Remove @JsonCreator annotation from Kotlin types

graphql-dgs-codegen-core/build.gradle

@@ -41,6 +41,8 @@ dependencies {
     testImplementation 'com.google.guava:guava:33.4.+'
     testImplementation 'com.google.testing.compile:compile-testing:0.+'
     testImplementation 'org.jetbrains.kotlin:kotlin-compiler'
+
+    integTestImplementation 'com.fasterxml.jackson.module:jackson-module-kotlin'
 }
 
 application {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/Kotlin2CodeGenTest.kt

@@ -18,11 +18,13 @@
 
 package com.netflix.graphql.dgs.codegen
 
+import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
 import org.assertj.core.api.Assertions.assertThat
 import org.assertj.core.api.Assertions.fail
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.params.ParameterizedTest
 import org.junit.jupiter.params.provider.MethodSource
+import java.net.URLClassLoader
 import java.nio.file.Files
 import java.nio.file.Path
 import java.nio.file.Paths
@@ -35,6 +37,7 @@ import kotlin.io.path.readText
 class Kotlin2CodeGenTest {
     // set this to true to update all expected outputs instead of running tests
     private val updateExpected = false
+    private val objectMapper = jacksonObjectMapper()
 
     @ParameterizedTest
     @MethodSource("listTestsToRun")
@@ -160,6 +163,109 @@ class Kotlin2CodeGenTest {
         assertCompilesKotlin(codeGenResult)
     }
 
+    @Test
+    fun `Jackson should deserialize input type with all optional fields without @JsonCreator annotation`() {
+        val schema =
+            """
+            input PersonInput {
+                name: String
+                age: Int
+                email: String
+            }
+            """.trimIndent()
+
+        val result =
+            CodeGen(
+                CodeGenConfig(
+                    schemas = setOf(schema),
+                    packageName = "com.netflix.test.alloptional",
+                    language = Language.KOTLIN,
+                    generateKotlinNullableClasses = true,
+                    generateKotlinClosureProjections = true,
+                ),
+            ).generate()
+
+        val buildDir = assertCompilesKotlin(result)
+        val classLoader = URLClassLoader(arrayOf(buildDir.toUri().toURL()), this.javaClass.classLoader)
+        val inputClass = classLoader.loadClass("com.netflix.test.alloptional.types.PersonInput")
+
+        val json = """{"name": "John", "age": 30, "email": "john@example.com"}"""
+        val instance = objectMapper.readValue(json, inputClass)
+        assertThat(instance).isNotNull
+    }
+
+    @Test
+    fun `Jackson should deserialize input type with required field`() {
+        val schema =
+            """
+            input PersonInput {
+                name: String!
+                age: Int
+                email: String
+            }
+            """.trimIndent()
+
+        val result =
+            CodeGen(
+                CodeGenConfig(
+                    schemas = setOf(schema),
+                    packageName = "com.netflix.test.withrequired",
+                    language = Language.KOTLIN,
+                    generateKotlinNullableClasses = true,
+                    generateKotlinClosureProjections = true,
+                ),
+            ).generate()
+
+        val buildDir = assertCompilesKotlin(result)
+        val classLoader = URLClassLoader(arrayOf(buildDir.toUri().toURL()), this.javaClass.classLoader)
+        val inputClass = classLoader.loadClass("com.netflix.test.withrequired.types.PersonInput")
+
+        // Test runtime Jackson deserialization
+        val json = """{"name": "John", "age": 30, "email": "john@example.com"}"""
+        val instance = objectMapper.readValue(json, inputClass)
+        assertThat(instance).isNotNull
+
+        val nameField = inputClass.getDeclaredField("name")
+        nameField.isAccessible = true
+        assertThat(nameField.get(instance)).isEqualTo("John")
+    }
+
+    @Test
+    fun `Input type with explicit defaults should deserialize without conflicting creators error`() {
+        val schema =
+            """
+            input PersonInput {
+                name: String! = "Unknown"
+                age: Int! = 0
+                active: Boolean! = true
+            }
+            """.trimIndent()
+
+        val result =
+            CodeGen(
+                CodeGenConfig(
+                    schemas = setOf(schema),
+                    packageName = "com.netflix.test.alldefaults",
+                    language = Language.KOTLIN,
+                    generateKotlinNullableClasses = true,
+                    generateKotlinClosureProjections = true,
+                ),
+            ).generate()
+
+        val buildDir = assertCompilesKotlin(result)
+        val classLoader = URLClassLoader(arrayOf(buildDir.toUri().toURL()), this.javaClass.classLoader)
+        val inputClass = classLoader.loadClass("com.netflix.test.alldefaults.types.PersonInput")
+
+        val json = """{"name": "John", "age": 30, "active": false}"""
+
+        val instance = objectMapper.readValue(json, inputClass)
+        assertThat(instance).isNotNull
+
+        val nameField = inputClass.getDeclaredField("name")
+        nameField.isAccessible = true
+        assertThat(nameField.get(instance)).isEqualTo("John")
+    }
+
     companion object {
         @Suppress("unused")
         @JvmStatic

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/constantsForInputTypes/expected/types/PersonFilter.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.constantsForInputTypes.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class PersonFilter @JsonCreator constructor(
+public data class PersonFilter(
   @JsonProperty("email")
   public val email: String? = default<PersonFilter, String?>("email", null),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/constantsWithExtendedInputTypes/expected/types/PersonFilter.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.constantsWithExtendedInputTypes.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
@@ -9,7 +8,7 @@ import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class PersonFilter @JsonCreator constructor(
+public data class PersonFilter(
   @JsonProperty("email")
   public val email: String? = default<PersonFilter, String?>("email", null),
   @JsonProperty("birthYear")

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/dataClassDocs/expected/types/MovieFilter.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.dataClassDocs.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
@@ -13,7 +12,7 @@ import kotlin.collections.List
  *
  * It takes a title and such.
  */
-public data class MovieFilter @JsonCreator constructor(
+public data class MovieFilter(
   @JsonProperty("titleFilter")
   public val titleFilter: String? = default<MovieFilter, String?>("titleFilter", null),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/dataClassFieldDocs/expected/types/MovieFilter.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.dataClassFieldDocs.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class MovieFilter @JsonCreator constructor(
+public data class MovieFilter(
   @JsonProperty("titleFilter")
   public val titleFilter: String? = default<MovieFilter, String?>("titleFilter", null),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/input/expected/types/MovieFilter.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.input.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class MovieFilter @JsonCreator constructor(
+public data class MovieFilter(
   @JsonProperty("genre")
   public val genre: String? = default<MovieFilter, String?>("genre", null),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultBigDecimal/expected/types/OrderFilter.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultBigDecimal.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import java.math.BigDecimal
@@ -9,7 +8,7 @@ import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class OrderFilter @JsonCreator constructor(
+public data class OrderFilter(
   @JsonProperty("min")
   public val min: BigDecimal = default<OrderFilter, BigDecimal>("min", java.math.BigDecimal("1.1")),
   @JsonProperty("avg")

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultCurrency/expected/types/OrderFilter.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultCurrency.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import java.util.Currency
@@ -9,7 +8,7 @@ import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class OrderFilter @JsonCreator constructor(
+public data class OrderFilter(
   @JsonProperty("value")
   public val `value`: Currency = default<OrderFilter, Currency>("value",
       java.util.Currency.getInstance("USD")),

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultEnumValueForArray/expected/types/SomeType.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultEnumValueForArray.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class SomeType @JsonCreator constructor(
+public data class SomeType(
   @JsonProperty("colors")
   public val colors: List<Color?>? = default<SomeType, List<Color?>?>("colors",
       listOf(com.netflix.graphql.dgs.codegen.cases.inputWithDefaultEnumValueForArray.expected.types.Color.red)),

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultIntValueForArray/expected/types/SomeType.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultIntValueForArray.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
@@ -9,7 +8,7 @@ import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class SomeType @JsonCreator constructor(
+public data class SomeType(
   @JsonProperty("numbers")
   public val numbers: List<Int?>? = default<SomeType, List<Int?>?>("numbers", listOf(1, 2, 3)),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultStringValueForArray/expected/types/SomeType.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultStringValueForArray.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class SomeType @JsonCreator constructor(
+public data class SomeType(
   @JsonProperty("names")
   public val names: List<String?>? = default<SomeType, List<String?>?>("names", listOf("A", "B")),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForArray/expected/types/SomeType.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForArray.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class SomeType @JsonCreator constructor(
+public data class SomeType(
   @JsonProperty("names")
   public val names: List<String?>? = default<SomeType, List<String?>?>("names", emptyList()),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForEnum/expected/types/ColorFilter.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForEnum.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class ColorFilter @JsonCreator constructor(
+public data class ColorFilter(
   @JsonProperty("color")
   public val color: Color? = default<ColorFilter, Color?>("color",
       com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForEnum.expected.types.Color.red),

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForNonNullableFields/expected/types/Car.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForNonNullableFields.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class Car @JsonCreator constructor(
+public data class Car(
   @JsonProperty("brand")
   public val brand: String = default<Car, String>("brand", "BMW"),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForNonNullableFields/expected/types/Person.kt

@@ -1,6 +1,5 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForNonNullableFields.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
@@ -10,7 +9,7 @@ import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class Person @JsonCreator constructor(
+public data class Person(
   @JsonProperty("name")
   public val name: String = default<Person, String>("name", "Damian"),
   @JsonProperty("age")

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForObject/expected/types/Car.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForObject.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class Car @JsonCreator constructor(
+public data class Car(
   @JsonProperty("brand")
   public val brand: String = default<Car, String>("brand", "BMW"),
 ) : GraphQLInput() {

graphql-dgs-codegen-core/src/integTest/kotlin/com/netflix/graphql/dgs/codegen/cases/inputWithDefaultValueForObject/expected/types/MovieFilter.kt

@@ -1,14 +1,13 @@
 package com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForObject.expected.types
 
-import com.fasterxml.jackson.`annotation`.JsonCreator
 import com.fasterxml.jackson.`annotation`.JsonProperty
 import com.netflix.graphql.dgs.codegen.GraphQLInput
 import kotlin.Any
 import kotlin.Pair
 import kotlin.String
 import kotlin.collections.List
 
-public data class MovieFilter @JsonCreator constructor(
+public data class MovieFilter(
   @JsonProperty("director")
   public val director: Person? = default<MovieFilter, Person?>("director",
       com.netflix.graphql.dgs.codegen.cases.inputWithDefaultValueForObject.expected.types.Person(name