src/Data/BizField.php
public function validate()
    {
        $ret = true;
        if ($this->validator)
            $ret = Expression::evaluateExpression($this->validator, $this->getDataObj());
        return $ret;
    }
public function validate()
    {
        $ret = true;
        if ($this->validator)
            $ret = Expression::evaluateExpression($this->validator, $this->getDataObj());
        return $ret;
    }
Check if the field has valid value

@return boolean true if validation is good