Does `@JsonCreator` support both DELEGATING mode and PROPERTIES mode deserialization for Enums?

[HaohuaLv]

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Describe the bug

I want to use @JsonCreator on Java enum to achieve deserialization supporting both DELEGATING mode and PROPERTIES mode.
But I found that it may be unavailable for version 2.13.1 (it's ok for version 2.19.2) .
Is there any other way to achieve that for version 2.13.1, or is upgrading the version the only option?

Code:

@Getter
@RequiredArgsConstructor
@JsonFormat(shape = JsonFormat.Shape.OBJECT)
@JsonIncludeProperties({"code", "desc"})
public enum ChannelEnum {

    ALIPAY(0, "支付宝"),
    WECHAT(1, "微信")
    ;
    private final int code;
    private final String desc;

    @Nullable
    @JsonCreator
    private static ChannelEnum ofCode(@JsonProperty("code") String code) {
        if (code == null) {
            return null;
        }
        return Arrays.stream(values()).filter(channelEnum -> channelEnum.getCode() == Integer.parseInt(code)).findFirst().orElse(null);
    }
}

public class CreatorTest extends TestCase {

    private final ObjectMapper objectMapper = new ObjectMapper();

    public void testProperties() throws JsonProcessingException {
        String json = "{\"code\": 1}";
        ChannelEnum channel = objectMapper.readValue(json, ChannelEnum.class);
        Assert.assertSame(channel, ChannelEnum.WECHAT);
    }

    public void testDelegating() throws JsonProcessingException {
        String json = "1";
        ChannelEnum channel = objectMapper.readValue(json, ChannelEnum.class);
        Assert.assertSame(channel, ChannelEnum.WECHAT);
    }

    public void testNoCodeProperty() throws JsonProcessingException {
        String json = "{\"desc\": \"支付宝\"}";
        ChannelEnum channel = objectMapper.readValue(json, ChannelEnum.class);
        Assert.assertNull(channel);
    }
}

stack trace for version 2.13.1

com.fasterxml.jackson.databind.exc.MismatchedInputException: Input mismatch reading Enum `org.examplel.jackson.view.ChannelEnum`: properties-based `@JsonCreator` ([method org.examplel.jackson.view.ChannelEnum#ofCode(java.lang.String)]) expects JSON Object (JsonToken.START_OBJECT), got JsonToken.VALUE_NUMBER_INT
 at [Source: (String)"1"; line: 1, column: 1]

	at com.fasterxml.jackson.databind.exc.MismatchedInputException.from(MismatchedInputException.java:59)
	at com.fasterxml.jackson.databind.DeserializationContext.reportInputMismatch(DeserializationContext.java:1741)
	at com.fasterxml.jackson.databind.deser.std.FactoryBasedEnumDeserializer.deserialize(FactoryBasedEnumDeserializer.java:137)
	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 org.examplel.jackson.view.CreatorTest.testDelegating(CreatorTest.java:28)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at junit.framework.TestCase.runTest(TestCase.java:177)
	at junit.framework.TestCase.runBare(TestCase.java:142)
	at junit.framework.TestResult$1.protect(TestResult.java:122)
	at junit.framework.TestResult.runProtected(TestResult.java:142)
	at junit.framework.TestResult.run(TestResult.java:125)
	at junit.framework.TestCase.run(TestCase.java:130)
	at junit.framework.TestSuite.runTest(TestSuite.java:241)
	at junit.framework.TestSuite.run(TestSuite.java:236)
	at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:90)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
	at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:232)
	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:55)

[cowtowncoder]

2.13.x is not an open branch so if it does not work, no fix will be coming -- but you could try latest 2.13 patch, 2.13.5. I don't see any Enum-related fixes in release notes tho.

However: even with later versions, a single Constructor can only be used in one mode: either Delegating or Properties-based. There is issue #5084 to consider allowing that but it has not yet been implemented.
So I am not sure how this would be working currently for Enums, in any version?

EDIT: see my later comment -- this DOES work for Enums due to ... well, very specialized handling.

[HaohuaLv]

2.13.x is not an open branch so if it does not work, no fix will be coming -- but you could try latest 2.13 patch, 2.13.5. I don't see any Enum-related fixes in release notes tho.

However: even with later versions, a single Constructor can only be used in one mode: either Delegating or Properties-based. There is issue #5084 to consider allowing that but it has not yet been implemented. So I am not sure how this would be working currently for Enums, in any version?

Alright, I want to use @jsonformat(shape = JsonFormat.Shape.OBJECT) on an enum and allow the front end to request using the Delegating mode. However, if Delegating and Properties are incompatible, it could lead to a very awkward situation: the result serialized from the enum itself cannot be deserialized.

[cowtowncoder]

Ok: apparently this DOES work: I added verification in 3.x, but I assume it works for some 2.x versions.

I will mark it as fixed for 2.19.0 but probably was working before that. If anyone has more knowledge feel free to add info on earlier working versions.

Closing.