Kotlin: minimize the usage of 'JvmSuppressWildcards'

CHANGELOG.md

@@ -4,6 +4,7 @@
  * Kotlin: use `@JvmSynthetic` annotation for Kotlin internal elements whenever possible to hide them from Java code.
  * Kotlin: allow the usage of 'RequiresOptIn' and 'OptIn' annotations for internal API via CLI parameters. This way error is generated when the code, which is not intended to access the internal API uses it. Three new CLI parameters are available: 'androidrequiresoptinannotation', 'androidoptinannotation' and 'androidinternalapiannotationname'.
  * Kotlin: for external types usage in Kotlin, use 'internal' keyword for the types, which are generated by Gluecodium as their 'internal' representation.
+ * Kotlin: minimize the usage of 'JvmSuppressWildcards' annotation for collection parameters. This annotation was used for all generated collection types. It needs to be used only when collection type holds another open type e.g.: 'open class', 'interface' or 'fun interface'.
 
 ## 14.0.0
 Release date 2025-12-01

gluecodium/src/main/java/com/here/gluecodium/generator/kotlin/KotlinNameResolver.kt

@@ -29,6 +29,7 @@ import com.here.gluecodium.model.lime.LimeAttributeValueType.FUNCTION_NAME
 import com.here.gluecodium.model.lime.LimeBasicType
 import com.here.gluecodium.model.lime.LimeBasicType.TypeId
 import com.here.gluecodium.model.lime.LimeComment
+import com.here.gluecodium.model.lime.LimeContainerWithInheritance
 import com.here.gluecodium.model.lime.LimeDirectTypeRef
 import com.here.gluecodium.model.lime.LimeElement
 import com.here.gluecodium.model.lime.LimeExternalDescriptor.Companion.NAME_NAME
@@ -164,14 +165,28 @@ internal class KotlinNameResolver(
 
     private fun resolveGenericTypeRef(limeType: LimeGenericType) =
         when (limeType) {
-            is LimeList -> "List<@JvmSuppressWildcards ${resolveTypeRef(limeType.elementType)}>"
-            is LimeSet -> "Set<@JvmSuppressWildcards ${resolveTypeRef(limeType.elementType)}>"
-            is LimeMap -> "Map<@JvmSuppressWildcards ${resolveTypeRef(
-                limeType.keyType,
-            )}, @JvmSuppressWildcards ${resolveTypeRef(limeType.valueType)}>"
+            is LimeList -> "List<${resolveContainerParamType(limeType.elementType)}>"
+            is LimeSet -> "Set<${resolveContainerParamType(limeType.elementType)}>"
+            is LimeMap -> "Map<${resolveContainerParamType(limeType.keyType)}, ${resolveContainerParamType(limeType.valueType)}>"
             else -> throw GluecodiumExecutionException("Unsupported element type ${limeType.javaClass.name}")
         }
 
+    private fun resolveContainerParamType(typeRef: LimeTypeRef) =
+        if (needsToSuppressWildcards(typeRef.type)) {
+            "@JvmSuppressWildcards ${resolveTypeRef(typeRef)}"
+        } else {
+            resolveTypeRef(typeRef)
+        }
+
+    // The parameters of generic types (List, Set, Map) must use '@JvmSuppressWildcards'
+    // for 'open' types to avoid compilation problems when accessed from Java code.
+    private fun needsToSuppressWildcards(type: LimeType) =
+        when (type) {
+            is LimeContainerWithInheritance -> type.isOpen
+            is LimeLambda -> true
+            else -> false
+        }
+
     private fun resolveNestedNames(limeElement: LimeNamedElement): List<String> {
         val elementName = kotlinNameRules.getName(limeElement)
         val parentElement = if (limeElement.path.hasParent) getParentElement(limeElement) else null

gluecodium/src/test/resources/smoke/constants/output/android-kotlin/com/example/smoke/CollectionConstants.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("CollectionConstantsExtensions")
 
+
 package com.example.smoke
 
 import com.example.NativeBase
@@ -29,10 +30,10 @@ class CollectionConstants : NativeBase {
 
 
     companion object {
-        @JvmField final val LIST_CONSTANT: List<@JvmSuppressWildcards String> = mutableListOf("foo", "bar")
-        @JvmField final val SET_CONSTANT: Set<@JvmSuppressWildcards String> = mutableSetOf("foo", "bar")
-        @JvmField final val MAP_CONSTANT: Map<@JvmSuppressWildcards String, @JvmSuppressWildcards String> = mutableMapOf("foo" to "bar")
-        @JvmField final val MIXED_CONSTANT: Map<@JvmSuppressWildcards List<@JvmSuppressWildcards String>, @JvmSuppressWildcards Set<@JvmSuppressWildcards String>> = mutableMapOf(mutableListOf("foo") to mutableSetOf("bar"))
+        @JvmField final val LIST_CONSTANT: List<String> = mutableListOf("foo", "bar")
+        @JvmField final val SET_CONSTANT: Set<String> = mutableSetOf("foo", "bar")
+        @JvmField final val MAP_CONSTANT: Map<String, String> = mutableMapOf("foo" to "bar")
+        @JvmField final val MIXED_CONSTANT: Map<List<String>, Set<String>> = mutableMapOf(mutableListOf("foo") to mutableSetOf("bar"))
         @JvmStatic private external fun disposeNativeHandle(nativeHandle: Long)
     }
 }

gluecodium/src/test/resources/smoke/constructors/output/android-kotlin/com/example/smoke/Constructors.kt

@@ -43,7 +43,7 @@ open class Constructors : NativeBase {
     }
 
 
-    constructor(input: List<@JvmSuppressWildcards Double>) : this(create(input), null as Any?) {
+    constructor(input: List<Double>) : this(create(input), null as Any?) {
         cacheThisInstance();
     }
 
@@ -79,7 +79,7 @@ open class Constructors : NativeBase {
         @Throws(Constructors.ConstructorExplodedException::class)
         @JvmStatic private external fun create(input: String) : Long
 
-        @JvmStatic private external fun create(input: List<@JvmSuppressWildcards Double>) : Long
+        @JvmStatic private external fun create(input: List<Double>) : Long
 
         @JvmStatic private external fun create(input: Long) : Long
     }

gluecodium/src/test/resources/smoke/dates/output/android-kotlin/com/example/smoke/Dates.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("DatesExtensions")
 
+
 package com.example.smoke
 
 import com.example.NativeBase
@@ -53,7 +54,7 @@ class Dates : NativeBase {
         external get
         external set
 
-    var dateSet: Set<@JvmSuppressWildcards Date>
+    var dateSet: Set<Date>
         external get
         external set
 

gluecodium/src/test/resources/smoke/defaults/output/android-kotlin/com/example/smoke/DefaultValues.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("DefaultValuesExtensions")
 
+
 package com.example.smoke
 
 import com.example.NativeBase
@@ -85,11 +86,11 @@ class DefaultValues : NativeBase {
     }
 
     class StructWithEmptyDefaults {
-        @JvmField var intsField: List<@JvmSuppressWildcards Int>
-        @JvmField var floatsField: List<@JvmSuppressWildcards Float>
-        @JvmField var mapField: Map<@JvmSuppressWildcards Long, @JvmSuppressWildcards String>
+        @JvmField var intsField: List<Int>
+        @JvmField var floatsField: List<Float>
+        @JvmField var mapField: Map<Long, String>
         @JvmField var structField: DefaultValues.StructWithDefaults
-        @JvmField var setTypeField: Set<@JvmSuppressWildcards String>
+        @JvmField var setTypeField: Set<String>
 
 
 

gluecodium/src/test/resources/smoke/defaults_const/output/android-kotlin/com/example/smoke/EnumCollectionDefaults.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("EnumCollectionDefaultsExtensions")
 
+
 package com.example.smoke
 
 import com.example.fire.Enum1
@@ -14,9 +15,9 @@ import com.example.fire.Enum4
 import java.util.EnumSet
 
 class EnumCollectionDefaults {
-    @JvmField var listField: List<@JvmSuppressWildcards Enum1>
-    @JvmField var setField: Set<@JvmSuppressWildcards Enum2>
-    @JvmField var mapField: Map<@JvmSuppressWildcards Enum3, @JvmSuppressWildcards Enum4>
+    @JvmField var listField: List<Enum1>
+    @JvmField var setField: Set<Enum2>
+    @JvmField var mapField: Map<Enum3, Enum4>
 
 
 

gluecodium/src/test/resources/smoke/defaults_const/output/android-kotlin/com/example/smoke/EnumCollectionDefaultsExternal.kt

@@ -5,14 +5,15 @@
 
 @file:JvmName("EnumCollectionDefaultsExternalExtensions")
 
+
 package com.example.smoke
 
 import java.util.EnumSet
 
 class EnumCollectionDefaultsExternal {
-    @JvmField var listField: List<@JvmSuppressWildcards foo.AlienEnum1>
-    @JvmField var setField: Set<@JvmSuppressWildcards foo.AlienEnum2>
-    @JvmField var mapField: Map<@JvmSuppressWildcards foo.AlienEnum3, @JvmSuppressWildcards foo.AlienEnum4>
+    @JvmField var listField: List<foo.AlienEnum1>
+    @JvmField var setField: Set<foo.AlienEnum2>
+    @JvmField var mapField: Map<foo.AlienEnum3, foo.AlienEnum4>
 
 
 

gluecodium/src/test/resources/smoke/defaults_const/output/android-kotlin/com/example/smoke/InternalEnumDefaults.kt

@@ -5,14 +5,15 @@
 
 @file:JvmName("InternalEnumDefaultsExtensions")
 
+
 package com.example.smoke
 
 
 class InternalEnumDefaults {
     @JvmField var publicField: FooBarEnum
-    @JvmField var publicListField: List<@JvmSuppressWildcards FooBarEnum>
+    @JvmField var publicListField: List<FooBarEnum>
     @JvmField @JvmSynthetic internal var internalField: FooBarEnum
-    @JvmField @JvmSynthetic internal var internalListField: List<@JvmSuppressWildcards FooBarEnum>
+    @JvmField @JvmSynthetic internal var internalListField: List<FooBarEnum>
 
 
 

gluecodium/src/test/resources/smoke/equatable/output/android-kotlin/com/example/smoke/Equatable.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("EquatableExtensions")
 
+
 package com.example.smoke
 
 
@@ -23,12 +24,12 @@ class Equatable {
         @JvmField var stringField: String
         @JvmField var structField: Equatable.NestedEquatableStruct
         @JvmField var enumField: Equatable.SomeEnum
-        @JvmField var arrayField: List<@JvmSuppressWildcards String>
-        @JvmField var mapField: Map<@JvmSuppressWildcards Int, @JvmSuppressWildcards String>
+        @JvmField var arrayField: List<String>
+        @JvmField var mapField: Map<Int, String>
 
 
 
-        constructor(boolField: Boolean, intField: Int, longField: Long, floatField: Float, doubleField: Double, stringField: String, structField: Equatable.NestedEquatableStruct, enumField: Equatable.SomeEnum, arrayField: List<@JvmSuppressWildcards String>, mapField: Map<@JvmSuppressWildcards Int, @JvmSuppressWildcards String>) {
+        constructor(boolField: Boolean, intField: Int, longField: Long, floatField: Float, doubleField: Double, stringField: String, structField: Equatable.NestedEquatableStruct, enumField: Equatable.SomeEnum, arrayField: List<String>, mapField: Map<Int, String>) {
             this.boolField = boolField
             this.intField = intField
             this.longField = longField
@@ -91,8 +92,8 @@ class Equatable {
         @JvmField var stringField: String?
         @JvmField var structField: Equatable.NestedEquatableStruct?
         @JvmField var enumField: Equatable.SomeEnum?
-        @JvmField var arrayField: List<@JvmSuppressWildcards String>?
-        @JvmField var mapField: Map<@JvmSuppressWildcards Int, @JvmSuppressWildcards String>?
+        @JvmField var arrayField: List<String>?
+        @JvmField var mapField: Map<Int, String>?
 
 
 

gluecodium/src/test/resources/smoke/equatable/output/android-kotlin/com/example/smoke/EquatableStructWithInternalFields.kt

@@ -5,19 +5,20 @@
 
 @file:JvmName("EquatableStructWithInternalFieldsExtensions")
 
+
 package com.example.smoke
 
 
 class EquatableStructWithInternalFields {
     @JvmField var publicField: String
     @JvmField @JvmSynthetic internal var internalField: String
-    @JvmField @JvmSynthetic internal var internalListField: List<@JvmSuppressWildcards String>
-    @JvmField @JvmSynthetic internal var internalMapField: Map<@JvmSuppressWildcards String, @JvmSuppressWildcards String>
-    @JvmField @JvmSynthetic internal var internalSetField: Set<@JvmSuppressWildcards String>
+    @JvmField @JvmSynthetic internal var internalListField: List<String>
+    @JvmField @JvmSynthetic internal var internalMapField: Map<String, String>
+    @JvmField @JvmSynthetic internal var internalSetField: Set<String>
 
 
 
-    internal constructor(publicField: String, internalField: String, internalListField: List<@JvmSuppressWildcards String>, internalMapField: Map<@JvmSuppressWildcards String, @JvmSuppressWildcards String>, internalSetField: Set<@JvmSuppressWildcards String>) {
+    internal constructor(publicField: String, internalField: String, internalListField: List<String>, internalMapField: Map<String, String>, internalSetField: Set<String>) {
         this.publicField = publicField
         this.internalField = internalField
         this.internalListField = internalListField

gluecodium/src/test/resources/smoke/escaped_names/output/android-kotlin/com/example/package/Class.kt

@@ -33,7 +33,7 @@ class Class : NativeBase, Interface {
 
 
     @Throws(Types.ExceptionException::class)
-    external fun Fun(double: List<@JvmSuppressWildcards Types.Struct>) : Types.Struct
+    external fun Fun(double: List<Types.Struct>) : Types.Struct
 
     var Property: Types.Enum
         external get

gluecodium/src/test/resources/smoke/external_types/output/android-kotlin/com/example/smoke/Structs.kt

@@ -5,6 +5,7 @@
 
 @file:JvmName("StructsExtensions")
 
+
 package com.example.smoke
 
 import com.example.NativeBase
@@ -14,12 +15,12 @@ class Structs : NativeBase {
     class ExternalStruct {
         @JvmField var stringField: String
         @JvmField var externalStringField: String
-        @JvmField var externalArrayField: List<@JvmSuppressWildcards Byte>
+        @JvmField var externalArrayField: List<Byte>
         @JvmField var externalStructField: Structs.AnotherExternalStruct
 
 
 
-        constructor(stringField: String, externalStringField: String, externalArrayField: List<@JvmSuppressWildcards Byte>, externalStructField: Structs.AnotherExternalStruct) {
+        constructor(stringField: String, externalStringField: String, externalArrayField: List<Byte>, externalStructField: Structs.AnotherExternalStruct) {
             this.stringField = stringField
             this.externalStringField = externalStringField
             this.externalArrayField = externalArrayField

gluecodium/src/test/resources/smoke/generic_types/output/android-kotlin/com/example/smoke/EnumSets.kt

@@ -5,12 +5,13 @@
 
 @file:JvmName("EnumSetsExtensions")
 
+
 package com.example.smoke
 
 import java.util.EnumSet
 
 class EnumSets {
-    @JvmField var enumSetField: Set<@JvmSuppressWildcards GenericTypesWithCompoundTypes.SomeEnum>
+    @JvmField var enumSetField: Set<GenericTypesWithCompoundTypes.SomeEnum>
 
 
 
@@ -23,7 +24,7 @@ class EnumSets {
 
 
     companion object {
-        @JvmField final val ENUM_SET_CONST: Set<@JvmSuppressWildcards GenericTypesWithCompoundTypes.SomeEnum> = EnumSet.of(GenericTypesWithCompoundTypes.SomeEnum.FOO, GenericTypesWithCompoundTypes.SomeEnum.BAR)
+        @JvmField final val ENUM_SET_CONST: Set<GenericTypesWithCompoundTypes.SomeEnum> = EnumSet.of(GenericTypesWithCompoundTypes.SomeEnum.FOO, GenericTypesWithCompoundTypes.SomeEnum.BAR)
     }
 }
 

gluecodium/src/test/resources/smoke/generic_types/output/android-kotlin/com/example/smoke/GenericTypesWithBasicTypes.kt

@@ -5,20 +5,21 @@
 
 @file:JvmName("GenericTypesWithBasicTypesExtensions")
 
+
 package com.example.smoke
 
 import com.example.NativeBase
 
 class GenericTypesWithBasicTypes : NativeBase {
 
     class StructWithGenerics {
-        @JvmField var numbersList: List<@JvmSuppressWildcards Short>
-        @JvmField var numbersMap: Map<@JvmSuppressWildcards Short, @JvmSuppressWildcards String>
-        @JvmField var numbersSet: Set<@JvmSuppressWildcards Short>
+        @JvmField var numbersList: List<Short>
+        @JvmField var numbersMap: Map<Short, String>
+        @JvmField var numbersSet: Set<Short>
 
 
 
-        constructor(numbersList: List<@JvmSuppressWildcards Short>, numbersMap: Map<@JvmSuppressWildcards Short, @JvmSuppressWildcards String>, numbersSet: Set<@JvmSuppressWildcards Short>) {
+        constructor(numbersList: List<Short>, numbersMap: Map<Short, String>, numbersSet: Set<Short>) {
             this.numbersList = numbersList
             this.numbersMap = numbersMap
             this.numbersSet = numbersSet
@@ -45,32 +46,32 @@ class GenericTypesWithBasicTypes : NativeBase {
 
 
 
-    external fun methodWithList(input: List<@JvmSuppressWildcards Int>) : List<@JvmSuppressWildcards Int>
+    external fun methodWithList(input: List<Int>) : List<Int>
 
 
-    external fun methodWithMap(input: Map<@JvmSuppressWildcards Int, @JvmSuppressWildcards Boolean>) : Map<@JvmSuppressWildcards Int, @JvmSuppressWildcards Boolean>
+    external fun methodWithMap(input: Map<Int, Boolean>) : Map<Int, Boolean>
 
 
-    external fun methodWithSet(input: Set<@JvmSuppressWildcards Int>) : Set<@JvmSuppressWildcards Int>
+    external fun methodWithSet(input: Set<Int>) : Set<Int>
 
 
-    external fun methodWithListTypeAlias(input: List<@JvmSuppressWildcards String>) : List<@JvmSuppressWildcards String>
+    external fun methodWithListTypeAlias(input: List<String>) : List<String>
 
 
-    external fun methodWithMapTypeAlias(input: Map<@JvmSuppressWildcards String, @JvmSuppressWildcards String>) : Map<@JvmSuppressWildcards String, @JvmSuppressWildcards String>
+    external fun methodWithMapTypeAlias(input: Map<String, String>) : Map<String, String>
 
 
-    external fun methodWithSetTypeAlias(input: Set<@JvmSuppressWildcards String>) : Set<@JvmSuppressWildcards String>
+    external fun methodWithSetTypeAlias(input: Set<String>) : Set<String>
 
-    var listProperty: List<@JvmSuppressWildcards Float>
+    var listProperty: List<Float>
         external get
         external set
 
-    var mapProperty: Map<@JvmSuppressWildcards Float, @JvmSuppressWildcards Double>
+    var mapProperty: Map<Float, Double>
         external get
         external set
 
-    var setProperty: Set<@JvmSuppressWildcards Float>
+    var setProperty: Set<Float>
         external get
         external set