token is stored');
     $t->setValue('mytoken');
     $this->assertFalse($t->check('invalidtoken'), 'Invalid token returns false');
     $t->setValue('mytoken');
     $this->assertTrue($t->check('mytoken'), 'Valid token returns true');
 }