I keep getting following exception while reading data from cache.
org.springframework.data.redis.serializer.SerializationException: Could not read JSON: Cannot construct instance of `java.time.Instant` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
It started as soon as I introduced new variable of type java.time.Instant
You can use JsonSerializer and JsonDeserializer to serialize Instant object either as milliseconds or custom text format.
For example implementation follow the answer section of How to set format of string for java.time.Instant using objectMapper?
Related
I am trying to test my JSON based webservice using Junit client. I get a ClientHandlerException for not having no-arg default constructor' on my request object and its super class (AMessageStrategy). When I add theno-arg default constructorto both of them the server throws a exceptionNo suitable constructor found for type [simple type, class javax.xml.bind.JAXBElement]:`. This has put me in a fix.
Ideally I dont want/need to have a no-arg default constructor. The question is, is there a way around it. I just need to serialize a object to json. The object has 2 main fields, a message id and message data. The message data is a pojo.
I have added #XmlRootElement on the request class (no annotations on the fields though).
Please advice, I am kinda stuck. And I am a newbie on Java EE. Let me know if more information is needed on this.
com.sun.jersey.api.client.ClientHandlerException: javax.ws.rs.WebApplicationException: com.sun.xml.internal.bind.v2.runtime.IllegalAnnotationsException: 2 counts of IllegalAnnotationExceptions
com.mcruiseon.common.message.request.RegistrationRequest does not have a no-arg default constructor.
this problem is related to the following location:
at com.mcruiseon.common.message.request.RegistrationRequest
com.mcruiseon.common.message.AMessageStrategy does not have a no-arg default constructor.
this problem is related to the following location:
at com.mcruiseon.common.message.AMessageStrategy
at com.mcruiseon.common.message.request.RegistrationRequest
at com.sun.jersey.client.urlconnection.URLConnectionClientHandler.handle(URLConnectionClientHandler.java:151)
at com.sun.jersey.api.client.Client.handle(Client.java:648)
at com.sun.jersey.api.client.WebResource.handle(WebResource.java:680)
at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
at com.sun.jersey.api.client.WebResource$Builder.post(WebResource.java:568)
at test.carpool4all.Registration.testPost(Registration.java:74)
RegistrationRequest is not a POJO. Ideally it should be a POJO for it to work.
When parsing Json with the Jerkson library following the example in the docs:
case class Person(id: Long, name: String)
parse[Person]("""{"id":1,"name":"Coda"}""") //=> Person(1,"Coda")
If I try and deserialize Json that doesn't contain both the id and the name fields then an error is thrown saying they are needed. Is there a way of setting it up so that if the following Json for a Person was parsed:
{"id":2}
The name field could be defaulted to "John". (I thought this might be possible by setting a default in the parameter in the case class but no luck)
Check out this pull request I did for the Jerkson library. It adds support for case class default parameters.
Pay heed to user ksvladimir's comment, though, which I haven't had time to add to the pull request. (I'll update this answer when I do)
I'm facing following error while trying unmarshal java.util.Date from JSON in grails controller.
org.codehaus.groovy.runtime.typehandling.GroovyCastException: Cannot cast object '2011-10-07 10:24:40' with class 'java.lang.String' to class 'java.util.Date'**
Also, I've tried the following method but still no luck, actually I've doubt wether I've implemented following in right way or not because when i put println statements in following method:
public CustomDateBinder(List formats)
Nothing prints on console.
Grails Date unmarshalling
According to the description of your error message you are trying to convert a String to Date, if you want to do it manually you can use the following method in your Controller (since Grails 2)
def val = params.date('myDate', 'dd-MM-yyyy') //Obviously you need to change the format
Check the following post for more info: http://mrhaki.blogspot.com/2012/01/grails-goodness-date-request-parameter.html
My server returns a list of objects in JSON. They might be Cats or Dogs, for example.
When I know that they'll all be Cats, I can set the AutoBeanCodex to work easily. When I don't know what types they are, though... what should I do?
I could give all of my entities a type field, but then I'd have to parse each entity before passing it to the AutoBeanCodex, which borders on defeating the point. What other options do I have?
Just got to play with this the other day, and fought it for a few hours, trying #Category methods and others, until I found this: You can create a property of type Splittable, which represents the underlying transport type that has some encoding for booleans/Strings/Lists/Maps. In my case, I know some enveloping type that goes over the wire at design time, and based on some other property, some other field can be any number of other autobeans.
You don't even need to know the type of the other bean at compile time, you could get values out using Splittable's methods, but if using autobeans anyway, it is nice to define the data that is wrapped.
interface Envelope {
String getStatus();
String getDataType();
Splittable getData();
}
(Setters might be desired if you sending data as well as recieving - encoding a bean into a `Splittable to send it in an envelope is even easier than decoding it)
The JSON sent over the wire is decoded (probably using AutoBeanCodex) into the Envelope type, and after you've decided what type must be coming out of the getData() method, call something like this to get the nested object out
SpecificNestedBean bean = AutoBeanCodex.decode(factory,
SpecificNestedBean.class,
env.getData()).as();
The Envelope type and the nested types (in factory above) don't even need to be the same AutoBeanFactory type. This could allow you to abstract out the reading/writing of envelopes from the generic transport instance, and use a specific factory for each dataType string property to decode the data's model (and nested models).
I have a request parameter in my ASP.NET app. that is in JSON format, and I was wondering if there is a good (quick and easy) way to convert a JSON string to a Jayrocks JsonObject, so I can easily extract key-value pairs without the need to manually parse the string?
Assuming json is the variable containing JSON text, use Jayrock.Json.Conversion.JsonConvert.Import(json). What you will get back in return is either a JsonObject, JsonArray, JsonNumber, System.String, System.Boolean or a null reference depending on the root JSON value in the source JSON text. If you know it is going to be a JSON object for sure then you can safely cast the return value or use JsonConvert.Import<JsonObject>(json).
I would discourage working against JsonObject directly unless you particularly depend on one of its features. You should just pretend the JSON object you get back is a dictionary; either IDictionary or IDictionary<string, object>. With the latest version for .NET Framework 4, you can also work with a JsonObject as a dynamic object.
I don't know Jayrock, but if you want to accept a JSON object as a parameter of Action in MVC2 than the easiest way to do it is by using JsonValueProviderFactory from Futures assembly.
It's part of System.Web.Mvc in MVC3.