How to call geth mining through java code manually ?

Question

I am using web3j and Geth and created a private network. However, I want to do the mining manually whenever required, since don't want to jam the server when I am in the development phase. For that, I found JsonRpc2_0Geth update in web3j and used it. However, mining does not start. Please help me where I am going wrong.

pom.xml

<dependency>
        <groupId>org.web3j</groupId>
        <artifactId>core</artifactId>
        <version>4.0.1</version>
    </dependency>
    <dependency>
        <groupId>org.web3j</groupId>
        <artifactId>geth</artifactId>
        <version>4.0.1</version>
    </dependency>

Then, i called the Geth aPI through my java file as follows:

static public Web3j web3j = Web3j.build(new HttpService("<geth ip>:<port>"));
static public JsonRpc2_0Geth geth = new JsonRpc2_0Geth(new HttpService("<geth ip>:<port>"));
geth.minerStart(1000);

Answer 1

Posting to RPC URL is a way to start mining from any language

{"jsonrpc":"2.0","method":"miner_start","params":[1],"id":74}

I.e. post this data to RPC URL.

Command line example is :

curl -X POST --data '{"jsonrpc":"2.0","method":"miner_start","params":[4],"id":74}' localhost:8545

https://github.com/ethereum/go-ethereum/wiki/Management-APIs

This page has example of sending a POST request from Java.

https://www.mkyong.com/java/how-to-send-http-request-getpost-in-java/