Re: Possible problem with JsonbSerializer

[Xavier Dury]

Hi Romain,

I tested your modification and it's working for serialization but it fails for 
deserialization:

        public static class UUIDSerializer implements JsonbSerializer<UUID> {
                public void serialize(UUID obj, JsonGenerator generator, 
SerializationContext ctx) {
                        generator.write(obj.toString());
                }
        }

        public static class UUIDDeserializer implements JsonbDeserializer<UUID> 
{
                public UUID deserialize(JsonParser parser, 
DeserializationContext ctx, Type rtType) {
                        return UUID.fromString(parser.getString());
                }
        }

        public static class UUIDHolder {
                @JsonbTypeSerializer(UUIDSerializer.class)
                @JsonbTypeDeserializer(UUIDDeserializer.class)
                public UUID uuid = UUID.randomUUID();
        }

        @Test
        public void testIt() {
                Jsonb jsonb = JsonbBuilder.create();
                StringWriter w = new StringWriter();
                jsonb.toJson(new UUIDHolder(), w);
                jsonb.fromJson(w.toString(), UUIDHolder.class);
        }

java.lang.UnsupportedOperationException: Array handling with ObjectConverter 
currently not implemented
        at 
org.apache.johnzon.mapper.MappingParserImpl.toValue(MappingParserImpl.java:736)
        at 
org.apache.johnzon.mapper.MappingParserImpl.buildObject(MappingParserImpl.java:338)
        at 
org.apache.johnzon.mapper.MappingParserImpl.readObject(MappingParserImpl.java:141)
        at 
org.apache.johnzon.mapper.MappingParserImpl.readObject(MappingParserImpl.java:133)
        at 
org.apache.johnzon.mapper.MappingParserImpl.readObject(MappingParserImpl.java:125)
        at org.apache.johnzon.mapper.Mapper.mapObject(Mapper.java:328)
        at org.apache.johnzon.mapper.Mapper.readObject(Mapper.java:267)
        at org.apache.johnzon.mapper.Mapper.readObject(Mapper.java:262)
        at org.apache.johnzon.jsonb.JohnzonJsonb.fromJson(JohnzonJsonb.java:60)

Xavier

________________________________________
From: Xavier Dury <kal...@hotmail.com>
Sent: Tuesday, April 2, 2019 3:46 PM
To: dev@johnzon.apache.org
Subject: Re: Possible problem with JsonbSerializer

Hi Romain,

yes it is a duplicate... I sent the first mail before confirming my 
subscription to the mailing list (first time posting) then sent it a second 
time not knowing the first one would be sent anyway after the confirmation... 
sorry about that.

Xavier

________________________________________
From: Romain Manni-Bucau <rmannibu...@gmail.com>
Sent: Tuesday, April 2, 2019 3:17 PM
To: dev@johnzon.apache.org
Subject: Re: Possible problem with JsonbSerializer

Hi Xavier,

is it a duplicate - or did I mess up my inbox?

In any case i opened https://issues.apache.org/jira/browse/JOHNZON-207 and
pushed a first fix if you want to have a look.

Romain Manni-Bucau
@rmannibucau <https://twitter.com/rmannibucau> |  Blog
<https://rmannibucau.metawerx.net/> | Old Blog
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LinkedIn <https://www.linkedin.com/in/rmannibucau> | Book
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Le mar. 2 avr. 2019 à 14:00, Xavier Dury <kal...@hotmail.com> a écrit :

> Hi,
>
> When trying the following code on Johnzon 1.1.12-SNAPSHOT:
>
>     public class UUIDSerializer implements JsonbSerializer<UUID> {
>         public void serialize(UUID obj, JsonGenerator generator,
> SerializationContext ctx) {
>             generator.flush();
>             System.out.println("!!!");
>             generator.write(obj.toString());
>         }
>     }
>
>     public class UUIDHolder {
>         @JsonbTypeSerializer(UUIDSerializer.class)
>         public UUID uuid = UUID.randomUUID();
>     }
>
>     JsonbBuilder.create().toJson(new UUIDHolder(), System.out);
>
> I get the following printed on System.out:
>
>     {"uuid":{!!!
>
> and an exception:
>
> javax.json.stream.JsonGenerationException: write(param) is only valid in
> arrays
>         at
> org.apache.johnzon.core.JsonGeneratorImpl.checkArray(JsonGeneratorImpl.java:623)
>         at
> org.apache.johnzon.core.JsonGeneratorImpl.write(JsonGeneratorImpl.java:384)
>         at
> org.apache.johnzon.jsonb.SerializerTest$ConcreteSerializer.serialize(SerializerTest.java:249)
>         at
> org.apache.johnzon.jsonb.SerializerTest$ConcreteSerializer.serialize(SerializerTest.java:1)
>         at
> org.apache.johnzon.jsonb.JsonbAccessMode$WriterConverters.lambda$0(JsonbAccessMode.java:793)
>         at
> org.apache.johnzon.mapper.MappingGeneratorImpl.writeValue(MappingGeneratorImpl.java:381)
>
> This looks kinda strange to me because, it seems that Johnzon tries to
> start a new object (hence the opening bracket in the output in front of the
> '!!!') before it passes control to the serializer. Why does Johnzon do
> that? The serializer could decide that the object could be stored as an
> object ({}), an array ([]) or a primitive value.
>
> Should I report an issue?
>
> Regards,
> Xavier