ExtraDataBundle/Entity/Traits/ExtraDataTrait.php

<?php

namespace ExtraDataBundle\Entity\Traits;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Validator\Constraints as Assert;

trait ExtraDataTrait
{

    /**
     * @var string $extraData
     *
     * @ORM\Column(type="text", nullable=true)
     * 
     * @Assert\Callback(
     *  callback={"ExtraDataBundle\Validator\JSONValidator", "validate"}, 
     *  payload={"field"="extraData"}
     * )
     */
    private $extraData;

    /**
     * @return string
     */
    public function getExtraData()
    {
        return $this->extraData;
    }

    /**
     * @param string $extraData
     * 
     * @return $this
     */
    public function setExtraData($extraData = null)
    {
        $this->extraData = $extraData;

        return $this;
    }

}