Question 191089 in Json Question posted in
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Parse JSON file that has nested keys

I have a JSON file that contains nested key-value pairs. My JSON file looks like this

{
   "TagName1":{
      "TestCaseName1":{
         "Status":"pass",
         "RunTime":"063045"
      },
      "TestCaseName2":{
         "Status":"fail",
         "RunTime":"064045"
      }
   },
   "TagName2":{
      "TestCaseName3":{
         "Status":"pass",
         "RunTime":"073045"
      },
      "TestCaseName4":{
         "Status":"fail",
         "RunTime":"074045"
      }
   }
}

I want to fetch the name of test cases based on their Status. Is there a way to do fetch nested key-values from JSON file?

I tried to solve this problem by using Reader and creating nested Hashmap of key-value pair, something like this

try{
    Gson gson = new Gson();
    Reader reader = Files.newBufferReader(Paths.get(filePath));
    HashMap<String, HashMap<String, HashMap<String,String>>> parsedJson = gson.fromJson(reader,HashMap.class);
}

I am struck at extracting the Status value. Is there a way to read the Status value and fetch the name of test case.

Tags:

4

Answers


  1. 0

    With the gson library it could be achived like this:

    final List<String> failedCases = JsonParser.parseString(jsonString)
        .getAsJsonObject().entrySet()
        .stream() // get stream of all json entries, i.e. tags
        .map(Map.Entry::getValue) // get stream of tag values
        .map(JsonElement::getAsJsonObject)
        .flatMap(e -> e.entrySet().stream()) // get stream of all test cases entries (name to value)
        .filter(e -> e.getValue().getAsJsonObject() // filter test cases with "failed" Status value
                .get("Status").getAsString().equals("fail")
        )
        .map(Map.Entry::getKey) // get test cases names
        .collect(Collectors.toList());
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  2. 0

    You can use JSONObjects to parse the document

    public static void main(String[] args) {
    // ...
    JSONObject jsonObject = new JSONObject(json);
    String targetStatus = "fail";
    List<String> testCaseName = getTestCaseNameByStatus(jsonObject, targetStatus);
    System.out.println("TestCases with Status '" + targetStatus + "': " + testCaseName);
}

private static List<String> getTestCaseNameByStatus(JSONObject jsonObject, String targetStatus) {
    List<String> testCases = new ArrayList<>();
    for (String tag : jsonObject.keySet()) {
        JSONObject tagObject = jsonObject.getJSONObject(tag);
        for (String testCase : tagObject.keySet()) {
            JSONObject testCaseObject = tagObject.getJSONObject(testCase);
            try {
                String status = testCaseObject.getString("Status");
                if (status.equalsIgnoreCase(targetStatus)) {
                    testCases.add(testCase);
                }
            } catch (JSONException jsonException) {
                System.out.printf("Status not found for TestCase {%s}, Skipping next", testCases);
            }
        }
    }
    return testCases;
}
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  3. 0

    @gdomo ‘s answer is pretty clean, here is how you can do the same with jackson

    Map<String, Map<String, TestCase>> json = objectMapper.readValue(file, new TypeReference<>() {});
    List<String> passes = json
            .values() // Lists of Entry { testCaseName: TestCase } grouped by tagName
            .stream().flatMap(entry -> entry.entrySet().stream())   // 1 list of all Entries { testCaseName : TestCase }
            .filter(entry -> entry.getValue().getStatus().equals("pass")) // filter entries that pass
            .map(Map.Entry::getKey)       // get the testCaseNames of entries that pass
            .toList();

    notice I am using a defined TestCase class "which is cleaner practice"

    public class TestCase {
    @JsonProperty(value = "Status")
    private String status;
    @JsonProperty(value = "RunTime")
    private String runtime;
    // getters, setters
}
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  4. 0

    You may try library Josson.

    https://github.com/octomix/josson

    Josson josson = Josson.fromJsonString(jsonString);
JsonNode node = josson.getNode("**.*[value.Status='pass']*.get(..key)");
System.out.println(node.toPrettyString());

    Output

    [ "TestCaseName1", "TestCaseName3" ]
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