My JavaFX application handles large amounts Json data. How do I visualize the simplest way JSON data in a table that also must be editable?
The obvious method is to convert JSON to Java objects but for a number of reasons I would like to avoid that.
UPDATE, from comment below I have tried this(feeding ListView directly).
string json = "[{\"fields\":{\"VENDOR\":[\"xxx""],\"TYPE\":[\"yyyyy\"]}, \"path\": \"C:\"}]";
#FXML
private ListView idListView;
JsonReader reader = Json.createReader(new StringReader(json));
public JsonArray myItems = reader.readArray();
reader.close();
public ObservableList<JsonObject> olist;
oList = FXCollections.observableArrayList((JsonObject[])myItems.toArray())
idListView.setItems(oList);
Not working for me. What can I do diffently?
/regards
//lg
I followed this advise "You may convert the json data to map and follow Example 12-12 Adding Map Data to the Table. – Uluk Biy Jun 5 at 9:05"
Related
I have a URL with a large number of entries that I want to persist into the MySQL database so that I can use my rest API to call on them. I have set up the whole structure as if im ready to use my own api, with entities, dtos, controllers, resources etc.
What I cannot figure out is, how do I persist json from the external api call into my database? Do I need to convert the json to entities before i persist them, or can I parse them directly into my database? And how would I go about persisting such a large json string with so many entries?
I've made an endpoint that calls the api, so that I can update the database on call, but I don't really know what to do next here
#PostMapping(value = "/popDB")
private itemEntity getItemObject() throws IOException {
URL url = new URL("api url string");
InputStream inputStream = url.openConnection().getInputStream();
ObjectMapper mapper = new ObjectMapper();
Map<String, Object> jsonMap = mapper.readValue(inputStream, Map.class);
articleService.save((ItemEntity) jsonMap);
return (ItemEntity) jsonMap;
}
I'm using Flink to process some JSON-format data coming from some Data Source.
For now, my process is quite simple: extract each element from the JSON-format data and print them into log file.
Here is my piece of code:
// create proper deserializer to deserializer the JSON-format data into ObjectNode
PravegaDeserializationSchema<ObjectNode> adapter = new PravegaDeserializationSchema<>(ObjectNode.class, new JavaSerializer<>());
// create connector to receive data from Pravega
FlinkPravegaReader<ObjectNode> source = FlinkPravegaReader.<ObjectNode>builder()
.withPravegaConfig(pravegaConfig)
.forStream(stream)
.withDeserializationSchema(adapter)
.build();
final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
DataStream<ObjectNode> dataStream = env.addSource(source).name("Pravega Stream");
dataStream.???.print();
Saying that the data coming from Pravega is like this: {"name":"titi", "age":18}
As I said, for now I simply need to extract name and age and print them.
So how could I do this?
As my understanding, I need to make some customized codes at ???. I might need to create a custom POJO class which contains ObjectNode. But I don't know how. I've read the official doc of Flink and also tried to google about how to create a custom POJO for Flink but I can't still figure out clearly.
Could you please show me an example?
Why don't You simply use something more meaningful instead of JavaSerializer? Perhaps something from here.
You could then create a POJO with the fields you want to use and simply deserialize JSON data to Your POJO instead of ObjectNode
Also, if there is some specific reason that You need to have ObjectNode on deserialization then You can simply do something like :
//I assume You have created the class named MyPojo
dataStream.map(new MapFunction<ObjectNode, MyPojo>() {
ObjectMapper mapper = new ObjectMapper();
#Override
public MyPojo map(final ObjectNode value) throws Exception {
mapper.readValue(value.asText(), MyPojo.class)
}
})
I want to save a JSON object as a Document in Couchbase. The id of this document is supposed to be retrieved from this JSON object and the value is supposed to be this JSON object itself. Since this JSON is too complex, I haven't mapped it directly to any POJO class, but I have created a Simple POJO, which has two fields as shown below
#Document
public class SimplePojo{
#Id
private String id;
#Field()
private String complexJsonString;//the JSON string is stored in this variable
}
I also have a SimplePojoRepository as shown below
#Component
public interface SimplePojoRepository extends CouchbaseRepository<SimplePojo, String>{
}
Now, I am setting the id and complexJsonString manually before calling the save method:-
SimplePojo myObj= new SimplePojo();
myObj.setId(myKey);
myObj.setComplexJsonString(jsonString);
simplePojoRepository.save(myObj);
This is working fine, but it is saving the Document in below format
myKey: {
complexJsonString : {//the original json Object here}
}
but I don't want this, I want to save it like this:-
myKey : {//the original json Object here}
So, to make it clear, I don't want to save my JSON object as a value of complexJsonString but rather, directly as a value of the myKey . Can someone please guide me on how to achieve this?
If you want to store the complexJsonString as a nested entity within your main object, you have to transform it in a Pojo:
myObj.setSomeEntity(new SomeEntity())
You can easily transform your JSON-encoded String to object using jackson's ObjectMapper:
ObjectMapper mapper = new ObjectMapper();
mapper.readValue( jsonString, SomeEntity.class);
However, if you don't have control on the structure of this json, you will need to use the standard Java SDK instead of the Spring Data One:
JsonObject obj = JsonObject.create().put(this.documentTypeName, this.documentValue)
.put("attrNam1", "attrValue1")
.put("attrNam2", "attrValue2")
JsonDocument doc = JsonDocument.create(session.getId(), maxExpirationTime, obj);
bucket.upsert(doc)
In the case above, you will need to parse your JSON-encoded string using some lib (ex: gson/jackson) and then convert it to a couchbase JsonDocument.
Lastly, you could also leave your code as it is and use the N1QL function DECODE_JSON() whenever you need to access some property of this json string.
ex:
SELECT
i.itemName as itemName,
SUM(i.quantity) AS totalQuantity
FROM sessionstore s
UNNEST DECODE_JSON(s.sessionCart).shoppingCart.items i
WHERE s.sessionCart IS NOT MISSING
GROUP BY i.itemName
ORDER BY SUM(i.quantity) DESC
LIMIT 10
I wanted to generate a test program to execute against our client tenants to verify we could handle all the data our new Microsoft graph app collects. My plan was to serialize the data using
XmlSerializer serializer = new XmlSerializer(typeof(List<T>));
It failed on the first entity I tried, Microsoft.Graph.Domain ( in this case with the error
Cannot serialize member Microsoft.Graph.Entity.AdditionalData of type ... because it is an interface.
A search on stack overflow found suggestions to decorate the problematic class property with XmlIgnore so XmlSerializer will ignore it, others recommended implementing a new IXmlSerializer. One post seemed to propose using serializing to XAML.
Open to a better way to collect real customer data which I can import into my unit tests? As a developer I do not have direct access to customer accounts.
Does anyone have other suggestions on how to serialize Microsoft Graph Entities.
I replaced my XmlSerializer with a Json one.
public void SerializeObjectsToJson<T>(List<T> serializableObjects)
{
var jsonStr = JsonConvert.SerializeObject(serializableObjects);
}
public List<T> DeSerializeObjectsFromXml<T>()
{
TextReader textReader = new StreamReader(fqpathname, Encoding.UTF8);
var jsonStr = textReader.ReadToEnd();
data = JsonConvert.DeserializeObject<List<T>>(jsonStr);
}
This all seems to work with Domain, User, SubscribedSkus, Organization, etc.
I am using Xamarin Forms with Newtonsoft.JSON and Xam.Plugin.Settings plugins to save IDevice object as JSON to use it later.
First page:
private async void SelectBluetoothDevice(object sender, SelectedItemChangedEventArgs e)
{
string device = JsonConvert.SerializeObject((IDevice) e.SelectedItem);
AppSettings.AddOrUpdateValue("device", device);
await Navigation.PopAsync();
}
Here I simply make selected item to JSON string and save it. It works like it should be.
But the problem im facing comes whenever I try to deserialize from saved string.
string device = AppSettings.GetValueOrDefault("device", "");
if (!device.Equals(""))
{
Debug.WriteLine(device);
// This line produces error
IDevice dev = JsonConvert.DeserializeObject<IDevice>(device);
settingsDeviceName.Text = dev.Name;
}
Newtonsoft.Json.JsonSerializationException: Could not create an
instance of type Plugin.BLE.Abstractions.Contracts.IDevice. Type is an
interface or abstract class and cannot be instantiated. Path
'BluetoothDevice', line 1, position 19.
So I understand that IDevice is interface and my JSON string cant be deserialized nothing but into object. Any good ideas how to workaround it? Thanks!
This line JsonConvert.DeserializeObject<IDevice>(device); basically does this:
Read the JSON in device
Try to create the type of object you want to deserialize to, in this case, IDevice
Return you the new object with all the properties filled
The problem is with step 2. You can't create an instance of an interface. So you need to deserialize to a concrete object that implements IDevice.