To compile Contract file and generate abi and bin files
solc < contract >.sol --bin --abi --optimize -o
To generate wrapper class of the compiled contract files
web3j solidity generate .bin .abi -o /path/to/src/main/java -p packagename
To create a rinkeby test wallet
web3j wallet create
To run geth client on your machine
geth --rpcapi personal,db,eth,net,web3 --rpc --rinkeby
Get your private key from here
Add some test ether to your wallet
Check your test ether balance