使用 Josson 库聚合 JSON 数组中满足特定条件的键值-java教程-PHP中文网

使用 josson 库聚合 json 数组中满足特定条件的键值

本文介绍了如何使用 Josson 库，根据特定条件（如 userid、groupname、segment 等字段相同）对 JSON 数组中的数据进行聚合，并对数值类型的键进行求和操作，最终生成新的 JSON 数组。通过详细的代码示例和步骤说明，帮助读者理解 Josson 库的使用方法，并能灵活应用于实际的数据处理场景。

在处理 JSON 数据时，经常会遇到需要根据某些字段的值进行分组，然后对其他字段进行聚合计算的需求。例如，在金融数据分析中，可能需要根据用户ID、交易品种等信息，统计用户的总交易量、总交易额等。手动编写代码实现这些功能比较繁琐，容易出错。 Josson 库提供了一种简洁高效的方式来完成这类任务。

Josson 简介

Josson 是一个强大的 JSON 处理库，它提供了一种简洁的语法，可以通过链式调用完成复杂的 JSON 数据转换和查询操作。它特别擅长于处理嵌套的 JSON 数据结构，并支持各种聚合函数，例如 sum(), count(), avg() 等。

使用 Josson 进行 JSON 数据聚合

下面将通过一个具体的例子，演示如何使用 Josson 库对 JSON 数组进行聚合操作。

1. 引入 Josson 库

首先，需要在项目中引入 Josson 库。如果使用 Maven，可以在 pom.xml 文件中添加以下依赖：

<dependency>
    <groupId>com.octomix</groupId>
    <artifactId>josson</artifactId>
    <version>最新版本</version>
</dependency>

登录后复制

请将 "最新版本" 替换为 Josson 库的最新版本号。

2. JSON 数据准备

Find JSON Path Online

Easily find JSON paths within JSON objects using our intuitive Json Path Finder

查看详情

假设有如下 JSON 数组，需要根据 userid、groupname、segment、accountcode、symbol、exchange 和 expirydate 字段进行分组，并对 bfqty、bfrate、bfamt、buyqty、sellqty、netqty、cfqty、cfamt、ltp、grossmtm、brokerageamt 和 netmtm 字段进行求和：

[
  {
    "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
  }
]

登录后复制

3. 使用 Josson 进行转换

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

public class JossonAggregation {

    public static void main(String[] args) {
        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());
    }
}

登录后复制

代码解释:

Josson.fromJsonString(jsonString): 将 JSON 字符串解析为 Josson 对象。
group(map(userid,groupname,segment,accountcode,symbol,exchange,expirydate,currency,usdrate,clientsharing,broksharing,comsharing,multiplier)): 这部分代码定义了分组的依据。 group() 函数根据 map() 函数中指定的字段进行分组。 map() 函数用于提取每个 JSON 对象中指定的字段，并将它们组合成一个键。
.map(key.userid, key.groupname, ...): 这部分代码定义了输出结果的结构。 key.userid 表示使用分组键中的 userid 字段作为输出结果中的 userid 字段的值。 elements.bfqty.sum() 表示对每个分组中的 bfqty 字段进行求和，并将结果作为输出结果中的 bfqty 字段的值。

4. 输出结果

运行上述代码，将得到以下输出结果：

[ {
  "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
} ]

登录后复制

可以看到，Josson 库成功地根据指定的字段对 JSON 数组进行了分组，并对数值类型的字段进行了求和操作。