Can I deserialize a data class with an unsigned member in the constructor?

[hanzo2001]

Can I deserialize a data class with an unsigned member in the constructor?

Jackson 2.13.4

I am working with some unsigned numbers and I know that I will be deserializing incoming json. I would like to directly map the numbers to their unsigned representation. I checked #525 and #524 and upgraded to 2.13.4

I am seeing an error that does not make sense

Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of A (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)

My simplified model clearly has a no-arg constructor (like all my other data classes that do work)

data class A(
    var a: String = "",
    var b: ULong = 0U,
)

Am I doing something wrong? Is this a bug?

My test case:

class DataClassConstructorWithUnsignedTest {

    @Test
    fun a() {

        val a1 = A()
        val mapper = jacksonObjectMapper()
        val serialized = mapper.writeValueAsString(a1)
            .also(::println)

        assertDoesNotThrow {
            val deserialized = mapper.readValue(serialized, A::class.java)
                .also(::println)
        }
    }
}

Stack trace

org.opentest4j.AssertionFailedError: Unexpected exception thrown: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `A` (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator) at [Source: (String)"{"a":"","b":0}"; line: 1, column: 2]
	at DataClassConstructorWithUnsignedTest.a(DataClassConstructorWithUnsignedTest.kt:17)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
	at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `A` (no Creators, like default constructor, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (String)"{"a":"","b":0}"; line: 1, column: 2]
	at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)
	at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1904)
	at com.fasterxml.jackson.databind.DatabindContext.reportBadDefinition(DatabindContext.java:400)
	at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1349)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1415)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:351)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:184)
	at com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:322)
	at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4674)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3629)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3597)
	at DataClassConstructorWithUnsignedTest$a$1.invoke(DataClassConstructorWithUnsignedTest.kt:19)

[hanzo2001]

I see that someone else asked this in #573

[hanzo2001]

This question is subordinate to a longer discussion on #199

[k163377]

As you say, deserialization of value class is not yet supported.
Progress will be reported in #199, so this issue is closed.