Gson deserializes with empty fields

问题

The result variable contains corrected parsed JSON. But after deserialization List contains correct amount of items but all of them are empty. How to fix it?

Gson gson = new Gson();
List<UnitView> unitViews = new ArrayList<UnitView>();
// https://stackoverflow.com/questions/5554217/google-gson-deserialize-listclass-object-generic-type
Type typeToken = new TypeToken<List<UnitView>>() { }.getType();
unitViews = gson.fromJson(result,typeToken);

Even if I do like

UnitView[] unitViews = gson.fromJson(result, UnitView[].class);

The fields of items are empty as well.

UnitView

public class UnitView implements Serializable {

    public String id ;

    public String name ;

    public String description ;

    public String deviceTypeName ;


    public String categoryID ;

    public String lastOnline ;

    public String latitude ;

    public String longitude ;

    public String atTime ;

    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public String getDescription() {
        return description;
    }

    public String getDeviceTypeName() {
        return deviceTypeName;
    }

    public String getCategoryID() {
        return categoryID;
    }

    public String getLastOnline() {
        return lastOnline;
    }

    public String getLatitude() {
        return latitude;
    }

    public String getLongitude() {
        return longitude;
    }

    public String getAtTime() {
        return atTime;
    }

    public void setId(String id) {
        this.id = id;
    }

    public void setName(String name) {
        this.name = name;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public void setDeviceTypeName(String deviceTypeName) {
        this.deviceTypeName = deviceTypeName;
    }

    public void setCategoryID(String categoryID) {
        this.categoryID = categoryID;
    }

    public void setLastOnline(String lastOnline) {
        this.lastOnline = lastOnline;
    }

    public void setLatitude(String latitude) {
        this.latitude = latitude;
    }

    public void setLongitude(String longitude) {
        this.longitude = longitude;
    }

    public void setAtTime(String atTime) {
        this.atTime = atTime;
    }
}

JSON DATA

[{"ID":"294","Name":"Foton Tunland  № F110","Description":null,"DeviceTypeName":"Техника ТО","CategoryID":"18","LastOnline":"19.12.2017 20:38:04","Latitude":"11,40119","Longitude":"11,42403","AtTime":"19.12.2017 20:38:04"},{"ID":"295","Name":"DML LP1200  № 9793","Description":null,"DeviceTypeName":"Буровой станок дизельный","CategoryID":"15","LastOnline":null,"Latitude":null,"Longitude":null,"AtTime":null}]

回答1:

Ok , the problem is that the parser is case-sensitive, you can change the name of your attributes to match the name of the json value of you could use the SerializedName annotation like this:

@SerializedName("ID")
public String id ;
@SerializedName("Name")
    public String name ;
@SerializedName("Description")
    public String description;
...

    public String ID ;
    public String Name ;
    public String Description ;
...

回答2:

I think you're having this problem because of null values in your json. Check it. Source

来源：https://stackoverflow.com/questions/47898640/gson-deserializes-with-empty-fields

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java

android

gson

json-deserialization