Deserialization fails with ImmutableList in Jackson 2.18.3 #5381
Description
Jackson 2.18.3 fails to deserialize classes with @Builder (Lombok) and ImmutableList (Guava) fields. This worked in Jackson 2.18.1 but breaks after upgrading to 2.18.3 (via Spring Boot 3.4.0 → 3.4.5).
Error
com.fasterxml.jackson.databind.exc.InvalidDefinitionException:
Cannot construct instance of com.google.common.collect.ImmutableList
(no Creators, like default constructor, exist)
Code that fails
@Builder
@Getter
@AllArgsConstructor
@NoArgsConstructor(access = PRIVATE)
class MimirAssertsRelabelRules {
private ImmutableList<MimirRelabelRuleGroup> asserts;
}
ObjectMapper mapper = new ObjectMapper()
.registerModule(new GuavaModule());
// This throws InvalidDefinitionException
mapper.readValue(json, MimirAssertsRelabelRules.class);Workaround that works
Add @JsonCreator to force constructor-based deserialization:
@Builder
@Getter
@AllArgsConstructor
@NoArgsConstructor(access = PRIVATE)
class MimirAssertsRelabelRules {
private ImmutableList<MimirRelabelRuleGroup> asserts;
@JsonCreator
public static MimirAssertsRelabelRules fromJson(@JsonProperty("asserts") List<MimirRelabelRuleGroup> asserts) {
return new MimirAssertsRelabelRules(
asserts != null ? ImmutableList.copyOf(asserts) : ImmutableList.of()
);
}
}This works because it bypasses the builder pattern and uses constructor-based deserialization.
Question
Can anyone help explain why this changed between 2.18.1 and 2.18.3?