Josson聚合符合条件的JSON键值方法

本文介绍了如何使用 Josson 库，在 Java 环境中，根据特定条件对 JSON 数组中的数据进行聚合。通过 Josson 提供的强大转换功能，可以高效地对 JSON 数据进行分组、映射和求和等操作，最终生成满足特定格式要求的 JSON 输出。

使用 Josson 聚合 JSON 数据

在处理 JSON 数据时，经常需要根据某些条件对数据进行聚合，例如，将具有相同用户ID、组名和片段的数据进行合并，并对特定字段进行求和。Josson 是一个强大的 JSON 处理库，可以方便地实现这种需求。

引入 Josson 库

首先，需要在项目中引入 Josson 库。可以通过 Maven 或 Gradle 添加依赖：

Maven:

    com.octomix
    josson
    最新版本 

Gradle:

implementation 'com.octomix:josson:最新版本' // 请替换为最新版本

示例代码

以下是一个使用 Josson 聚合 JSON 数据的示例：

import com.octomix.josson.Josson;
import com.octomix.josson.JsonNode;
import javax.json.JsonString;

public class JsonAggregation {

    public static void main(String[] args) throws Exception {
        String jsonString = "[" +
                "{\"userid\":\"CNAF01\",\"groupname\":\"Abhay\",\"segment\":\"CosCLFIN\",\"accountcode\":\"66CN-063CC\",\"symbol\":\"INX22\",\"exchange\":\"SGXFO\",\"expirydate\":\"24NOV2022\"," +
                "\"scripcode\":\"7536847\",\"securitytype\":\"FUT\",\"strikeprice\":0,\"opttype\":\"XX\",\"bfqty\":-107,\"bfrate\":18462.05,\"bfamt\":3950878.6999999997,\"buyqty\":21,\"sellqty\":59,\"netqty\":-38," +
                "\"cfqty\":-145,\"cfamt\":5358027.699999999,\"ltp\":\"18433.5\",\"grossmtm\":0,\"brokerageamt\":48,\"netmtm\":0,\"currency\":\"USD\",\"usdrate\":81.33,\"clientsharing\":50,\"broksharing\":0," +
                "\"comsharing\":50,\"multiplier\":2}," +
                "{\"userid\":\"CNAF01\",\"groupname\":\"Abhay\",\"segment\":\"CosCLFIN\",\"accountcode\":\"CW05\",\"symbol\":\"NIFTY\",\"exchange\":\"NSEFO\"," +
                "\"expirydate\":\"24NOV2022\",\"scripcode\":\"61349\",\"securitytype\":\"OPT\",\"strikeprice\":17800,\"opttype\":\"CE\",\"bfqty\":4050,\"bfrate\":673.3,\"bfamt\":-2726865,\"buyqty\":1650," +
                "\"sellqty\":300,\"netqty\":1350,\"cfqty\":5400,\"cfamt\":-3677257.5,\"ltp\":\"657.0\",\"grossmtm\":0,\"brokerageamt\":1038.81126525,\"netmtm\":0,\"currency\":\"INR\",\"usdrate\":1,\"clientsharing\":0," +
                "\"broksharing\":0,\"comsharing\":100,\"multiplier\":1}," +
                "{\"userid\":\"CNAF01\",\"groupname\":\"Abhay\",\"segment\":\"CosCLFIN\",\"accountcode\":\"CW05\",\"symbol\":\"NIFTY\",\"exchange\":\"NSEFO\"," +
                "\"expirydate\":\"24NOV2022\",\"scripcode\":\"61350\",\"securitytype\":\"OPT\",\"strikeprice\":17800,\"opttype\":\"PE\",\"bfqty\":-4050,\"bfrate\":14.7,\"bfamt\":59535,\"buyqty\":300,\"sellqty\":1650," +
                "\"netqty\":-1350,\"cfqty\":-5400,\"cfamt\":78900,\"ltp\":\"13.6\",\"grossmtm\":0,\"brokerageamt\":31.850901,\"netmtm\":0,\"currency\":\"INR\",\"usdrate\":1,\"clientsharing\":0,\"broksharing\":0," +
                "\"comsharing\":100,\"multiplier\":1}]";

        Josson josson = Josson.fromJsonString(jsonString);

        JsonNode node = josson.getNode(
                "group(map(userid,groupname,segment,accountcode,symbol,exchange,expirydate," +
                        "          currency,usdrate,clientsharing,broksharing,comsharing,multiplier))" +
                        ".map(key.userid," +
                        "     key.groupname," +
                        "     key.segment," +
                        "     key.accountcode," +
                        "     key.symbol," +
                        "     key.exchange," +
                        "     key.expirydate," +
                        "     key.currency," +
                        "     key.usdrate," +
                        "     key.clientsharing," +
                        "     key.broksharing," +
                        "     key.comsharing," +
                        "     key.multiplier," +
                        "     elements.bfqty.sum()," +
                        "     elements.bfrate.sum()," +
                        "     elements.bfamt.sum()," +
                        "     elements.buyqty.sum()," +
                        "     elements.sellqty.sum()," +
                        "     elements.netqty.sum()," +
                        "     elements.cfqty.sum()," +
                        "     elements.cfamt.sum()," +
                        "     elements.ltp.sum()," +
                        "     elements.grossmtm.sum()," +
                        "     elements.brokerageamt.sum()," +
                        "     elements.netmtm.sum())");
        System.out.println(node.toPrettyString());
    }
}

代码解释:

1. Josson.fromJsonString(jsonString): 将 JSON 字符串解析为 Josson 对象。
2. josson.getNode(...): 使用 Josson 表达式进行数据转换。
   • group(map(...)): 根据 map 中指定的键（userid, groupname, segment, accountcode, symbol, exchange, expirydate, currency, usdrate, clientsharing, broksharing, comsharing, multiplier）对 JSON 数组进行分组。
   • .map(...): 对每个分组后的元素进行映射，提取分组键的值，并对 elements 中的数值字段进行求和。elements 代表每个分组中的 JSON 对象数组。

输出结果

上述代码的输出结果如下：

[ {
  "userid" : "CNAF01",
  "groupname" : "Abhay",
  "segment" : "CosCLFIN",
  "accountcode" : "66CN-063CC",
  "symbol" : "INX22",
  "exchange" : "SGXFO",
  "expirydate" : "24NOV2022",
  "currency" : "USD",
  "usdrate" : 81.33,
  "clientsharing" : 50,
  "broksharing" : 0,
  "comsharing" : 50,
  "multiplier" : 2,
  "bfqty" : -107.0,
  "bfrate" : 18462.05,
  "bfamt" : 3950878.6999999997,
  "buyqty" : 21.0,
  "sellqty" : 59.0,
  "netqty" : -38.0,
  "cfqty" : -145.0,
  "cfamt" : 5358027.699999999,
  "ltp" : 18433.5,
  "grossmtm" : 0.0,
  "brokerageamt" : 48.0,
  "netmtm" : 0.0
}, {
  "userid" : "CNAF01",
  "groupname" : "Abhay",
  "segment" : "CosCLFIN",
  "accountcode" : "CW05",
  "symbol" : "NIFTY",
  "exchange" : "NSEFO",
  "expirydate" : "24NOV2022",
  "currency" : "INR",
  "usdrate" : 1,
  "clientsharing" : 0,
  "broksharing" : 0,
  "comsharing" : 100,
  "multiplier" : 1,
  "bfqty" : 0.0,
  "bfrate" : 688.0,
  "bfamt" : -2667330.0,
  "buyqty" : 1950.0,
  "sellqty" : 1950.0,
  "netqty" : 0.0,
  "cfqty" : 0.0,
  "cfamt" : -3598357.5,
  "ltp" : 670.6,
  "grossmtm" : 0.0,
  "brokerageamt" : 1070.66216625,
  "netmtm" : 0.0
} ]

注意事项

• 确保 Josson 库的版本是最新的，以便获得最佳性能和最新的功能。
• Josson 表达式需要仔细编写，确保分组和映射的键正确。
• 如果 JSON 数据量很大，可以考虑使用流式处理来提高性能。

总结

Josson 库提供了一种简洁而强大的方式来聚合 JSON 数据。通过使用 Josson 表达式，可以方便地对 JSON 数据进行分组、映射和求和等操作，从而满足各种数据处理需求。 在处理复杂的 JSON 数据转换时，Josson 是一个非常有用的工具。