java - 在Java Servlet中将ResultSet设置为Json

尝试从数据库获取数据并存储在JSON对象中，如下所示：

try {
            JsonObject jsonResponse = new JsonObject();
            JsonArray data = new JsonArray();
            JsonArray row = new JsonArray();
            PrintWriter out = response.getWriter();

            Connection con = OracleDBConnection.getConnection();
            String query = "Select * from CUSTOMER_DEMOGRAPHICS";
            Statement st = con.createStatement();
            ResultSet rSet = st.executeQuery(query);

            while (rSet.next())
            {
                row.add(new JsonPrimitive(rSet.getString("COUNTRY")));
                row.add(new JsonPrimitive(rSet.getString("STATE")));
                row.add(new JsonPrimitive(rSet.getString("CITY")));
                data.add(row);
            }

            jsonResponse.add("ResponseData", data);
            response.setContentType("application/json");
            response.setCharacterEncoding("UTF-8");

            out.print(jsonResponse);
            out.flush();
            System.out.println(jsonResponse);

        } catch (Exception e) {
            e.printStackTrace();
        }
    }

数据库中的表结构：

COUNTRY     STATE       CITY
================================
AUSTRALIA   VICTORIA    MELBOURNE
AUSTRALIA   NEW SOUTH   SYDNEY

问题是当我打印json时，它按如下所示为每一行打印两次，而不是一次。

{"ResponseData":
[["AUSTRALIA","VICTORIA","MELBOURNE","AUSTRALIA ","NEW SOUTH WALES","SYDNEY"],
["AUSTRALIA","VICTORIA","MELBOURNE","AUSTRALIA ","NEW SOUTH WALES","SYDNEY"]]}

最佳答案

您正在创建单行，并将其添加到数组两次。线

JsonArray row = new JsonArray();

应该在循环内。不在外面