serializer

问题 im new here and i have a problem i can not solve. im getting this error in the debug in execution time: 05-02 11:56:07.539 18645-24466/com.appss.appssapp D/Retrofit﹕ java.lang.NullPointerException: Null pointer exception during instruction 'invoke-static {v0, v2}, java.util.ArrayList com.appss.appssapp.io.model.PostsResponse$MainResponse.access$002(com.appss.appssapp.io.model.PostsResponse$MainResponse, java.util.ArrayList) // method@19256' at com.appss.appssapp.io.model.PostsResponse

问题 I am working on a django project in which I am trying to fetch all the products having update_ts field greater than product_sync_ts from Product table from the server at a time, but since the number of products is large this requires a large amount of time to fetch all data.I am also returning the current time stamp along with the data.Now I want to paginate the results. My Previous code : Views.py @api_view(['GET']) def productlist(request, format=None): product_sync_ts = request.GET.get(

问题 I'm trying to allow a field that belongs to a related object to be readable and writable from a ModelSerializer. I have a model Group : class Group(models.Model): ... name = models.CharField(max_length=128) def get_language(self): line = self.line_set.all()[0] return line.language ... and corresponding serializer: class GroupSerializer(serializers.ModelSerializer): language = serializers.CharField(source='get_language') class Meta: model = Group fields = ('id', 'name', 'language') lookup

问题 I have a problem for deserializing another list inside Json message. My code work fine for read data like Project, Ref, Latitude ... I tried both method too : list and array. For example my JSON message: [{ "Project":"example", "Ref":"001BC50C70000A21", "Latitude":43.643166, "Longitude":1.454769, "ParkList": [{ "Id":"001BC50C70000A21P1", "State":1, "DateTime":"2018-02-15T08:07:18.987Z" }, { "Id":"001BC50C70000A21P2", "State":1, "DateTime":"2018-02-15T08:11:41.824Z" }] }] My class:

问题 I'm a begginer in Symfony 4 and I'm developing an API Rest. I want to create a PUT resource that can handle many update cases. In my case, I have a user with many properties but I will take an example with 3 properties to keep things simple : User { username, email, password } My PUT resource can be called in order to update Username, update Email or update Password. For example, to update Username, the user of my API will send a PUT request with only username : { username: "New username" }

问题 I have the following situation class MyModel(models.Model): key = models.CharField(max_length=255) value = models.TextField(max_length=255) category = models.CharField(max_length=4) mode = models.CharField(max_length=4) the fields key , category and mode are unique together . I have the following objects: m1 = MyModel(key='MODEL_KEY', value='1', category='CAT_1' mode='MODE_1') m2 = MyModel(key='MODEL_KEY', value='2', category='CAT_1' mode='MODE_2') m3 = MyModel(key='MODEL_KEY', value='1',

问题 I am trying to create a Django API for a list with pagination but have this error TypeError: Object of type 'Page' is not JSON serializable The following is my API code: @api_view(['POST']) def employee_get_list_by_page(request): # ----- YAML below for Swagger ----- """ description: employee_get_list_by_page parameters: - name: token type: string required: true location: form - name: page type: string required: true location: form - name: page_limit type: string required: true location: form

问题 I have this class public static class SomeClass { public SomeClass(String field) { this.field = field; } private final String field; public String getField() { return field; } } I have also this test ( edited ) @Test public void testStringifyMapOfObjects() { Map<String, SomeClass> original = Maps.newTreeMap(); original.put("first", new SomeClass("a")); original.put("second", new SomeClass("b")); String encoded = JsonUtil.toJson(original); Map<String, SomeClass> actual = JsonUtil.fromJson

问题 Seen lots of people with this same issue and no answers anywhere, so answering it myself here; When serializing an XML class that should have a prefix attached to it, the prefix is missing. [XmlRoot(ElementName = "Preadvice", Namespace = "http://www.wibble.com/PreadviceRequest")] public class Preadvice { } var XMLNameSpaces = new XmlSerializerNamespaces(); XMLNameSpaces.Add("isd", "http://www.wibble.com/PreadviceRequest"); And this is my serializing method; public static string

问题 I'm trying to use jaguar_serializer to convert my json string to its corresponding model object. I followed the steps as described in https://github.com/Jaguar-dart/jaguar_serializer. However, I keep getting this error when I run 'serializer build': 'package:jaguar_generator_config/src/generator.dart': error: line 17: illegal implicit access to receiver 'this' _config = loadYaml(new File(configFileName).readAsStringSync()); Here is my user.dart model: library models.user; import 'package