Like in topic - do I have to make the whole save/load system from scratch for everything I want to save/load or is there any easier and faster way to handle this?
What do you mean by system? Also what type of things are you trying to save?
By system I mean way to save the whole game state - entities, settings and then load them from files.
Usually, if you want full control over your save/load system, the best way to do it is from scratch or just using Java serialization. There are other options, but I already stated them in this topic (which might be a good read).
It all depends on the control you want. Most of these systems are already pretty fast. Reading from a file is one of the most basic computer commands after all. The speed issue comes from how you plan to organize your data. But to answer your question directly.
Just use a .txt file to write/read data.
Yeah a .txt should keep things very simple for you
I just use Java serialization.
Cas 
I use an seriziable Named-Binary-Node-Tree.
Very useful and no problems with changing classes.
Reasons the system is useful.
-
Small and Compact
-
Data is saved in Binary form, very small
-
Little-to-No overhead while saving/loading
-
Binary Tree is structured like an XML document
-
No problems when classes undego major changes
-
Longor1996