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Get Blog from the Repository¶

Lets take a look into the BlogRepository and travel into the inner core of our little action island.

<?php
namespace FriendsOfTYPO3\BlogExample\Domain\Repository;

class BlogRepository extends \TYPO3\CMS\Extbase\Persistence\Repository
{

}

The BlogRepository does not need any own code since all methods which are most commonly used are already implemented in the parent class \TYPO3\CMS\Extbase\Persistence\Repository. In the controller, you saw the call to findAll(), to retrieve all blog objects which is one of the methods available by default.

The way a repository works is much like a library of a university which works in the following way:

You tell an employee of the library to find a book matching certain criteria. After a few minutes till days you get the corresponding book. In this case it doesn't matter to you if the book is right below the counter, in a shelf, in the cellar, or is not even printed yet. It is only important that you get the book. Remarks made with a pencil by you will be added permanently when you return the book.

That is translated to a repository: Via a repository you tell a method to find an object matching certain criteria. After a few milliseconds till seconds you receive the corresponding object. In this case you don't care where the object is stored. Practically it even doesn't matter if the object is stored in the memory, must be fetched from the hard drive, is retrieved via web service from another server, or is instantiated for the first time. The only important thing is that the object is instantiated and delivered to you. Object attributes changed by you will be stored when you leave the extension.

Note

Although you don't need to implement your own logic extbase expects an existing class.