FieldInterface.php

1. 8.x drupal/core/lib/Drupal/Core/Entity/Field/FieldInterface.php
2. 8.x drupal/core/modules/field/lib/Drupal/field/FieldInterface.php

<?php

/**
 * @file
 * Contains \Drupal\Core\Entity\Field\FieldInterface.
 */
namespace Drupal\Core\Entity\Field;

use Drupal\Core\TypedData\AccessibleInterface;
use Drupal\Core\TypedData\ListInterface;

/**
 * Interface for fields, being lists of field items.
 *
 * This interface must be implemented by every entity field, whereas contained
 * field items must implement the FieldItemInterface.
 * Some methods of the fields are delegated to the first contained item, in
 * particular get() and set() as well as their magic equivalences.
 *
 * Optionally, a typed data object implementing
 * Drupal\Core\TypedData\TypedDataInterface may be passed to
 * ArrayAccess::offsetSet() instead of a plain value.
 *
 * When implementing this interface which extends Traversable, make sure to list
 * IteratorAggregate or Iterator before this interface in the implements clause.
 */
interface FieldInterface extends ListInterface, AccessibleInterface {

  /**
   * Filters out empty field items and re-numbers the item deltas.
   */
  public function filterEmptyValues();

  /**
   * Gets a property object from the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::get()
   */
  public function get($property_name);

  /**
   * Magic method: Gets a property value of to the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::__get()
   */
  public function __get($property_name);

  /**
   * Magic method: Sets a property value of the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::__set()
   */
  public function __set($property_name, $value);

  /**
   * Magic method: Determines whether a property of the first field item is set.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::__isset()
   */
  public function __isset($property_name);

  /**
   * Magic method: Unsets a property of the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::__unset()
   */
  public function __unset($property_name);

  /**
   * Gets the definition of a property of the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::getPropertyDefinition()
   */
  public function getPropertyDefinition($name);

  /**
   * Gets an array of property definitions of the first field item.
   *
   * @see \Drupal\Core\Entity\Field\FieldItemInterface::getPropertyDefinitions()
   */
  public function getPropertyDefinitions();

}