Java: null problem solving

Problem description:

.UnsupportedOperationException: null

Problem analysis:

1. UseGsonSerialize, but usefastjsonDeserialization is performed, because fastjson does not support Gson serializing the json data after LocalDate and LocalDateTime types, an error is reported.

        List<TestModel> testModelList = new ArrayList<>();



        TestModel testModel = new TestModel();



        (());



        (());



        (testModel);



        Gson gson = new Gson();



        String jsonStr = (testModelList);



        testModelList = (jsonStr, );

AI writing code

[{"localDate":{"year":2022,"month":5,"day":18},"localDateTime":{"date":{"year":2022,"month":5,"day":18},"time":{"hour":10,"minute":27,"second":34,"nano":979527900}}}]
AI writing code

Solution:

1. Deserialization using Gson.

        List<TestModel> testModelList = new ArrayList<>();



        TestModel testModel = new TestModel();



        (());



        (());



        (testModel);



        Gson gson = new Gson();



        String jsonStr = (testModelList);



        testModelList = (jsonStr, new TypeToken<List<TestModel>>() {



        }.getType());

AI writing code

2. The serialization and deserialization methods remain unchanged. LocalDate and LocalDateTime types are converted toStringtype.

        List<TestModel> testModelList = new ArrayList<>();



        TestModel testModel = new TestModel();



        (().format(("yyyy-MM-dd")));



        (().format(("yyyy-MM-dd HH:mm:ss")));



        (testModel);



        Gson gson = new Gson();



        String jsonStr = (testModelList);



        testModelList = (jsonStr, );

AI writing code