In this example, the platform used is Magento, but I believe this is a generic question related to Object Oriented Programming.
When a page or API URL is called, the first class to be instantiated will then instantiate other classes, and so forth. I need to change a setting in an instance of one class (there will only be one instance) from within another class.
For example, I am working in class Praxis_Rest_ProductsController::getAction() and want to do this:
(existing instance of Varien_Db_Adapter_Pdo_Mysql)->setDebug(true);
I know for sure that the connection class is Varien_Db_Adapter_Pdo_Mysql and that this is instantiated already, and only once.
How do I do this? Is this possible?
-- EDIT --
@Andrej Ludinovskov below posted a great solution if I know the object name, but in my case, I'm in a spot in the coding which has no relationship too it. In fact it might be 7-10 different classes in the stack downstream where that instantiated object is called; but I do know that class was instantiated and only once for that matter. In this case I'm trying to find $object when all I know is that it's an instance of Varien_Db_Adapter_Pdo_Mysql
