I'm using Java (web3j). I have some users and I want to give address to each user. How to generate new address in an ethereum wallet? For example I can generate lots of address from bitcoin wallet. Is it possible to generate new address in one ethereum wallet seems like bitcoin?
If it isn't possible then how can I assign different address to users? Must I create new wallet for every user and save them to a directory? Thanks.
You don't have to save wallet to file. You can extract the low-level code yourself. Check my answer here Generate private key and address using web3j
I solved myself. Every wallet file has to save to file. It isn't same as bitcoin. Every wallet has only one address.
You should not store wallet privkey on server.
Instead, you should let your user load their own private key. Or use metamask/mist.
If you really want to create accounts on trigger,you better secure both the brige between your app and the ethereum node you have,and the node itself (secure Nginx or apache rule for the geth instance etc) because you don't want your node or privkey pool hacked.
