code: public String getInstanceEndpoint(String entityName, String groupId, String id) {
  		String edp = getCollectionEndpoint(entityName, groupId);
  
  		if (id != null && !id.isEmpty()) {
  			edp += "/" + id;
  		}
  
  		return edp;
  	}
docs: Return the path to the instance endpoint
  
  @param entity
  name
  @param customer
  group id
  @param entity
  id
  @return instance path