Date.php

1. 8.x drupal/core/lib/Drupal/Core/Datetime/Date.php
2. 8.x drupal/core/lib/Drupal/Core/TypedData/Type/Date.php
3. 8.x drupal/core/vendor/easyrdf/easyrdf/lib/EasyRdf/Literal/Date.php
4. 8.x drupal/core/vendor/symfony/validator/Symfony/Component/Validator/Constraints/Date.php
5. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/field/Date.php
6. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/argument/Date.php
7. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/sort/Date.php
8. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/filter/Date.php

<?php

/**
 * @file
 * Contains \Drupal\Core\TypedData\Type\Date.
 */
namespace Drupal\Core\TypedData\Type;

use Drupal\Core\Datetime\DrupalDateTime;
use Drupal\Core\TypedData\TypedData;
use InvalidArgumentException;

/**
 * The date data type.
 *
 * The plain value of a date is an instance of the DrupalDateTime class. For
 * setting the value any value supported by the __construct() of the
 * DrupalDateTime class will work, including a DateTime object, a timestamp, a
 * string date, or an array of date parts.
 */
class Date extends TypedData {

  /**
   * The data value.
   *
   * @var DateTime
   */
  protected $value;

  /**
   * Overrides TypedData::setValue().
   */
  public function setValue($value, $notify = TRUE) {

    // Notify the parent of any changes to be made.
    if ($notify && isset($this->parent)) {
      $this->parent
        ->onChange($this->name);
    }

    // Don't try to create a date from an empty value.
    // It would default to the current time.
    if (!isset($value)) {
      $this->value = $value;
    }
    else {
      $this->value = $value instanceof DrupalDateTime ? $value : new DrupalDateTime($value);
    }
  }

}