Attention

TYPO3 v8 has reached its end-of-life March 31st, 2020 and is not maintained by the community anymore. Looking for a stable version? Use the version switch on the top left.

There is no further ELTS support. It is recommended that you upgrade your project and use a supported version of TYPO3.

Singletons

TYPO3 supports singleton patterns for classes. Singletons are instantiated only once per HTTP request regardless of the number of calls to GeneralUtility::makeInstance(). To use a singleton pattern, a class must implement the SingletonInterface:

namespace Vendor\MyNamespace;

class MySingletonClass implements \TYPO3\CMS\Core\SingletonInterface
{
    …
}

This interface has no methods to implement.