Запрос на удаление данных с веб-сервера

public class RestClient {
    private static final String JSON_URL = "http://localhost:8080/expenses";
    public List<Expense> getExpensesFromServer() {
        return parseJSON(getHttp());
    }
    public List<Expense> deleteExpensesFromServer(List<Expense> expenses){return parseJSONDel(deletehttp(expenses));}
    public void sendExpensesToServer(Expense expense) {
        postHttp(makeJson(expense));
    }
    public List<Expense> parseJSONDel(String json) {
        List<Expense> list = null;
        try {
            ObjectMapper mapper = new ObjectMapper();
            TypeFactory typeFactory = mapper.getTypeFactory();
            CollectionType collectionType = typeFactory.
                    constructCollectionType(List.class, Expense.class);
            list = mapper.readValue(json, collectionType);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }
 
    public List<Expense> parseJSON(String json) {
        List<Expense> list = null;
        try {
            ObjectMapper mapper = new ObjectMapper();
            TypeFactory typeFactory = mapper.getTypeFactory();
            CollectionType collectionType = typeFactory.
                    constructCollectionType(List.class, Expense.class);
            list = mapper.readValue(json, collectionType);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }
 
    private String makeJson(Expense expense) {
        String result = "";
        try {
            ObjectMapper mapper = new ObjectMapper();
            result = mapper.writeValueAsString(expense);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return result;
    }
    private String deletehttp(List<Expense> expenses) {
        HttpDelete httpDelete = new HttpDelete(JSON_URL);
        CloseableHttpClient httpClient = HttpClients.createDefault();
        try {
            httpDelete.setHeader(HttpHeaders.CONTENT_TYPE,"application/json");
            if(expenses!=null && !expenses.isEmpty()){
                for(Expense expense:expenses){
                    httpDelete.removeHeader((Header)expense);
                }
            }
            httpClient.execute(httpDelete);
 
        } catch (IOException e) {
            e.printStackTrace();
        }
         return "";
    }
 
}
}