I am looking to use some of the management admin API's found here: https://github.com/ethereum/go-ethereum/wiki/Management-APIs but unfortunately, the web3j library does not support the calls that I need, hence I need to run the calls myself.
I am running 3 nodes on a private network on localhost ports 8545, 8546, and 8547.
Unfortunately, I can't find a single example online on how to make a curl request in java. Can anyone please help? Any example would be fine so I understand the structure. An example could be on finding the block number: https://github.com/ethereumproject/go-ethereum/wiki/JSON-RPC#eth_blocknumber