Language.php

1. 9.x drupal/core/lib/Drupal/Core/Language/Language.php
2. 9.x drupal/core/lib/Drupal/Core/TypedData/Type/Language.php
3. 9.x drupal/core/modules/node/lib/Drupal/node/Plugin/views/field/Language.php
4. 9.x drupal/core/modules/user/lib/Drupal/user/Plugin/views/field/Language.php
5. 9.x drupal/core/modules/taxonomy/lib/Drupal/taxonomy/Plugin/views/field/Language.php

<?php

/**
 * @file
 * Definition of Drupal\Core\TypedData\Type\Language.
 */
namespace Drupal\Core\TypedData\Type;

use Drupal\Core\TypedData\ContextAwareInterface;
use Drupal\Core\TypedData\TypedDataInterface;
use InvalidArgumentException;

/**
 * Defines the 'language' data type.
 *
 * The plain value of a language is the language object, i.e. an instance of
 * Drupal\Core\Language\Language. For setting the value the language object or
 * the language code as string may be passed.
 *
 * Optionally, this class may be used as computed property, see the supported
 * settings below. E.g., it is used as 'language' property of language items.
 *
 * Supported settings (below the definition's 'settings' key) are:
 *  - langcode source: If used as computed property, the langcode property used
 *    to load the language object.
 */
class Language extends TypedData implements TypedDataInterface, ContextAwareInterface {

  /**
   * The name.
   *
   * @var string
   */
  protected $name;

  /**
   * The parent data structure.
   *
   * @var mixed
   */
  protected $parent;

  /**
   * The language code of the language if no 'langcode source' is used.
   *
   * @var string
   */
  protected $langcode;

  /**
   * Implements ContextAwareInterface::getName().
   */
  public function getName() {
    return $this->name;
  }

  /**
   * Implements ContextAwareInterface::setName().
   */
  public function setName($name) {
    $this->name = $name;
  }

  /**
   * Implements ContextAwareInterface::getParent().
   */
  public function getParent() {
    return $this->parent;
  }

  /**
   * Implements ContextAwareInterface::setParent().
   */
  public function setParent($parent) {
    $this->parent = $parent;
  }

  /**
   * Implements TypedDataInterface::getValue().
   */
  public function getValue() {
    $source = $this
      ->getLanguageCodeSource();
    $langcode = $source ? $source
      ->getValue() : $this->langcode;
    return $langcode ? language_load($langcode) : NULL;
  }

  /**
   * Helper to get the typed data object holding the source language code.
   *
   * @return \Drupal\Core\TypedData\TypedDataInterface|FALSE
   */
  protected function getLanguageCodeSource() {
    return !empty($this->definition['settings']['langcode source']) ? $this->parent
      ->get($this->definition['settings']['langcode source']) : FALSE;
  }

  /**
   * Implements TypedDataInterface::setValue().
   *
   * Both the langcode and the language object may be passed as value.
   */
  public function setValue($value) {

    // Support passing language objects.
    if (is_object($value)) {
      $value = $value->langcode;
    }
    elseif (isset($value) && !is_scalar($value)) {
      throw new InvalidArgumentException('Value is no valid langcode or language object.');
    }
    $source = $this
      ->getLanguageCodeSource();
    if ($source) {
      $source
        ->setValue($value);
    }
    else {
      $this->langcode = $value;
    }
  }

  /**
   * Implements TypedDataInterface::getString().
   */
  public function getString() {
    $language = $this
      ->getValue();
    return $language ? $language->name : '';
  }

  /**
   * Implements TypedDataInterface::validate().
   */
  public function validate() {

    // TODO: Implement validate() method.
  }

}