CODEWITHSUNDEEP
javajsonfastjsonfastjson2
Enno Shioji
Enno Shioji

Reputation: 26882

How to ask fastjson2 to deserialize decimal/int array as primitive array (not list of boxed numbers)

Is it possible to have fastjson2 deserialize a JSON array into a primitive array of float/ints? Ideally without boxing/unboxing the numbers.

I found that there is a option JSONReader.Feature.UseDoubleForDecimals which gets me half way there, but I can't figure out how to have it use primitive arrays instead of List<Integer> etc.

It must use fastjson2 (so using Jackson is not an option).

This code:

void test() {
    enum TestEnum {
        A, B, C
    }
    // Prepare data
    Map<TestEnum, Object> testData = Map.of(
            TestEnum.A, "test",
            TestEnum.B, new String[]{"test1", "test2"},
            TestEnum.C, new float[]{1.0f, 2.0f, 3.0f}
    );

    // Serialize
    String serialized = JSON.toJSONString(testData);
    System.out.println("Serialized: " + serialized);

    JSONObject read = JSON.parseObject(serialized, JSONReader.Feature.UseDoubleForDecimals);
    for (Map.Entry<String, Object> stringObjectEntry : read.entrySet()) {
        System.out.println(stringObjectEntry.getKey() + " " + stringObjectEntry.getValue().getClass() + " " + (stringObjectEntry.getValue() instanceof List));
    }
    System.out.println(read);
}

Prints:

Serialized: {"A":"test","C":[1.0,2.0,3.0],"B":["test1","test2"]}
A class java.lang.String false
C class com.alibaba.fastjson2.JSONArray true
B class com.alibaba.fastjson2.JSONArray true
{"A":"test","C":[1.0,2.0,3.0],"B":["test1","test2"]}

But I want it to use float[] for the key TestEnum.C when it's deserialized, not JSONArray (List).

Upvotes: 0

Views: 55

Answers (0)

Related Questions