How to POST raw whole JSON in the body of a Retrofit request?

Question

This question may have been asked before but no it was not definitively answered. How exactly does one post raw whole JSON inside the body of a Retrofit request?

See

Answer 1

Instead of classes we can also directly use the HashMap to send body parameters for example

interface Foo {
  @POST("/jayson")
  FooResponse postJson(@Body HashMap body);
}