Error message
Deprecated function: unserialize(): Passing null to parameter #1 ($data) of type string is deprecated in Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (line 474 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (Line: 428) Drupal\Core\Entity\Sql\SqlContentEntityStorage->getFromStorage() (Line: 394) Drupal\Core\Entity\Sql\SqlContentEntityStorage->doLoadMultiple() (Line: 312) Drupal\Core\Entity\EntityStorageBase->loadMultiple() (Line: 513) Drupal\Core\Entity\EntityBase::loadMultiple() (Line: 2553) Drupal\api\Formatter::otherProjectsLink() (Line: 2706) Drupal\api\Formatter::preparePageListingVariables() (Line: 441) Drupal\api\Controller\OutputController->branchExplicitRoute() call_user_func_array() (Line: 123) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 637) Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 181) Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53) Drupal\Core\StackMiddleware\Session->handle() (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 201) Drupal\page_cache\StackMiddleware\PageCache->fetch() (Line: 138) Drupal\page_cache\StackMiddleware\PageCache->lookup() (Line: 87) Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 741) Drupal\Core\DrupalKernel->handle() (Line: 19)Deprecated function: unserialize(): Passing null to parameter #1 ($data) of type string is deprecated in Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (line 474 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (Line: 428) Drupal\Core\Entity\Sql\SqlContentEntityStorage->getFromStorage() (Line: 394) Drupal\Core\Entity\Sql\SqlContentEntityStorage->doLoadMultiple() (Line: 312) Drupal\Core\Entity\EntityStorageBase->loadMultiple() (Line: 513) Drupal\Core\Entity\EntityBase::loadMultiple() (Line: 2553) Drupal\api\Formatter::otherProjectsLink() (Line: 2706) Drupal\api\Formatter::preparePageListingVariables() (Line: 441) Drupal\api\Controller\OutputController->branchExplicitRoute() call_user_func_array() (Line: 123) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 637) Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 181) Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53) Drupal\Core\StackMiddleware\Session->handle() (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 201) Drupal\page_cache\StackMiddleware\PageCache->fetch() (Line: 138) Drupal\page_cache\StackMiddleware\PageCache->lookup() (Line: 87) Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 741) Drupal\Core\DrupalKernel->handle() (Line: 19)Deprecated function: unserialize(): Passing null to parameter #1 ($data) of type string is deprecated in Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (line 474 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (Line: 428) Drupal\Core\Entity\Sql\SqlContentEntityStorage->getFromStorage() (Line: 394) Drupal\Core\Entity\Sql\SqlContentEntityStorage->doLoadMultiple() (Line: 312) Drupal\Core\Entity\EntityStorageBase->loadMultiple() (Line: 513) Drupal\Core\Entity\EntityBase::loadMultiple() (Line: 2553) Drupal\api\Formatter::otherProjectsLink() (Line: 2706) Drupal\api\Formatter::preparePageListingVariables() (Line: 441) Drupal\api\Controller\OutputController->branchExplicitRoute() call_user_func_array() (Line: 123) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 637) Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 181) Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53) Drupal\Core\StackMiddleware\Session->handle() (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 201) Drupal\page_cache\StackMiddleware\PageCache->fetch() (Line: 138) Drupal\page_cache\StackMiddleware\PageCache->lookup() (Line: 87) Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 741) Drupal\Core\DrupalKernel->handle() (Line: 19)Deprecated function: unserialize(): Passing null to parameter #1 ($data) of type string is deprecated in Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (line 474 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (Line: 428) Drupal\Core\Entity\Sql\SqlContentEntityStorage->getFromStorage() (Line: 394) Drupal\Core\Entity\Sql\SqlContentEntityStorage->doLoadMultiple() (Line: 312) Drupal\Core\Entity\EntityStorageBase->loadMultiple() (Line: 513) Drupal\Core\Entity\EntityBase::loadMultiple() (Line: 2553) Drupal\api\Formatter::otherProjectsLink() (Line: 2706) Drupal\api\Formatter::preparePageListingVariables() (Line: 441) Drupal\api\Controller\OutputController->branchExplicitRoute() call_user_func_array() (Line: 123) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 637) Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 181) Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53) Drupal\Core\StackMiddleware\Session->handle() (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 201) Drupal\page_cache\StackMiddleware\PageCache->fetch() (Line: 138) Drupal\page_cache\StackMiddleware\PageCache->lookup() (Line: 87) Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 741) Drupal\Core\DrupalKernel->handle() (Line: 19)Deprecated function: unserialize(): Passing null to parameter #1 ($data) of type string is deprecated in Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (line 474 of core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php).
Drupal\Core\Entity\Sql\SqlContentEntityStorage->mapFromStorageRecords() (Line: 428) Drupal\Core\Entity\Sql\SqlContentEntityStorage->getFromStorage() (Line: 394) Drupal\Core\Entity\Sql\SqlContentEntityStorage->doLoadMultiple() (Line: 312) Drupal\Core\Entity\EntityStorageBase->loadMultiple() (Line: 513) Drupal\Core\Entity\EntityBase::loadMultiple() (Line: 2553) Drupal\api\Formatter::otherProjectsLink() (Line: 2706) Drupal\api\Formatter::preparePageListingVariables() (Line: 441) Drupal\api\Controller\OutputController->branchExplicitRoute() call_user_func_array() (Line: 123) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 637) Drupal\Core\Render\Renderer->executeInRenderContext() (Line: 124) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->wrapControllerExecutionInRenderContext() (Line: 97) Drupal\Core\EventSubscriber\EarlyRenderingControllerWrapperSubscriber->Drupal\Core\EventSubscriber\{closure}() (Line: 181) Symfony\Component\HttpKernel\HttpKernel->handleRaw() (Line: 76) Symfony\Component\HttpKernel\HttpKernel->handle() (Line: 53) Drupal\Core\StackMiddleware\Session->handle() (Line: 48) Drupal\Core\StackMiddleware\KernelPreHandle->handle() (Line: 28) Drupal\Core\StackMiddleware\ContentLength->handle() (Line: 32) Drupal\big_pipe\StackMiddleware\ContentLength->handle() (Line: 201) Drupal\page_cache\StackMiddleware\PageCache->fetch() (Line: 138) Drupal\page_cache\StackMiddleware\PageCache->lookup() (Line: 87) Drupal\page_cache\StackMiddleware\PageCache->handle() (Line: 48) Drupal\Core\StackMiddleware\ReverseProxyMiddleware->handle() (Line: 51) Drupal\Core\StackMiddleware\NegotiationMiddleware->handle() (Line: 36) Drupal\Core\StackMiddleware\AjaxPageState->handle() (Line: 51) Drupal\Core\StackMiddleware\StackedHttpKernel->handle() (Line: 741) Drupal\Core\DrupalKernel->handle() (Line: 19)- You are browsing documentation for drupal 9.5.x, which is not supported anymore. Read the updated version of this page for drupal 11.x (the latest version).
Classes, traits, and interfaces - 9.5.x - drupal
Introduction to classes
A lot of the PHP code in Drupal is object oriented (OO), making use of PHP classes, interfaces, and traits. See the Objected-oriented programming conventions for more information.
See also
Objected-oriented programming conventions
File
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core/
core.api.php, line 1523
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