bitcoin core RPC vs bitcoin libraries What is the main difference between using one of the bitcoin libraries to create a project and using bitcoin core json RPC API directly by connecting to your node for everything?
If the library has no full node support, which part exactly requires you to use a fullnode and which part can be done without full node?
https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)#Java The link mentioned for library doesn't work here but I found BitcoinJ and it mentioned that you don't need local copy of bitcoin core so how does everything happen without node?
In simplified terms...
Libraries work more like a calculator that simply process the data you feed it.
The JSON-RPC API can not only process the data you feed it, but also gives you access to the data you need.