GSON Expected BEGIN_ARRAY but was BEGIN_OBJECT - java

I'm getting this error when I receive only one single item in a list. I'm using Jersey in the server side REST Web service, I only get the error when the List returned one single element and when it has 0 elements I get java.lang.NullPointerException But when it has more than one it works perfectly, and this is how I'm doing it :
#GET
#Path("getproject")
#Produces(MediaType.APPLICATION_JSON)
public List<Project> getPagedProjects(
#QueryParam("offset") int offset,
#QueryParam("limit") int limit,
#QueryParam("searchKey") String searchKey) throws Exception {
System.out.println("Returning Paged Project ");
return projectService.getPagedProjects(offset, limit, searchKey);
}
Why doesn't Jersey send a list that contains one single item? It is a bug in jersey?
Is there a way to make it always serialize as an array?
This is my JSON data when the web service returns 0 element:
null
And This is my JSON data when web service returns 1 element :
{
"project": {
"abbreviation": "abc",
"customer": "customer1",
"description": "description3",
"icon": "iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAAN4UlEQVR42u2ZeXBUx53Hx8FgSAIWMiB0jO7RLRkwbFxxnC1ntyp/JXbh9TrmirEDOpA4JQQ6kdCBDiQOU65UjNdO2djYGLCzKRJjY841SJoZzaEZaTSjc0b3hST0JCH5u79fa54YCZLUZteurQpTfKq7X/f0+35//et+b4RC8fDz8PPw8/Dz8PMP/ykoKFBkZmY+evLkyR9//PHHr545c2azC6/9BUQ/jd/w4Ycf/uLNN9+M3r179w8AKNzd3b878eXl5QoSoXjnnXd+ZjAYmjo7Oye6uromme7u7m+coKenR+YbF3jcWHt7+2B9fX3r1atXP3777befW7du3aOpqanfjYGysjJFY2Oj4uzZszt6e3sxOjoqGBu/i7sTE8QkJia/EdC/aeRr3D9+9y7Gx8cxPDyM2tpaO821JysrayHP/Z0YuH37tuLcuXO7+vr6vpEN9LZa4DBcQ5vxGjpqrqOz5ga6TIT5Brpd6K27hZGBboyNjU2bdzgcdy5duvS7N954I4Ru8ciWLVu+XQMDAwO8AjvZAEe+v7kG2pyfQLvTG7rdSuj3+MKQ4gdjqr+gJtUPpr2+MKcoUZushP10CkZHhoV4SZIENNeEXq+vvnDhwqFTp05tfPfdd1+gNP3l/5a33nrrudLS0sePHj2qyMvLu9/A+N0J9JmvonE/CUtdBHvWUtgLvGEv9Ye9PHCKEj/Y871gz1wCe/IP0fnbtZAG+yCRgZGREdy5c0fAKUVpOUkrIrW0tAw3NzcPNzU1DTGUtoKGhgaBzWYTWK3WIdpPAovFIqirqxNQeg5TUPo+++yzQ+vXr3/0yJEjD1qBcYwO38bA1++g90IG+r7MRd+1QvTdLEFfVRn6Kg+j7+ti9F7JR+/FAzQmG0OWa9PiZQMsfmhoSDA4OCigVAXdC/39/bxCbG76cOCDgg4E0CGCjo4O0MGAtrY2AQUAdrsdra2tAjosqnJycpbyKggDNOE9A5TLY2Pj4JVgeJPOwHmdU43HjRLS6NgDxcui/y+E0wqCVlCUZKA6Pz/fY4aBTz75ZIdsQJxCVPLJwsyuy5tVzvm/FnlZPCOLlw3I4mUDLF42MDvqsgGGDdCz654BmlgY4HyVhbEgnpQFsWguuc3XnZtU3FjOd44ei2LhLJZvykK5zuMo70U/X+M+bsvCKfdFm8WzaLPZLIRynfYHjEaj6Je5cuXKzBWgSYUBfjDJpwgLoQ0khIpjlW7Mbb7OJnhyvrEccdp0QhhHncfyTVkQpw1HkzafEMwmeB7ul9NGp9Px80OM50hXVFSANrOYjzYvbt68KYzQpp82MGMF2AC9FmynJZ2cfYrIdYaF8jXXHJdLOU1cc9013zldZue7a86zSTlt2IQMrwQLl2ED96UQ3UAY4NcHWeBf4kEni2ueP0j87M06Y8O2dwgcbR2wOziF2tBqd6Cl1Y7mFjuamjndWtDohNtXrl6vziso9ig/emKmAZp4UhYoR9s10rNPFtfTZfYp8zcj39FJEaco27RoMFyETfsH2NTnYdUwn8Kq/RT1DLUtdN1SdQ6WyrOCa+fLrJ8XRT9/rXShlzBAk/ML3XaaeFKOLIvhvGMR3GYR3JbF8nLzcsqiuU/euCyWc5dTg+vyxmxra0dHZxds1lqYbpyC+VQsDAXPQLc3DLo9wdDvVUGfFgFdZjQMB1fBWLCG+ldDn7sC+uyYqb4UFbSJ3ner4xZ1VOW4nxcGSDgbSKIlnZRToaenl25ah86ubtweHBYRM1G7p7cf/QODtJzNqLNY0dvXT9f6YK6tQ0Njk6i3d3TRpjVSGjjQ1d0jlr1apyeDzWgyfgHd71+DencQtBuWQP1v7qhcuxhVa92p/oSg8kV3VHH9pSWinG47qXh+0V3184/2aNLddMIACVd89NFHSRTVSRFRoqeLNpXlKhymz+EwX4Sj9gviS7RZLqGt/is4rFO02S4L7PWXYLd8ida6L9BC45tr/oxm45/QpPsjGivPoP7yCZg/SKBIrkL15uXQvLwM6r8LD1SsdRtXvzi3uyp78Z+EARKuOH36dBIt9SSnQ09PJ6x/PggDLaU+OYSWNgyGfREwpkXBmBEDY9YKGA+sQk3uatQc/CdiDYw5q2EkcYbMJ2FIpxTYHwl9aji9CIZAtz0A1XG+0P7aE5pXSPwrntOo/w4qXnQf17w8r6Mid/F7wgAJFwYohyc4hzvsFtSc+DmqN3nTMiud+EC7/h6a+/B24vPXoXnU651scELfm0Luc23P6qPxFS8tGdNsmG+/ledWLAyQcAX9LEyiM3eim3Lf0aiFvuhpVLGgTX4UOX9RVrJ4Z1u9wRdVbIzqDPdVbfSdMVZNba5zWbFuai6mar1yqp/7Nk318VyuY+Xv8nW5rXZ+v/Jlj1H15gUtX+e77RAGSLgwQKfKBG+6ZvNXtPNXQcPiXg2EdnOQKDW/DqD6VFvj2nbWNa8GTI0n1C5t7lNv8hdtjbNPtHmMs6521me3Z49lKn7lOare8v2G64fc/n36J+UHH3yQSOUEnzoNmrPQZ0Sj+nU6sv6nvBY8jeZbQUWr5z1aFf8D49Vit58JA/ROo6BfTYlUTrTTOW258Radt+Go3hIm0DpxrT+Y0Jn8JhSab4HKjcrRyqQfVlwucVshDNCLkzBA5QQ/1msvlkK3KxTq35CorRGojo0UpZpFxnI7Apqt4dNthsdqtoSLcVrqq+KbbZ1q83Vua6fbYfRdaseGC9RbeSy146gdR31bQ0SpjXdp81jup3tVbvYbq9i98Ksvy9yUwgC9HQoD9EY50UpPzZrz+1C9IxwVr5OouChUJ0RDQyYq2BC346NRRaIq5TZR+TobplWLjSKRkah8LUQI1sWR+dgwMqCCjgTpt5GIeEq1eHrybqfjeTsJ3xZER60Khp2h0O8MgSYxELodITBQELnUJAZBv4P7wqgMhyaeDOxf9J8X3ljsJgzQY1/x/vvvJ1I50dLSBD094nU7oqFNeJLEuxAfQyKIuBgSGi3QTRMFPRkxxBMJkTAmhKMmkUgKg4lEmkiIeVcIancTe1SoTVahLoUJRt1eIvUetfuc7FcJzPuYEJgEZCTZ725F1qJ3Pz2xeIEwQO/iwgCVE42NFuh+9zJ0iSR020roElaQaOZJ6Jk4J7ExMJARI61GTUIUTImRMCdFoHZ7OOooUnUUPQs9xOpJaD0JtZJIa2oQbPuI/YGwpQWiIZ3ICLhHJpE1hc2JNStQUJ8VRATDkqWCKV05UZH7+OET/7FkjjBgMpkU7733XqLZXDthq9Oi+tgvaKnpBSqBnqxM/EoSuxJGhszU0GqYtsWQ4CgSHEmCI1C/KxzWPWGwJYfClhKCBnoxa6QoNu4PQhOJbc4gSGBLlj9ashk/tB4gchhftOZO0XJQxg/NTpoO+gsac8lcbiAsB7wnK/IeT7dnLVLcZ6C+5jp0Rf8qhGu30GtBHL0yJDwlhBson2uTYmCh9KrjSFNe2vaEoyGFhZPYvUFoSQtGC0W2Oc0PdhLrILGOA76wZ/ugPVeJ9jwl2g56E15oz/dGewHV870E7YU+aCv0hj3fEw4qHdS2Ey00rrWQDBb6oaXAH9Y8r7Fb+W6xhly3WQZq6ybqqj+HLucZyuHVlNcrKNKrSPRKijRHPBLW3VFoSI4kQtFI+duapoI9I4jwR1uWHzpz/NFJEezM9UF3vg96CggS013oid4iL/QVc7kcPUUe6C1Zjt5SqhcvQ0+JB3qo3k3XOoo90FniSZCpYi84DnmirYjMFSnhKPKFrdB79Ov8J16sOrj0fgO1t87QQ+xpEruGIvwULDtXoX73CopwDEU4Cs37wtGaHgpHpgrt2UEkOADdtLw9+X7oLfBDP0VqgG5yu1iJ2yVKDJb6YPAw442hMq8pyj2J5YQHBo8wy3BbsBQDRH/5MvQRvWUe6C7zRNdhL3SWeqOjhFaM5rQd8hq6nrfs2Ru5HorpTUwGktiA8dJJGPf/CJZdq1G/5ynK55VoTI1BC71d2jPC0J4VQqKDSXQgiQ5AHy3pwCF/EuyPwRJ/DJX6Y/iwP+6U+WOknDjiD4k56kf4QjrG+BDeGDnmhZHjywkP3Dm+DMOCpRg8thS3iYGjZISM9ZLZHjLeRYHopIBYCpWdFzO9Ij7P9FIo+M9zly9fZgNxJtoD2j8chyl1DazJT9FGXEkRj6aIR1DEQ9FxQIWu3CD05AWS8AAMFJLoogAMlQRguDQAI4cDIZUFYbQ8GGNHVEQIxo+GTnGM6sdURBDGjwcQfhg7riS8MXrcExKZGCEDd8gAM3RsCQaP8orwalC6lVF60SqyAWNOkPmjXdE+Z5IjFYpHHnmE/8Y7JyUl5blz5z81/fH3x6Qvdv5Y+q9tMdLNpCjp1vYIqXJnuKTeFSpp94RIumSVpE9RSYa9wVJNarBk2qeSzPtVUm1aiFSXHirVZ4RJ1swIyZYZKTVkRUkN2TFSoyCa6tyOIMIkW3aIZM0OluqzA4kAyZLlL9Vl+UrmTF/JlKmUTBlKyUgY0pWSPt1Xqk7zk7T7/aVbe4PunI6NPLlS5fME61bMmTPne4899pj7ggULVq9Zs+bVtS+8sO+lf3k67VfPhKczrzA/CUtf58L6Z++xQeanU2z8abhgE/PPMhEudSZMsJER3wkVbHCy/tmZrJsmLP35H4XuUXos+eW8x+ZHLJg/f6H4E/u8efPmzJ079/u0GnyBWeQs/18yd+68hRT0+aT7ew//g/Dh5x/989/YnyApxuVsjAAAAABJRU5ErkJggg==",
"name": "projectname3",
"plannedEndDate": "2012-05-23T00:00:00+01:00",
"plannedStartDate": "2012-05-23T00:00:00+01:00",
"projectStatus": {
"name": "In Progress"
},
"realEndDate": "2012-05-23T00:00:00+01:00",
"realStartDate": "2012-05-23T00:00:00+01:00"
}
}
And This is my JSON data when web service returns more than 1 element :
{
"project": [
{
"abbreviation": "abd",
"customer": "customer1",
"description": "description1",
"icon": "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",
"name": "projectname1",
"plannedEndDate": "2012-05-25T00:00:00+01:00",
"plannedStartDate": "2012-05-23T00:00:00+01:00",
"projectStatus": {
"name": "Opened"
},
"realEndDate": "2012-05-25T00:00:00+01:00",
"realStartDate": "2012-05-23T00:00:00+01:00"
},
{
"abbreviation": "bd",
"customer": "customer1",
"description": "description2",
"icon": "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",
"name": "projectname2",
"plannedEndDate": "2012-05-23T00:00:00+01:00",
"plannedStartDate": "2012-05-23T00:00:00+01:00",
"projectStatus": {
"name": "Closed"
},
"realEndDate": "2012-05-23T00:00:00+01:00",
"realStartDate": "2012-05-23T00:00:00+01:00"
},
{
"abbreviation": "abc",
"customer": "customer1",
"description": "description3",
"icon": "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",
"name": "projectname3",
"plannedEndDate": "2012-05-23T00:00:00+01:00",
"plannedStartDate": "2012-05-23T00:00:00+01:00",
"projectStatus": {
"name": "In Progress"
},
"realEndDate": "2012-05-23T00:00:00+01:00",
"realStartDate": "2012-05-23T00:00:00+01:00"
}
]
}
And in android side I deserialize the JSON response like this :
Gson gson = new Gson();
final ProjectContainer container = gson.fromJson(resultat, ProjectContainer.class);
final ListView lv = (ListView) findViewById(R.id.list);
adaptateur = new ProjectAdapter(ProjectActivity.this, R.layout.ligne_project, container);
lv.setAdapter(adaptateur);
This is my ProjectContainer class :
public class ProjectContainer {
#SerializedName("project")
List<Project> projects ;
public List<Project> getProjects() {
return projects;
}
public void setProjects(List<Project> projects) {
this.projects = projects;
}
}
I would greatly appreciate your help to solve this problem. Thanks in advance

Your issue results really weird for me... it seems that there must be some problem with Jersey's JSON serialization of single element arrays... if you Google "Jersey JSON single element arrays" you'll find the same issue, like here or here. I don't know too much about Jersey, so I can't help you with that...
That said, I can suggest a workaround using manually parsing in Gson, to adapt your parsing to the 2 different responses (object or array). You could do something like this:
//manually parsing until get the "project" element...
JsonParser parser = new JsonParser();
JsonObject rootObejct = parser.parse(yourJsonString).getAsJsonObject();
JsonElement projectElement = rootObejct.get("project");
Gson gson = new Gson();
List<Project> projectList = new ArrayList<>();
//Check if "project" element is an array or an object and parse accordingly...
if (projectElement.isJsonObject()) {
//The returned list has only 1 element
Project project = gson.fromJson(projectElement, Project.class);
projectList.add(project);
}
else if (projectElement.isJsonArray()) {
//The returned list has >1 elements
Type projectListType = new TypeToken<List<Project>>() {}.getType();
projectList = gson.fromJson(projectElement, projectListType);
}
//Now you have a List<Project> projectList with one or many Project elements,
//depending on the response...
Note that you don't need your class ProjectContainer.
Something like this should work for you, although obviously the best thing would be fix the serialization issue!

Basically, your web service is broken in terms of how it's replying. If there's only one object for project it's returning only an object instead of an array.
MikO's answer solves the problem but another approach is encapsulating that logic in a custom deserializer:
class MyDeserializer implements JsonDeserializer<ProjectContainer> {
#Override
public ProjectContainer deserialize(JsonElement je, Type type, JsonDeserializationContext jdc) throws JsonParseException {
JsonObject jo = je.getAsJsonObject().getAsJsonObject("project");
if (jo.isJsonArray()) {
return new Gson().fromJson(je, ProjectContainer.class);
} else {
Project p = jdc.deserialize(jo, Project.class);
List<Project> pList = new ArrayList<Project>(1);
pList.add(p);
ProjectContainer pc = new ProjectContainer();
pc.setProjects(pList);
return pc;
}
}
}
Then you can use:
Gson gson = new GsonBuilder()
.registerTypeAdapter(ProjectContainer.class, new MyDeserializer())
.build();
ProjectContainer pContainer = gson.fromJson(myJson, ProjectContainer.class);

I ended up using Jackson library instead of gson to parse the json response. It automatically converts object into ArrayList. It is pretty much similar to gson in terms of ease of use. Hope it helps!

Related

Comparing two JSON files using java

I have two JSON files, called "pickevent1" and "pickevent2". I have to compare if both files are matching; if they don't match, I need to know where they don't match.
pickevent1
{
"pickEventActivities": [{
"orderId": "215",
"lineNbr": 0,
"pick": "EACH",
"activations": [{
"activationType": "Si",
"activationValue": "31"
}]
}]
}
pickevent2
{
"pickEventActivities": [{
"orderId": "115",
"lineNbr": 1,
"pick": "Hello",
"activations": [{
"activationType": "Bi",
"activationValue": "3"
}]
}]
}
I created a pick event POJO class:
#JsonRootName(value = "pickEventActivities")
#Data
#JsonPropertyOrder({ "orderId", "lineNbr", "pick"})
class PickEvent {
String orderId;
String lineNbr;
String pick;
List<Activation> activations;
}
and a Activation POJO class:
#Data
#JsonPropertyOrder({ "activationType", "activationValue"})
public class Activation {
String activationType;
String activationValue;
}
To make sure it works, I created a test class:
public void compareJson() throws Exception {
final ObjectMapper objectMapper = new ObjectMapper();
objectMapper.configure(FAIL_ON_UNKNOWN_PROPERTIES, false);
objectMapper.configure(ACCEPT_SINGLE_VALUE_AS_ARRAY, true);
PickEvent result1 = objectMapper.readValue(new File("src/../pickevent1.json"), PickEvent.class);
PickEvent result2 = objectMapper.readValue(new File("src/../pickevent2.json"), PickEvent.class);
assertEquals(result1, result2);
}
But when I am doing assertSame(result1,result2) its giving me null for json values:
Exception in thread "main" java.lang.AssertionError: expected same:<PickEvent(orderId=null, lineNbr=null, pick=null, activations=null)> was not:<PickEvent(orderId=null, lineNbr=null, pick=null, activations=null)>
at org.junit.Assert.fail(Assert.java:88)
at org.junit.Assert.failNotSame(Assert.java:828)
at org.junit.Assert.assertSame(Assert.java:771)
at org.junit.Assert.assertSame(Assert.java:782)
at JsonDiff.PickEventDiff.comparejson(PickEventDiff.java:26)
at JsonDiff.PickEventDiff.main(PickEventDiff.java:32)
It should give me an assertion error, but the test succeeds.
It should give me an assertion error, but the test succeeds.
Because you use objectMapper.configure(FAIL_ON_UNKNOWN_PROPERTIES, false);. In fact, an exception occurred during the parsing process.
Try:
public void compareJson() throws Exception {
final ObjectMapper objectMapper = new ObjectMapper();
Wrapper wrapper = objectMapper.readValue(new File(""), Wrapper.class);
Wrapper wrapper2 = objectMapper.readValue(new File(""), Wrapper.class);
System.out.println(wrapper.equals(wrapper2));
}
#Data
static class Wrapper {
List<PickEvent> pickEventActivities;
}
You are trying to read a PickEvent Object but you're actually sending a list there.
Please change your json to
{
"pickEventActivities": {
"orderId": "115",
"lineNbr": 1,
"pick": "Hello",
"activations": [{
"activationType": "Bi",
"activationValue": "3"
}]
}
}
or try changing your code to
List<PickEvent> list1 = objectMapper.readValue(new File("src/../pickevent1.json"), new ParameterizedTypeReference<PickEvent>(){});
Here is my github repo for Intellij Idea plugin.
Basically JSON comparator implemented in java. It compares JSON by fields, values and objects in array

Json Parsing: How to fetch "body" data inside "body array" using Gson (or better in other java library or notation supported)?

My Rest API is returning the following response, in which only the inner list is required, all data shall be discarded:
{
"meta": [],
"links": [],
"body": [
{
"meta": [],
"links": [],
"body": {
"field1": "value1",
"fieldn": "valuen"
} // <-----
},
{
"meta": [],
"links": [],
"body": {
"field1": "value1",
"fieldn": "valuen"
} // <-----
}
]
}
Is there any way in Gson or another other java library to fetch an array of the body or a straightforward way of doing that? Or maybe even using standard of java 8?
Or, should I use a standard iterator as follows:
//Old way to do this
JSONArray BodyArr = (JSONArray) jsonObject.get("Body");
Iterator<JSONObject> itBody = BodyArr.iterator();
int teller = 0;
while (itBody.hasNext()) {
JSONObject bodyObj = itBody.next();
JSONObject body = (JSONObject) bodyObj.get("Body");
}
Also in mysql we have way to do that using notation ($.body.body[] etc.). Is there any notational way to fetch the object
I think we have a nicely written article on this.
Json object iteration
If you have a class that represents an object in the array, then you can deserialize the JSONArray to an array of that class using public <T> T fromJson​(JsonElement json, java.lang.Class<T> classOfT) throws JsonSyntaxException on the Gson class:
class BodyItem {
public String[] meta;
public String[] links;
public String field1;
public String fieldn;
}
public BodyItem[] getBodyItems(final Gson gson, final JsonObject jsonObject) {
final JsonElement body = jsonObject.get("body");
return gson.fromJson(body, BodyItem[].class);
}
public static void main(final String[] args) {
final String response = "<your REST API JSON response>";
final Gson gson = new Gson();
final JsonObject jsonObject = gson.fromJson(response, JsonObject.class);
final BodyItem[] bodyItems = getBodyItems(gson, jsonObject);
}
If you want a more notational way of accessing fields in Gson objects, you can use JsonObject's convenience accessors:
JsonArray getAsJsonArray​(java.lang.String memberName)
JsonObject getAsJsonObject​(java.lang.String memberName)
JsonPrimitive getAsJsonPrimitive(java.lang.String memberName)
And then with a JsonArray, you can iterate with for (final JsonElement element : jsonArray) or .forEach, and you can get JsonElements with the JsonElement get(int i) accessor.
So, say you had your original JsonObject response and wanted to get the value of body.field1 in the second element of the body list, you might do:
String value = jsonObject
.getAsJsonArray("body")
.get(1)
.getAsJsonObject()
.getAsJsonObject("body")
.getAsJsonObject("field1");

Parsing JSON from API with GSON [duplicate]

This question already has answers here:
Why does Gson fromJson throw a JsonSyntaxException: Expected BEGIN_OBJECT but was BEGIN_ARRAY?
(2 answers)
Closed 3 years ago.
I'm make an API call with retrofit, the problem is the JSON I get from the call. Normally it was a simple Json with an array in it.
[
{
"herbID": 1,
"nameTrival": "Baldrian",
"nameWissenschaft": "Valeriana officinalis",
....
},
{
"herbID": 2,
"nameTrival": "Ringelblume",
"nameWissenschaft": "Calendula officinalis",
....
},
....
]
The new call looks like this
[
[
{
"nameTrival": "Baldrian",
"nameWissenschaft": "Valeriana officinalis",
"hoeheFrom": 20,
"hoeheTo": 200,
"familie": "Baldriangewaechse",
"pflanzentype": "Staude",
"auffaelligkeiten": "Je nach Standort sind die Fiederblätter schmäler oder breiter sowie dunkel- oder hellgrün, oft auch unterschiedlich geformt."
}
],
[
{
"standort": "Ufer"
},
{
"standort": "Graben"
},
{
"standort": "Wiesen"
},
{
"standort": "Waldrand"
}
],
[
{
"gebiet": "Nordeuropa"
},
{
"gebiet": "Südeuropa"
},
{
"gebiet": "Westeuropa"
},
{
"gebiet": "Osteuropa"
},
{
"gebiet": "Südosteuropa"
},
{
"gebiet": "Mitteleuropa"
},
{
"gebiet": "Südwesteuropa"
},
{
"gebiet": "Nordosteuoropa"
},
{
"gebiet": "Nordwesteuropa"
}
],
{
"fieldCount": 0,
"affectedRows": 0,
"insertId": 0,
"serverStatus": 34,
"warningCount": 0,
"message": "",
"protocol41": true,
"changedRows": 0
}
]
I parsed the first Json with the following code
Call<List<Herb>> call = service.getAllHerbs();
call.enqueue(new Callback<List<Herb>>() {
#Override
public void onResponse(Call<List<Herb>> call, Response<List<Herb>> response) {
herbList = response.body();
loadDataList(herbList);
}
#Override
public void onFailure(Call<List<Herb>> call, Throwable t) {
Toast.makeText(PlantListActivity.this, "Unable to load herbs\nCheck your internet connection", Toast.LENGTH_LONG).show();
}
});
The new class looks like this
public class Herb{
ArrayList<Botanical> botanical;
ArrayList<Location> locations;
ArrayList<Area> areas;
public ArrayList<Botanical> getBotanical() {
return botanical;
}
public ArrayList<Location> getLocations() {
return locations;
}
public ArrayList<Area> getAreas() {
return areas;
}
}
With the new Json and the class it always fail with the error "java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2 path $"
Didn't I tell gson that the following is an array, after I declare them as an ArrayList? What is wrong with my class?
EDIT:
The difference between the possible duplicate and my question is, that the other one has arrays with names. My json arrays doesn't have one, that's why I have a hard time parsing them.
If you want to handle response with type Herb class, then you need to modify service response like
Rather than
[{},{},{}] // this is much difficult to handle
Try this which has to be done at server end
{
"botanical":[],
"area" : [],
"location" : []
}
Then call will be Call<Herb> someMethod();
If change not possible
then handle it as JsonArray
Call<JsonArray> someMethod();
By this you can handle existing response and fetching value key and parse as per requirement. But this is not recommended because it's difficult to maintain if future change and require lot of change
The problem is you're telling Gson you have an object of your type. You don't. You have an array of objects of your type. You can't just try and cast the result like that and expect it to magically work ;)
The User guide for Gson Explains how to deal with this
Your new response is very bad. It's impossible to parse that kind of JSON.
It represents array of different objects (different type). So, GSON can do nothing, you have to create a class that is equivalent to the entire response.
Your first JSON response is fine.

apply gson UPPER_CAMEL_CASE for specific sub-json

I have these messages arriving from SQS:
{
"eventID": "zzz",
"eventName": "MODIFY",
"eventVersion": "1.1",
"eventSource": "aws:dynamodb",
"awsRegion": "us-east-1",
"dynamodb": {
"ApproximateCreationDateTime": 1521976320,
"Keys": {
"key_1": {
"S": "yyy"
},
"key_2": {
"S": "xxx"
}
},
"SequenceNumber": "123",
"SizeBytes": 321,
"StreamViewType": "KEYS_ONLY"
},
"eventSourceARN": "arn:aws:dynamodb:us-east-1:eventSourceARN",
"itemType": "myItem"
}
I want to use gson library to convert this json string into a Record object (com.amazonaws.services.dynamodbv2.model.Record) which contains a StreamRecord object (com.amazonaws.services.dynamodbv2.model.StreamRecord) that represents the dynamodb sub json.
problem is that the inner fields of the dynamodb object are PascalCase while the other fields are normal camelCase.
This code:
Gson gson = new GsonBuilder()
//.setFieldNamingPolicy(FieldNamingPolicy.UPPER_CAMEL_CASE)
.create();
String json = <the json from the example above>
Record record = gson.fromJson(json, Record.class);
log.info("record="+record.toString());
StreamRecord dynamodb = record.getDynamodb();
log.info("dynamodb="+dynamodb.toString());
Map<String, AttributeValue> keys = dynamodb.getKeys();
log.info("keys="+keys.toString());
prints this log (UPPER_CAMEL_CASE commented out) :
record={EventID: zzz,EventName: MODIFY,EventVersion: 1.1,EventSource: aws:dynamodb,AwsRegion: us-east-1,Dynamodb: {},}
and then throws Null Pointer exception because the dynamoDb object is empty - because my json string is UPPER_CAMEL_CASE, while in the object its normal camelCase.
I want to apply FieldNamingPolicy.UPPER_CAMEL_CASE only for the dynamodb sub json.
perhaps somehow using FieldNamingStrategy ?
The json is given and I cannot change its schema.
I also can't change the fact that I get it as string.
see AWS API:
https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_streams_Record.html
https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_streams_StreamRecord.html
You seem to want the following naming strategy:
private static final Gson gson = new GsonBuilder()
.setFieldNamingStrategy(field -> {
if ( field.getDeclaringClass() == StreamRecord.class ) {
return FieldNamingPolicy.UPPER_CAMEL_CASE.translateName(field);
}
return FieldNamingPolicy.IDENTITY.translateName(field);
})
.create();
I usually never use naming strategies in favor of the #SerializedName annotation though, just to be more precise when declaring mappings.

How to Parse Json Objects of Json Object and of Object (outdated) [duplicate]

This question already has answers here:
How to parse JSON in Java
(36 answers)
Closed 5 years ago.
I'm trying to parse multiple objects,Bellow i'm receiving Json Sample The requirement completed and my question now outdated, can someone please up-vote to help me for asking next question? Will he helpfull for and thanks for
{
"0": //outer objects are multiples, i just post one object for sample
{
"id": "1",
"name": "B2 MR1",
"description":
{
"0": //it is also multiple objects m just showing one
{
"title": "Carve the Future",
"description": "Welcome to Meeting Room 1",
"push_notification": "Carve the Future",
}
}
},//after that the next obj will be show
.
.
}
In second object 1 i also have above keys and values, i can't handel it, here is my Model.
public class JsonModel {
private String id; //getter setter
private String name; //getter setter
List<InnerDescprtion> description; //getter setter
}
Here is my InnerDescprtion Model
private class InnerDescprtion {
private String id; //getter setter
private String title; //getter setter
}
And below is my java code for parsing it using Gson,
JsonModel outterModelClass= null;
List<JsonModel> listObj = new ArrayList<>();
for (int i = 0; i < responseJson.length(); i++) {
try {
outterModelClass= new Gson().fromJson(responseJson.getString(String.valueOf(i)), JsonModel.class);
listObj.add(outterModelClass); //here i'm getting exception,,
} catch (JSONException e) {
e.printStackTrace();
}
}
I get the solution, Please up-vote to help me.
If it is possible for you I would change the json to something like this:
[{
"id": "1",
"name": "B2 MR1",
"description": [{
"id" : "1-1",
"title": "Carve the Future",
"description": "Welcome to Meeting Room 1",
"push_notification": "Carve the Future"
}]
},
{
"id": "2",
"name": "B2 MR2",
"description": [{
"id" : "2-1",
"title": "Carve the Future 2",
"description": "Welcome to Meeting Room 2",
"push_notification": "Carve the Future 2"
}]
}
]
Then your approach should work with just a few changes:
BufferedReader br = new BufferedReader(new FileReader("c:/test/test.json"));
Type listType = new TypeToken<ArrayList<JsonModel>>(){}.getType();
List<JsonModel> outterModels = new Gson().fromJson(br, listType);
If you can't change the json I would suggest to use another JSON library like json simple and extract everything manually.
Your 'listObj' should be defined this way:
ArrayList<JsonModel> listObj = new ArrayList<JsonModel>();
Well that is a nasty looking JSON. However I recommend you use volley android library. I had a task with somewhat similar problem. Only there was a single object inside of another object. To include volley in your project, update your build.gradle app module with compile 'com.android.volley:volley:1.0.0' inside dependencies{}. baseUrl is the url where you are fetching the JSON from.
Then you can do something like:
JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.GET,
baseUrl,
null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
try {
// Parsing json object response
// response will be a json object
for (int i=0; i<response.length(); i++){
JSONObject obj = response.getJSONObject(i);
//id
//name
try{
for (int j=0; j<obj.length() ; j++) {
JSONObject description = obj.getJSONObject(j);
//title
//description
//push notification
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),
"Error: " + e.getMessage(),
Toast.LENGTH_LONG).show();
}
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),
"Error: " + e.getMessage(),
Toast.LENGTH_LONG).show();
}
hidepDialog();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError volleyError) {
VolleyLog.d(TAG,"Error: "+ volleyError.getMessage() );
Toast.makeText(getApplicationContext(), volleyError.getMessage(), Toast.LENGTH_SHORT).show();
hidepDialog();
}
});
//adding request to request queue
AppController.getmInstance().addToRequestQueue(jsonObjReq);
Add this in your parseJSON(){} method or whatever you've named it.
I have not tried doing what you are trying do to. But it seems doable, with the use of volley library.

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