Questions on the GroundClient packages

[litong-x]

According to the Ground Wiki, it shows that we can use the client library to generate the data context.

GroundClient client = new GroundClient(host, port);

int managerId = client.createNode("manager");
int engineerId = client.createNode("engineer");

Is the GroundClient packages? Also, When I want to use POST API to generate the data, it always reply bad request. Then, where can I get start with?

Thanks.