How to create a node with type?using dgraph4j

To facilitate better answering of questions, if you have a question, please fill in the following info. Otherwise, please delete the template.

What I want to do

i had create a type in ratel,i’m using dgraph4j,but i don’t know how to create a node with type ,
it makes i can’t delete any node using <0xf11168064b01135b> * * .

What I did

this is the example i found

  // Create data
  Person p = new Person(); = "Alice";

  // Serialize it
  String json = gson.toJson(p);

  // Run mutation
  Mutation mutation =