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<?php

namespace Bitrix\Forum\Internals;

use Bitrix\Forum\ForumTable;
use Bitrix\Forum\Forum;
use Bitrix\Forum\Permission;
use Bitrix\Main\Config\Option;
use Bitrix\Main\Event;
use Bitrix\Main\SystemException;

abstract class Entity implements \ArrayAccess
{
	use \Bitrix\Forum\Internals\EntityBaseMethods;

/** @var int */
	protected $authorId;
	/** @var Forum */
	protected $forum;
	/** @var array */
	protected $data;

public function __construct($id)
	{
		$this->id = $id;
		if ($id <= 0)
		{
			throw new \Bitrix\Main\ArgumentNullException(static::class . " empty id.");
		}
		$this->init();

$this->forum = new Forum($this->data["FORUM_ID"]);

if ($this->authorId === null)
		{
			throw new \Bitrix\Main\ArgumentNullException("Author id must be defined.");
		}

$this->errorCollection = new \Bitrix\Main\ErrorCollection();
	}
	/**
	 * Init Entity data, Forum
	 * @return $this
	 */
	abstract protected function init();

public function getId()
	{
		return $this->id;
	}

public function getForumId()
	{
		return $this->forum->getId();
	}

public function getAuthorId()
	{
		return $this->authorId;
	}

abstract public function edit(array $fields);

abstract public static function create($parentObject, array $fields);
}

/var/www/axolotl/data/www/kirov.axolotls.ru/bitrix/modules/forum/lib/internals/entity.php