Incorrect example for EntityGenerator

There is incorrect example in this page
http://www.doctrine-project.org/api/orm/2.0/doctrine/orm/tools/entitygenerator.html

Generic class used to generate PHP5 entity classes from ClassMetadataInfo instances
[php] $classes = $em->getClassMetadataFactory()->getAllMetadata();
$generator = new \Doctrine\ORM\Tools\EntityGenerator(); $generator->setGenerateAnnotations(true); $generator->setGenerateStubMethods(true); $generator->setRegenerateEntityIfExists(false); $generator->setUpdateEntityIfExists(true); $generator->generate($classes, '/path/to/generate/entities');

Fatal error: Call to undefined method Doctrine\ORM\EntityManager::getClassMetadataFactory()