Unwrapped lists cannot be deserialized when using JsonTypeInfo.As.EXISTING_PROPERTY (original) (raw)

If the UnwrappedPolymorphicList490Test is changed to the following:

package com.fasterxml.jackson.dataformat.xml.lists;

import java.util.*;

import org.junit.jupiter.api.Test;

import com.fasterxml.jackson.annotation.*; import com.fasterxml.jackson.dataformat.xml.XmlMapper; import com.fasterxml.jackson.dataformat.xml.XmlTestUtil;

import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertNotNull;

public class UnwrappedPolymorphicList490Test extends XmlTestUtil { @JsonTypeInfo( use = JsonTypeInfo.Id.NAME,

•       include = JsonTypeInfo.As.EXISTING_PROPERTY,
        property = "type")

  @JsonSubTypes({ @JsonSubTypes.Type(value = MyType490.class, name = "myType"), }) interface IMyType490 { }

  static class MyType490 implements IMyType490 { public final String stringValue;

•   public final String type = "myType";
    public final Collection<String> typeNames;
  
    @JsonCreator
    public MyType490(
            @JsonProperty("stringValue") String stringValue,
            @JsonProperty("typeNames") Collection<String> typeNames) {
        this.stringValue = stringValue;
        this.typeNames = typeNames;
    }

  }

  // [dataformat-xml#490] @Test public void testPolymorphicUnwrappedList490() throws Exception { XmlMapper xmlMapper = XmlMapper.builder() .defaultUseWrapper(false).build(); List typeNames = new ArrayList<>(); typeNames.add("type1"); typeNames.add("type2"); MyType490 input = new MyType490("hello", typeNames); String doc = xmlMapper.writeValueAsString(input); IMyType490 result = xmlMapper.readValue(doc, IMyType490.class);
  assertNotNull(result); assertEquals(MyType490.class, result.getClass()); MyType490 typedResult = (MyType490) result; assertEquals(Arrays.asList("type1", "type2"), typedResult.typeNames); }

}

the deserialization breaks with this error:

com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `java.util.ArrayList` (although at least one Creator exists): no String-argument constructor/factory method to deserialize from String value ('type1')
 at [Source: (StringReader); line: 1, column: 112] (through reference chain: com.fasterxml.jackson.dataformat.xml.lists.UnwrappedPolymorphicList490Test$MyType490["typeNames"])

Is that to be expected?