Better array handling in 3.1 spec (#18313)

* better array detection in 3.1 spec

* fix

modules/openapi-generator/src/main/java/org/openapitools/codegen/DefaultCodegen.java

@@ -1092,7 +1092,7 @@ public class DefaultCodegen implements CodegenConfig {
                         addOneOfNameExtension(s, n);
                     }
                 } else if (ModelUtils.isArraySchema(s)) {
-                    Schema items = ((ArraySchema) s).getItems();
+                    Schema items = ModelUtils.getSchemaItems(s);
                     if (ModelUtils.isComposedSchema(items)) {
                         addOneOfNameExtension(items, nOneOf);
                         addOneOfInterfaceModel(items, nOneOf);
@@ -2065,8 +2065,7 @@ public class DefaultCodegen implements CodegenConfig {
             }
             return inner;
         } else if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(schema));
-            String inner = getSchemaType(getSchemaItems(arraySchema));
             String parentType;
             if (ModelUtils.isSet(schema)) {
                 parentType = "set";
@@ -2372,15 +2371,7 @@ public class DefaultCodegen implements CodegenConfig {
 
     }
 
-    protected Schema<?> getSchemaItems(ArraySchema schema) {
+
-        Schema<?> items = schema.getItems();
-        if (items == null) {
-            LOGGER.error("Undefined array inner type for `{}`. Default to String.", schema.getName());
-            items = new StringSchema().description("TODO default missing array inner type to string");
-            schema.setItems(items);
-        }
-        return items;
-    }
 
     protected Schema<?> getSchemaAdditionalProperties(Schema schema) {
         Schema<?> inner = ModelUtils.getAdditionalProperties(schema);
@@ -4190,8 +4181,7 @@ public class DefaultCodegen implements CodegenConfig {
 
             // handle inner property
             String itemName = getItemsName(p, name);
-            ArraySchema arraySchema = (ArraySchema) p;
+            Schema innerSchema = unaliasSchema(ModelUtils.getSchemaItems(p));
-            Schema innerSchema = unaliasSchema(getSchemaItems(arraySchema));
             CodegenProperty cp = fromProperty(itemName, innerSchema, false);
             updatePropertyForArray(property, cp);
         } else if (ModelUtils.isTypeObjectSchema(p)) {
@@ -4501,8 +4491,7 @@ public class DefaultCodegen implements CodegenConfig {
             CodegenProperty cm = fromProperty("response", responseSchema, false);
 
             if (ModelUtils.isArraySchema(responseSchema)) {
-                ArraySchema as = (ArraySchema) responseSchema;
+                CodegenProperty innerProperty = fromProperty("response", ModelUtils.getSchemaItems(responseSchema), false);
-                CodegenProperty innerProperty = fromProperty("response", getSchemaItems(as), false);
                 op.returnBaseType = innerProperty.baseType;
             } else if (ModelUtils.isMapSchema(responseSchema)) {
                 CodegenProperty innerProperty = fromProperty("response", ModelUtils.getAdditionalProperties(responseSchema), false);
@@ -5027,8 +5016,7 @@ public class DefaultCodegen implements CodegenConfig {
             r.isArray = true;
             r.containerType = cp.containerType;
             r.containerTypeMapped = typeMapping.get(cp.containerType);
-            ArraySchema as = (ArraySchema) responseSchema;
+            CodegenProperty items = fromProperty("response", ModelUtils.getSchemaItems(responseSchema), false);
-            CodegenProperty items = fromProperty("response", getSchemaItems(as), false);
             r.setItems(items);
             CodegenProperty innerCp = items;
 
@@ -5404,8 +5392,7 @@ public class DefaultCodegen implements CodegenConfig {
             }
             addVarsRequiredVarsAdditionalProps(parameterSchema, codegenParameter);
         } else if (ModelUtils.isArraySchema(parameterSchema)) {
-            final ArraySchema arraySchema = (ArraySchema) parameterSchema;
+            Schema inner = ModelUtils.getSchemaItems(parameterSchema);
-            Schema inner = getSchemaItems(arraySchema);
 
             collectionFormat = getCollectionFormat(parameter);
             // default to csv:
@@ -7291,7 +7278,7 @@ public class DefaultCodegen implements CodegenConfig {
         } else if (ModelUtils.isAnyType(ps)) {
             // any schema with no type set, composed schemas often do this
         } else if (ModelUtils.isArraySchema(ps)) {
-            Schema inner = getSchemaItems((ArraySchema) ps);
+            Schema inner = ModelUtils.getSchemaItems(ps);
             CodegenProperty arrayInnerProperty = fromProperty("inner", inner, false);
             codegenParameter.items = arrayInnerProperty;
             codegenParameter.mostInnerItems = arrayInnerProperty.mostInnerItems;
@@ -7572,11 +7559,10 @@ public class DefaultCodegen implements CodegenConfig {
         if (ModelUtils.isGenerateAliasAsModel(schema) && StringUtils.isNotBlank(name)) {
             this.addBodyModelSchema(codegenParameter, name, schema, imports, bodyParameterName, true);
         } else {
-            final ArraySchema arraySchema = (ArraySchema) schema;
+            Schema inner = ModelUtils.getSchemaItems(schema);
-            Schema inner = getSchemaItems(arraySchema);
+            CodegenProperty codegenProperty = fromProperty("property", schema, false);
-            CodegenProperty codegenProperty = fromProperty("property", arraySchema, false);
             if (codegenProperty == null) {
-                throw new RuntimeException("CodegenProperty cannot be null. arraySchema for debugging: " + arraySchema);
+                throw new RuntimeException("CodegenProperty cannot be null. arraySchema for debugging: " + schema);
             }
 
             imports.add(codegenProperty.baseType);
@@ -7609,7 +7595,7 @@ public class DefaultCodegen implements CodegenConfig {
 
             codegenParameter.items = codegenProperty.items;
             codegenParameter.mostInnerItems = codegenProperty.mostInnerItems;
-            codegenParameter.dataType = getTypeDeclaration(arraySchema);
+            codegenParameter.dataType = getTypeDeclaration(schema);
             codegenParameter.baseType = getSchemaType(inner);
             codegenParameter.isContainer = Boolean.TRUE;
             codegenParameter.isNullable = codegenProperty.isNullable;

modules/openapi-generator/src/main/java/org/openapitools/codegen/InlineModelResolver.java

@@ -338,10 +338,9 @@ public class InlineModelResolver {
             return;
         }
         // Check array items
-        if (schema instanceof ArraySchema) {
+        if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema array = (ArraySchema) schema;
+            Schema items = ModelUtils.getSchemaItems(schema);
-            Schema items = array.getItems();
+            if (items == null && schema.getPrefixItems() == null) {
-            if (items == null && array.getPrefixItems() == null) {
                 LOGGER.debug("Incorrect array schema with no items, prefixItems: {}", schema.toString());
                 return;
             }
@@ -357,7 +356,7 @@ public class InlineModelResolver {
 
             if (isModelNeeded(items)) {
                 // If this schema should be split into its own model, do so
-                array.setItems(this.makeSchemaInComponents(schemaName, items));
+                schema.setItems(this.makeSchemaInComponents(schemaName, items));
             }
         }
         // Check allOf, anyOf, oneOf for inline models
@@ -788,9 +787,8 @@ public class InlineModelResolver {
                     propsToUpdate.put(key, schema);
                     modelsToAdd.put(modelName, model);
                 }
-            } else if (property instanceof ArraySchema) {
+            } else if (ModelUtils.isArraySchema(property)) {
-                ArraySchema ap = (ArraySchema) property;
+                Schema inner = ModelUtils.getSchemaItems(property);
-                Schema inner = ap.getItems();
                 if (inner instanceof ObjectSchema) {
                     ObjectSchema op = (ObjectSchema) inner;
                     if (op.getProperties() != null && op.getProperties().size() > 0) {
@@ -801,12 +799,12 @@ public class InlineModelResolver {
                         if (existing != null) {
                             Schema schema = new Schema().$ref(existing);
                             schema.setRequired(op.getRequired());
-                            ap.setItems(schema);
+                            property.setItems(schema);
                         } else {
                             modelName = addSchemas(modelName, innerModel);
                             Schema schema = new Schema().$ref(modelName);
                             schema.setRequired(op.getRequired());
-                            ap.setItems(schema);
+                            property.setItems(schema);
                         }
                     }
                 } else if (ModelUtils.isComposedSchema(inner)) {
@@ -815,7 +813,7 @@ public class InlineModelResolver {
                     innerModelName = addSchemas(innerModelName, inner);
                     Schema schema = new Schema().$ref(innerModelName);
                     schema.setRequired(inner.getRequired());
-                    ap.setItems(schema);
+                    property.setItems(schema);
                 } else {
                     LOGGER.debug("Schema not yet handled in model resolver: {}", inner);
                 }

modules/openapi-generator/src/main/java/org/openapitools/codegen/OpenAPINormalizer.java

@@ -509,9 +509,10 @@ public class OpenAPINormalizer {
             visitedSchemas.add(schema);
         }
 
-        if (schema instanceof ArraySchema) { // array
+        if (ModelUtils.isArraySchema(schema)) { // array
-            normalizeArraySchema(schema);
+            Schema result = normalizeArraySchema(schema);
-            normalizeSchema(schema.getItems(), visitedSchemas);
+            normalizeSchema(result.getItems(), visitedSchemas);
+            return result;
         } else if (schema.getAdditionalProperties() instanceof Schema) { // map
             normalizeMapSchema(schema);
             normalizeSchema((Schema) schema.getAdditionalProperties(), visitedSchemas);
@@ -566,7 +567,8 @@ public class OpenAPINormalizer {
     }
 
     private Schema normalizeArraySchema(Schema schema) {
-        return processSetArraytoNullable(schema);
+        Schema result = processNormalize31Spec(schema, new HashSet<>());
+        return processSetArraytoNullable(result);
     }
 
     private Schema normalizeMapSchema(Schema schema) {
@@ -1222,7 +1224,7 @@ public class OpenAPINormalizer {
         // only one item (type) left
         if (schema.getTypes().size() == 1) {
             String type = String.valueOf(schema.getTypes().iterator().next());
-            if ("array".equals(type)) {
+            if (ModelUtils.isArraySchema(schema)) {
                 ArraySchema as = new ArraySchema();
                 as.setDescription(schema.getDescription());
                 as.setDefault(schema.getDefault());

modules/openapi-generator/src/main/java/org/openapitools/codegen/examples/ExampleGenerator.java

@@ -84,10 +84,9 @@ public class ExampleGenerator {
         }
 
         if (ModelUtils.isArraySchema(responseSchema)) { // array of schema
-            ArraySchema as = (ArraySchema) responseSchema;
+            if (ModelUtils.getSchemaItems(responseSchema) != null) { // array of primitive types
-            if (as.getItems() != null) { // array of primitive types
                 return generate((Map<String, Object>) responseSchema.getExample(),
-                        new ArrayList<>(producesInfo), as);
+                        new ArrayList<>(producesInfo), responseSchema);
             } else {
                 // TODO log warning message as such case is not handled at the moment
                 return null;
@@ -248,9 +247,9 @@ public class ExampleGenerator {
             }
             return Boolean.TRUE;
         } else if (ModelUtils.isArraySchema(property)) {
-            Schema innerType = ((ArraySchema) property).getItems();
+            Schema innerType = ModelUtils.getSchemaItems(property);
             if (innerType != null) {
-                int arrayLength = null == ((ArraySchema) property).getMaxItems() ? 2 : ((ArraySchema) property).getMaxItems();
+                int arrayLength = null == property.getMaxItems() ? 2 :  property.getMaxItems();
                 // avoid memory issues by limiting to max. 5 items
                 arrayLength = Math.min(arrayLength, 5);
                 Object[] objectProperties = new Object[arrayLength];

modules/openapi-generator/src/main/java/org/openapitools/codegen/examples/XmlExampleGenerator.java

@@ -128,8 +128,7 @@ public class XmlExampleGenerator {
         StringBuilder sb = new StringBuilder();
 
         if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema as = (ArraySchema) schema;
+            Schema inner = ModelUtils.getSchemaItems(schema);
-            Schema inner = as.getItems();
             boolean wrapped = false;
             if (schema.getXml() != null && schema.getXml().getWrapped() != null && schema.getXml().getWrapped()) {
                 wrapped = true;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractAdaCodegen.java

@@ -532,8 +532,7 @@ abstract public class AbstractAdaCodegen extends DefaultCodegen implements Codeg
         }
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             String itemType = getTypeDeclaration(inner);
             if (itemType.startsWith("OpenAPI.")) {
                 return itemType + "_Vector";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractApexCodegen.java

@@ -188,10 +188,9 @@ public abstract class AbstractApexCodegen extends DefaultCodegen implements Code
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             if (inner == null) {
-                LOGGER.warn("{}(array property) does not have a proper inner type defined", ap.getName());
+                LOGGER.warn("{}(array property) does not have a proper inner type defined", p.getName());
                 // TODO maybe better defaulting to StringProperty than returning null
                 return null;
             }
@@ -220,13 +219,12 @@ public abstract class AbstractApexCodegen extends DefaultCodegen implements Code
     @Override
     public String toDefaultValue(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            final ArraySchema ap = (ArraySchema) p;
             final String pattern = "new ArrayList<%s>()";
-            if (ap.getItems() == null) {
+            if (ModelUtils.getSchemaItems(p) == null) {
                 return null;
             }
 
-            return String.format(Locale.ROOT, pattern, getTypeDeclaration(ap.getItems()));
+            return String.format(Locale.ROOT, pattern, getTypeDeclaration(ModelUtils.getSchemaItems(p)));
         } else if (ModelUtils.isMapSchema(p)) {
             final MapSchema ap = (MapSchema) p;
             final String pattern = "new HashMap<%s>()";
@@ -318,7 +316,7 @@ public abstract class AbstractApexCodegen extends DefaultCodegen implements Code
 
         if (ModelUtils.isArraySchema(p)) {
             example = "new " + getTypeDeclaration(p) + "{" + toExampleValue(
-                    ((ArraySchema) p).getItems()) + "}";
+                    ModelUtils.getSchemaItems(p)) + "}";
         } else if (ModelUtils.isBooleanSchema(p)) {
             example = String.valueOf(!"false".equals(example));
         } else if (ModelUtils.isByteArraySchema(p)) {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractCSharpCodegen.java

@@ -1433,12 +1433,12 @@ public abstract class AbstractCSharpCodegen extends DefaultCodegen implements Co
      * @param arr The input array property
      * @return The type declaration when the type is an array of arrays.
      */
-    private String getArrayTypeDeclaration(ArraySchema arr) {
+    private String getArrayTypeDeclaration(Schema arr) {
         // TODO: collection type here should be fully qualified namespace to avoid model conflicts
         // This supports arrays of arrays.
         String arrayType = typeMapping.get("array");
         StringBuilder instantiationType = new StringBuilder(arrayType);
-        Schema items = arr.getItems();
+        Schema items = ModelUtils.getSchemaItems(arr);
         String nestedType = getTypeDeclaration(items);
         // TODO: We may want to differentiate here between generics and primitive arrays.
         instantiationType.append("<").append(nestedType).append(">");
@@ -1448,7 +1448,7 @@ public abstract class AbstractCSharpCodegen extends DefaultCodegen implements Co
     @Override
     public String toInstantiationType(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            return getArrayTypeDeclaration((ArraySchema) p);
+            return getArrayTypeDeclaration(p);
         }
         return super.toInstantiationType(p);
     }
@@ -1456,7 +1456,7 @@ public abstract class AbstractCSharpCodegen extends DefaultCodegen implements Co
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            return getArrayTypeDeclaration((ArraySchema) p);
+            return getArrayTypeDeclaration(p);
         } else if (ModelUtils.isMapSchema(p)) {
             // Should we also support maps of maps?
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractDartCodegen.java

@@ -512,7 +512,7 @@ public abstract class AbstractDartCodegen extends DefaultCodegen {
         Schema<?> schema = unaliasSchema(p);
         Schema<?> target = ModelUtils.isGenerateAliasAsModel() ? p : schema;
         if (ModelUtils.isArraySchema(target)) {
-            Schema<?> items = getSchemaItems((ArraySchema) schema);
+            Schema<?> items = ModelUtils.getSchemaItems(schema);
             return getSchemaType(target) + "<" + getTypeDeclaration(items) + ">";
         }
         if (ModelUtils.isMapSchema(target)) {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractEiffelCodegen.java

@@ -293,8 +293,7 @@ public abstract class AbstractEiffelCodegen extends DefaultCodegen implements Co
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "LIST [" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -578,8 +577,7 @@ public abstract class AbstractEiffelCodegen extends DefaultCodegen implements Co
 //            String inner = toModelName(getSchemaType(additionalProperties2));
 //            return instantiationTypes.get("map") + " [" + inner + "]";
 //        } else if (ModelUtils.isArraySchema(p)) {
-//            ArraySchema ap = (ArraySchema) p;
+//            String inner = toModelName(getSchemaType(ModelUtils.getSchemaItems(p)));
-//            String inner = toModelName(getSchemaType(ap.getItems()));
 //            return instantiationTypes.get("array") + " [" + inner + "]";
 //        } else {
 //            return null;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractFSharpCodegen.java

@@ -855,12 +855,12 @@ public abstract class AbstractFSharpCodegen extends DefaultCodegen implements Co
      * @param arr The input array property
      * @return The type declaration when the type is an array of arrays.
      */
-    private String getArrayTypeDeclaration(ArraySchema arr) {
+    private String getArrayTypeDeclaration(Schema arr) {
         // TODO: collection type here should be fully qualified namespace to avoid model conflicts
         // This supports arrays of arrays.
         String arrayType = typeMapping.get("array");
         StringBuilder instantiationType = new StringBuilder(arrayType);
-        Schema items = arr.getItems();
+        Schema items = ModelUtils.getSchemaItems(arr);
         String nestedType = getTypeDeclaration(items);
         // TODO: We may want to differentiate here between generics and primitive arrays.
         return nestedType + "[]";
@@ -869,7 +869,7 @@ public abstract class AbstractFSharpCodegen extends DefaultCodegen implements Co
     @Override
     public String toInstantiationType(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            return getArrayTypeDeclaration((ArraySchema) p);
+            return getArrayTypeDeclaration(p);
         }
         return super.toInstantiationType(p);
     }
@@ -877,7 +877,7 @@ public abstract class AbstractFSharpCodegen extends DefaultCodegen implements Co
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            return getArrayTypeDeclaration((ArraySchema) p);
+            return getArrayTypeDeclaration(p);
         } else if (ModelUtils.isMapSchema(p)) {
             // Should we also support maps of maps?
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractGoCodegen.java

@@ -360,8 +360,7 @@ public abstract class AbstractGoCodegen extends DefaultCodegen implements Codege
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             // In OAS 3.0.x, the array "items" attribute is required.
             // In OAS >= 3.1, the array "items" attribute is optional such that the OAS
             // specification is aligned with the JSON schema specification.

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractGraphQLCodegen.java

@@ -273,8 +273,7 @@ public abstract class AbstractGraphQLCodegen extends DefaultCodegen implements C
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Object ap = p.getAdditionalProperties();

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJavaCodegen.java

@@ -946,7 +946,7 @@ public abstract class AbstractJavaCodegen extends DefaultCodegen implements Code
         Schema<?> schema = unaliasSchema(p);
         Schema<?> target = ModelUtils.isGenerateAliasAsModel() ? p : schema;
         if (ModelUtils.isArraySchema(target)) {
-            Schema<?> items = getSchemaItems((ArraySchema) schema);
+            Schema<?> items = ModelUtils.getSchemaItems(schema);
             return getSchemaType(target) + "<" + getBeanValidation(items) + getTypeDeclaration(items) + ">";
         } else if (ModelUtils.isMapSchema(target)) {
             // Note: ModelUtils.isMapSchema(p) returns true when p is a composed schema that also defines

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractJuliaCodegen.java

@@ -346,8 +346,7 @@ public abstract class AbstractJuliaCodegen extends DefaultCodegen {
     @Override
     public String getTypeDeclaration(Schema schema) {
         if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema ap = (ArraySchema) schema;
+            Schema inner = ModelUtils.getSchemaItems(schema);
-            Schema inner = ap.getItems();
             return getSchemaType(schema) + "{" + getTypeDeclaration(inner) + "}";
         } else if (ModelUtils.isSet(schema)) {
             Schema inner = ModelUtils.getAdditionalProperties(schema);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractKotlinCodegen.java

@@ -359,7 +359,7 @@ public abstract class AbstractKotlinCodegen extends DefaultCodegen implements Co
         Schema<?> schema = unaliasSchema(p);
         Schema<?> target = ModelUtils.isGenerateAliasAsModel() ? p : schema;
         if (ModelUtils.isArraySchema(target)) {
-            Schema<?> items = getSchemaItems((ArraySchema) schema);
+            Schema<?> items = ModelUtils.getSchemaItems( schema);
             return getSchemaType(target) + "<" + getTypeDeclaration(items) + ">";
         } else if (ModelUtils.isMapSchema(target)) {
             // Note: ModelUtils.isMapSchema(p) returns true when p is a composed schema that also defines
@@ -1104,7 +1104,7 @@ public abstract class AbstractKotlinCodegen extends DefaultCodegen implements Co
             }
 
             StringBuilder defaultContent = new StringBuilder();
-            Schema<?> itemsSchema = getSchemaItems((ArraySchema) schema);
+            Schema<?> itemsSchema = ModelUtils.getSchemaItems(schema);
             _default.elements().forEachRemaining((element) -> {
                 String defaultValue = element.asText();
                 if (defaultValue != null) {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPhpCodegen.java

@@ -355,11 +355,10 @@ public abstract class AbstractPhpCodegen extends DefaultCodegen implements Codeg
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             if (inner == null) {
                 LOGGER.warn("{}(array property) does not have a proper inner type defined.Default to string",
-                        ap.getName());
+                        p.getName());
                 inner = new StringSchema().description("TODO default missing array inner type to string");
             }
             return getTypeDeclaration(inner) + "[]";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPythonCodegen.java

@@ -491,8 +491,7 @@ public abstract class AbstractPythonCodegen extends DefaultCodegen implements Co
             if (StringUtils.isNotBlank(schema.getTitle()) && !"null".equals(schema.getTitle())) {
                 includedSchemas.add(schema);
             }
-            ArraySchema arrayschema = (ArraySchema) schema;
+            example = "[\n" + indentationString + toExampleValueRecursive(ModelUtils.getSchemaItems(schema), includedSchemas, indentation + 1) + "\n" + indentationString + "]";
-            example = "[\n" + indentationString + toExampleValueRecursive(arrayschema.getItems(), includedSchemas, indentation + 1) + "\n" + indentationString + "]";
         } else if (ModelUtils.isMapSchema(schema)) {
             if (StringUtils.isNotBlank(schema.getTitle()) && !"null".equals(schema.getTitle())) {
                 includedSchemas.add(schema);
@@ -693,8 +692,7 @@ public abstract class AbstractPythonCodegen extends DefaultCodegen implements Co
         p = ModelUtils.unaliasSchema(openAPI, p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getCollectionItemTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPythonConnexionServerCodegen.java

@@ -351,8 +351,7 @@ public abstract class AbstractPythonConnexionServerCodegen extends AbstractPytho
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractPythonPydanticV1Codegen.java

@@ -454,8 +454,7 @@ public abstract class AbstractPythonPydanticV1Codegen extends DefaultCodegen imp
             if (StringUtils.isNotBlank(schema.getTitle()) && !"null".equals(schema.getTitle())) {
                 includedSchemas.add(schema);
             }
-            ArraySchema arrayschema = (ArraySchema) schema;
+            example = "[\n" + indentationString + toExampleValueRecursive(ModelUtils.getSchemaItems(schema), includedSchemas, indentation + 1) + "\n" + indentationString + "]";
-            example = "[\n" + indentationString + toExampleValueRecursive(arrayschema.getItems(), includedSchemas, indentation + 1) + "\n" + indentationString + "]";
         } else if (ModelUtils.isMapSchema(schema)) {
             if (StringUtils.isNotBlank(schema.getTitle()) && !"null".equals(schema.getTitle())) {
                 includedSchemas.add(schema);
@@ -656,8 +655,7 @@ public abstract class AbstractPythonPydanticV1Codegen extends DefaultCodegen imp
         p = ModelUtils.unaliasSchema(openAPI, p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractRubyCodegen.java

@@ -119,7 +119,7 @@ abstract public class AbstractRubyCodegen extends DefaultCodegen implements Code
     @Override
     public String getTypeDeclaration(Schema schema) {
         if (ModelUtils.isArraySchema(schema)) {
-            Schema inner = ((ArraySchema) schema).getItems();
+            Schema inner = ModelUtils.getSchemaItems(schema);
             return getSchemaType(schema) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(schema)) {
             Schema inner = ModelUtils.getAdditionalProperties(schema);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractRustCodegen.java

@@ -236,8 +236,7 @@ public abstract class AbstractRustCodegen extends DefaultCodegen implements Code
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             String innerType = getTypeDeclaration(inner);
             return typeMapping.get("array") + "<" + innerType + ">";
         } else if (ModelUtils.isMapSchema(p)) {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java

@@ -371,7 +371,7 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
         Schema<?> schema = unaliasSchema(p);
         Schema<?> target = ModelUtils.isGenerateAliasAsModel() ? p : schema;
         if (ModelUtils.isArraySchema(target)) {
-            Schema<?> items = getSchemaItems((ArraySchema) schema);
+            Schema<?> items = ModelUtils.getSchemaItems(schema);
             return getSchemaType(target) + "[" + getTypeDeclaration(items) + "]";
         } else if (ModelUtils.isMapSchema(target)) {
             Schema<?> inner = ModelUtils.getAdditionalProperties(target);
@@ -404,9 +404,8 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return instantiationTypes.get("map") + "[String, " + inner + "]";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            return (ModelUtils.isSet(p) ? instantiationTypes.get("set") : instantiationTypes.get("array")) + "[" + inner + "]";
-            return (ModelUtils.isSet(ap) ? instantiationTypes.get("set") : instantiationTypes.get("array")) + "[" + inner + "]";
         } else {
             return null;
         }
@@ -433,10 +432,9 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "new HashMap[String, " + inner + "]() ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             String genericType;
-            if (ModelUtils.isSet(ap)) {
+            if (ModelUtils.isSet(p)) {
                 genericType = instantiationTypes.get("set");
             } else {
                 genericType = instantiationTypes.get("array");
@@ -475,8 +473,7 @@ public abstract class AbstractScalaCodegen extends DefaultCodegen {
     public CodegenProperty fromProperty(String name, Schema p, boolean required) {
         CodegenProperty prop = super.fromProperty(name, p, required);
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema as = (ArraySchema) p;
+            if (ModelUtils.isSet(p)) {
-            if (ModelUtils.isSet(as)) {
                 prop.containerType = "set";
             }
         }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractTypeScriptClientCodegen.java

@@ -624,7 +624,7 @@ public abstract class AbstractTypeScriptClientCodegen extends DefaultCodegen imp
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            Schema<?> items = getSchemaItems((ArraySchema) p);
+            Schema<?> items = ModelUtils.getSchemaItems(p);
             return getSchemaType(p) + "<" + getTypeDeclaration(unaliasSchema(items)) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema<?> inner = getSchemaAdditionalProperties(p);
@@ -647,8 +647,7 @@ public abstract class AbstractTypeScriptClientCodegen extends DefaultCodegen imp
         // handle enums of various data types
         Schema inner;
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema mp1 = (ArraySchema) p;
+            inner = ModelUtils.getSchemaItems(p);
-            inner = mp1.getItems();
             return this.getSchemaType(p) + "<" + this.getParameterDataType(parameter, inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             inner = ModelUtils.getAdditionalProperties(p);
@@ -1177,8 +1176,7 @@ public abstract class AbstractTypeScriptClientCodegen extends DefaultCodegen imp
         return filteredSchemas.stream().map(schema -> {
             String schemaType = getSchemaType(schema);
             if (ModelUtils.isArraySchema(schema)) {
-                ArraySchema ap = (ArraySchema) schema;
+                Schema inner = ModelUtils.getSchemaItems(schema);
-                Schema inner = ap.getItems();
                 schemaType = schemaType + "<" + getSchemaType(inner) + ">";
             }
             return schemaType;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AndroidClientCodegen.java

@@ -221,8 +221,7 @@ public class AndroidClientCodegen extends DefaultCodegen implements CodegenConfi
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ApexClientCodegen.java

@@ -223,7 +223,7 @@ public class ApexClientCodegen extends AbstractApexCodegen {
     public String toDefaultValue(Schema p) {
         String out = null;
         if (ModelUtils.isArraySchema(p)) {
-            Schema inner = ((ArraySchema) p).getItems();
+            Schema inner = ModelUtils.getSchemaItems(p);
             out = String.format(
                     Locale.ROOT,
                     "new List<%s>()",

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/BashClientCodegen.java

@@ -429,8 +429,7 @@ public class BashClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpClientCodegen.java

@@ -1515,8 +1515,7 @@ public class CSharpClientCodegen extends AbstractCSharpCodegen {
             }
             return instantiationTypes.get("map") + "<String, " + inner + ">";
         } else if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(schema));
-            String inner = getSchemaType(arraySchema.getItems());
             return instantiationTypes.get("array") + "<" + inner + ">";
         } else {
             return null;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CSharpReducedClientCodegen.java

@@ -1091,8 +1091,7 @@ public class CSharpReducedClientCodegen extends AbstractCSharpCodegen {
             }
             return instantiationTypes.get("map") + "<String, " + inner + ">";
         } else if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(schema));
-            String inner = getSchemaType(arraySchema.getItems());
             return instantiationTypes.get("array") + "<" + inner + ">";
         } else {
             return null;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ClojureClientCodegen.java

@@ -165,10 +165,8 @@ public class ClojureClientCodegen extends DefaultCodegen implements CodegenConfi
 
     @Override
     public String getTypeDeclaration(Schema p) {
-        if (p instanceof ArraySchema) {
+        if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
-
             return "(s/coll-of " + getTypeDeclaration(inner) + ")";
         } else if (ModelUtils.isMapSchema(p)) {
             Object ap = p.getAdditionalProperties();

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ConfluenceWikiCodegen.java

@@ -108,8 +108,7 @@ public class ConfluenceWikiCodegen extends DefaultCodegen implements CodegenConf
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppPistacheServerCodegen.java

@@ -381,8 +381,7 @@ public class CppPistacheServerCodegen extends AbstractCppCodegen {
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         }
         if (ModelUtils.isMapSchema(p)) {
@@ -474,8 +473,7 @@ public class CppPistacheServerCodegen extends AbstractCppCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "std::map<std::string, " + inner + ">()";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             if (!languageSpecificPrimitives.contains(inner)) {
                 inner = "std::shared_ptr<" + inner + ">";
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppQtAbstractCodegen.java

@@ -189,8 +189,7 @@ public abstract class CppQtAbstractCodegen extends AbstractCppCodegen implements
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -232,8 +231,7 @@ public abstract class CppQtAbstractCodegen extends AbstractCppCodegen implements
             Schema inner = ModelUtils.getAdditionalProperties(p);
             return "QMap<QString, " + getTypeDeclaration(inner) + ">()";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "QList<" + getTypeDeclaration(inner) + ">()";
         } else if (ModelUtils.isStringSchema(p)) {
             return "QString(\"\")";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestSdkClientCodegen.java

@@ -367,8 +367,7 @@ public class CppRestSdkClientCodegen extends AbstractCppCodegen {
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -407,8 +406,7 @@ public class CppRestSdkClientCodegen extends AbstractCppCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "std::map<utility::string_t, " + inner + ">()";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             if (!languageSpecificPrimitives.contains(inner)) {
                 inner = "std::shared_ptr<" + inner + ">";
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerCodegen.java

@@ -379,8 +379,7 @@ public class CppRestbedServerCodegen extends AbstractCppCodegen {
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -469,12 +468,10 @@ public class CppRestbedServerCodegen extends AbstractCppCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "std::map<std::string, " + inner + ">()";
         } else if (ModelUtils.isSet(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             return "std::set<" + inner + ">()";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             return "std::vector<" + inner + ">()";
         } else if (ModelUtils.isModel(p)) {
             String modelName = getTypeDeclaration(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppRestbedServerDeprecatedCodegen.java

@@ -351,8 +351,7 @@ public class CppRestbedServerDeprecatedCodegen extends AbstractCppCodegen {
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -433,8 +432,7 @@ public class CppRestbedServerDeprecatedCodegen extends AbstractCppCodegen {
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "std::map<std::string, " + inner + ">()";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             if (!languageSpecificPrimitives.contains(inner)) {
                 inner = "std::shared_ptr<" + inner + ">";
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CppUE4ClientCodegen.java

@@ -416,8 +416,7 @@ public class CppUE4ClientCodegen extends AbstractCppCodegen {
         String openAPIType = getSchemaType(p);
 
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            return getSchemaType(p) + "<" + getTypeDeclaration(ModelUtils.getSchemaItems(p)) + ">";
-            return getSchemaType(p) + "<" + getTypeDeclaration(ap.getItems()) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             return getSchemaType(p) + "<FString, " + getTypeDeclaration(ModelUtils.getAdditionalProperties(p)) + ">";
         }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/CrystalClientCodegen.java

@@ -814,7 +814,7 @@ public class CrystalClientCodegen extends DefaultCodegen {
     @Override
     public String getTypeDeclaration(Schema schema) {
         if (ModelUtils.isArraySchema(schema)) {
-            Schema inner = ((ArraySchema) schema).getItems();
+            Schema inner = ModelUtils.getSchemaItems(schema);
             return getSchemaType(schema) + "(" + getTypeDeclaration(inner) + ")";
         } else if (ModelUtils.isMapSchema(schema)) {
             Schema inner = ModelUtils.getAdditionalProperties(schema);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElixirClientCodegen.java

@@ -557,8 +557,7 @@ public class ElixirClientCodegen extends DefaultCodegen {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ElmClientCodegen.java

@@ -244,8 +244,7 @@ public class ElmClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String toInstantiationType(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             return instantiationTypes.get("array") + " " + inner;
         } else {
             return null;
@@ -464,8 +463,7 @@ public class ElmClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getTypeDeclaration(inner);
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ErlangProperCodegen.java

@@ -141,7 +141,7 @@ public class ErlangProperCodegen extends DefaultCodegen implements CodegenConfig
     public CodegenModel fromModel(String name, Schema model) {
         CodegenModel cm = super.fromModel(name, model);
         if(ModelUtils.isArraySchema(model)) {
-            return new CodegenArrayModel(cm, (ArraySchema) model);
+            return new CodegenArrayModel(cm, model);
         } else {
             return cm;
         }
@@ -156,12 +156,9 @@ public class ErlangProperCodegen extends DefaultCodegen implements CodegenConfig
     public String getTypeDeclaration(Schema schema) {
         String typeDeclaration = super.getSchemaType(schema);
         if(ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            String complexType = getSchemaType(ModelUtils.getSchemaItems(schema));
-            String complexType = getSchemaType(arraySchema.getItems());
-
             StringBuilder sb = new StringBuilder("list(");
             sb.append(complexType);
-
             return sb.append(")").toString();
         } else if (typeMapping.containsKey(typeDeclaration)) {
             return typeMapping.get(typeDeclaration);
@@ -174,8 +171,7 @@ public class ErlangProperCodegen extends DefaultCodegen implements CodegenConfig
     public String getSchemaType(Schema schema) {
         String schemaType = super.getSchemaType(schema);
         if(ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            String complexType = getSchemaType(ModelUtils.getSchemaItems(schema));
-            String complexType = getSchemaType(arraySchema.getItems());
 
             StringBuilder sb = new StringBuilder("list(");
             sb.append(complexType);
@@ -446,7 +442,7 @@ public class ErlangProperCodegen extends DefaultCodegen implements CodegenConfig
         Integer minItems;
         Integer maxItems;
 
-        public CodegenArrayModel(CodegenModel cm, ArraySchema schema) {
+        public CodegenArrayModel(CodegenModel cm, Schema schema) {
             super();
 
             // Copy all fields of CodegenModel

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GraphQLNodeJSExpressServerCodegen.java

@@ -124,8 +124,7 @@ public class GraphQLNodeJSExpressServerCodegen extends AbstractGraphQLCodegen im
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
 
             // IMPORTANT NOTE we add the braces within template because there we have the possibility to differentiate
             // between some specific types for GraphQL:

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellHttpClientCodegen.java

@@ -653,8 +653,7 @@ public class HaskellHttpClientCodegen extends DefaultCodegen implements CodegenC
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -687,8 +686,7 @@ public class HaskellHttpClientCodegen extends DefaultCodegen implements CodegenC
             String inner = getSchemaType(additionalProperties2);
             return "(Map.Map Text " + inner + ")";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            return getSchemaType(ModelUtils.getSchemaItems(p));
-            return getSchemaType(ap.getItems());
         } else {
             return null;
         }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellServantCodegen.java

@@ -372,8 +372,7 @@ public class HaskellServantCodegen extends DefaultCodegen implements CodegenConf
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -419,8 +418,7 @@ public class HaskellServantCodegen extends DefaultCodegen implements CodegenConf
             String inner = getSchemaType(additionalProperties2);
             return "(Map.Map Text " + inner + ")";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             // Return only the inner type; the wrapping with QueryList is done
             // somewhere else, where we have access to the collection format.
             return inner;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/HaskellYesodServerCodegen.java

@@ -295,8 +295,7 @@ public class HaskellYesodServerCodegen extends DefaultCodegen implements Codegen
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -342,8 +341,7 @@ public class HaskellYesodServerCodegen extends DefaultCodegen implements Codegen
             String inner = getSchemaType(additionalProperties2);
             return "(Map.Map Text " + inner + ")";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             // Return only the inner type; the wrapping with QueryList is done
             // somewhere else, where we have access to the collection format.
             return inner;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JMeterClientCodegen.java

@@ -210,8 +210,7 @@ public class JMeterClientCodegen extends DefaultCodegen implements CodegenConfig
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptApolloClientCodegen.java

@@ -610,8 +610,7 @@ public class JavascriptApolloClientCodegen extends DefaultCodegen implements Cod
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -872,9 +871,9 @@ public class JavascriptApolloClientCodegen extends DefaultCodegen implements Cod
             codegenModel = JavascriptApolloClientCodegen.reconcileInlineEnums(codegenModel, parentCodegenModel);
         }
         if (ModelUtils.isArraySchema(model)) {
-            ArraySchema am = (ArraySchema) model;
+            Schema inner = ModelUtils.getSchemaItems(model);
-            if (codegenModel != null && am.getItems() != null) {
+            if (codegenModel != null && inner != null) {
-                String itemType = getSchemaType(am.getItems());
+                String itemType = getSchemaType(inner);
                 codegenModel.vendorExtensions.put("x-is-array", true);
                 codegenModel.vendorExtensions.put("x-item-type", itemType);
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClientCodegen.java

@@ -610,8 +610,7 @@ public class JavascriptClientCodegen extends DefaultCodegen implements CodegenCo
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -874,9 +873,8 @@ public class JavascriptClientCodegen extends DefaultCodegen implements CodegenCo
             }
         }
         if (ModelUtils.isArraySchema(model)) {
-            ArraySchema am = (ArraySchema) model;
+            if (codegenModel != null && ModelUtils.getSchemaItems(model) != null) {
-            if (codegenModel != null && am.getItems() != null) {
+                String itemType = getSchemaType(ModelUtils.getSchemaItems(model));
-                String itemType = getSchemaType(am.getItems());
                 codegenModel.vendorExtensions.put("x-is-array", true);
                 codegenModel.vendorExtensions.put("x-item-type", itemType);
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/JavascriptClosureAngularClientCodegen.java

@@ -225,8 +225,7 @@ public class JavascriptClosureAngularClientCodegen extends DefaultCodegen implem
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "<!" + getTypeDeclaration(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/LuaClientCodegen.java

@@ -383,8 +383,7 @@ public class LuaClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getTypeDeclaration(inner);
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/N4jsClientCodegen.java

@@ -513,7 +513,7 @@ public class N4jsClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            Schema<?> items = getSchemaItems((ArraySchema) p);
+            Schema<?> items = ModelUtils.getSchemaItems(p);
             return getTypeDeclaration(unaliasSchema(items)) + "[]";
         } else if (ModelUtils.isMapSchema(p)) {
             return "~Object+";
@@ -544,8 +544,7 @@ public class N4jsClientCodegen extends DefaultCodegen implements CodegenConfig {
     protected String getParameterDataType(Parameter parameter, Schema p) {
         // handle enums of various data types
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema mp1 = (ArraySchema) p;
+            Schema<?> inner = ModelUtils.getSchemaItems(p);
-            Schema<?> inner = mp1.getItems();
             return getParameterDataType(parameter, inner) + "[]";
         } else if (ModelUtils.isMapSchema(p)) {
             return "~Object+";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/NimClientCodegen.java

@@ -275,8 +275,7 @@ public class NimClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             if (inner == null) {
                 return null;
             }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/OCamlClientCodegen.java

@@ -279,8 +279,8 @@ public class OCamlClientCodegen extends DefaultCodegen implements CodegenConfig
     }
 
     private void collectEnumSchemas(String parentName, String sName, Schema schema) {
-        if (schema instanceof ArraySchema) {
+        if (ModelUtils.isArraySchema(schema)) {
-            collectEnumSchemas(parentName, sName, ((ArraySchema) schema).getItems());
+            collectEnumSchemas(parentName, sName, ModelUtils.getSchemaItems(schema));
         } else if (schema instanceof MapSchema && schema.getAdditionalProperties() instanceof Schema) {
             collectEnumSchemas(parentName, sName, (Schema) schema.getAdditionalProperties());
         } else if (isEnumSchema(schema)) {
@@ -317,11 +317,10 @@ public class OCamlClientCodegen extends DefaultCodegen implements CodegenConfig
                 collectEnumSchemas(pName, (Schema) schema.getAdditionalProperties());
             }
 
-            if (schema instanceof ArraySchema) {
+            if (ModelUtils.isArraySchema(schema)) {
-                ArraySchema s = (ArraySchema) schema;
+                if (ModelUtils.getSchemaItems(schema) != null) {
-                if (s.getItems() != null) {
                     String pName = parentName != null ? parentName + "_" + sName : sName;
-                    collectEnumSchemas(pName, s.getItems());
+                    collectEnumSchemas(pName, ModelUtils.getSchemaItems(schema));
                 }
             }
         }
@@ -581,11 +580,10 @@ public class OCamlClientCodegen extends DefaultCodegen implements CodegenConfig
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             if (inner == null) {
                 LOGGER.warn("{}(array property) does not have a proper inner type defined.Default to string",
-                        ap.getName());
+                        p.getName());
                 inner = new StringSchema().description("TODO default missing array inner type to string");
             }
             return getTypeDeclaration(inner) + " list";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ObjcClientCodegen.java

@@ -370,8 +370,7 @@ public class ObjcClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             String innerTypeDeclaration = getTypeDeclaration(inner);
             if (innerTypeDeclaration.endsWith("*")) {
                 innerTypeDeclaration = innerTypeDeclaration.substring(0, innerTypeDeclaration.length() - 1);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PerlClientCodegen.java

@@ -261,8 +261,7 @@ public class PerlClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpDataTransferClientCodegen.java

@@ -271,7 +271,7 @@ public class PhpDataTransferClientCodegen extends AbstractPhpCodegen {
         Schema parameterSchema = ModelUtils.getReferencedSchema(openAPI, parameter.getSchema());
         // array
         if (ModelUtils.isArraySchema(parameterSchema)) {
-            Schema itemSchema = ((ArraySchema) parameterSchema).getItems();
+            Schema itemSchema = ModelUtils.getSchemaItems(parameterSchema);
             ArraySchema arraySchema = new ArraySchema();
             arraySchema.setMinItems(parameterSchema.getMinItems());
             arraySchema.setMaxItems(parameterSchema.getMaxItems());
@@ -419,7 +419,7 @@ public class PhpDataTransferClientCodegen extends AbstractPhpCodegen {
                 }
             } else if (ModelUtils.isArraySchema(schema)) {
                 //Recursively process schema of array items
-                generateContainerSchemas(openAPI, visitedSchemas, ((ArraySchema) schema).getItems());
+                generateContainerSchemas(openAPI, visitedSchemas, ModelUtils.getSchemaItems(schema));
                 isContainer = Boolean.TRUE;
             } else if (ModelUtils.isMapSchema(schema)) {
                 //Recursively process schema of map items

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpMezzioPathHandlerServerCodegen.java

@@ -248,7 +248,7 @@ public class PhpMezzioPathHandlerServerCodegen extends AbstractPhpCodegen {
             Schema parameterSchema = ModelUtils.getReferencedSchema(openAPI, queryParameter.getSchema());
             // array
             if (ModelUtils.isArraySchema(parameterSchema)) {
-                Schema itemSchema = ((ArraySchema) parameterSchema).getItems();
+                Schema itemSchema = ModelUtils.getSchemaItems(parameterSchema);
                 ArraySchema arraySchema = new ArraySchema();
                 arraySchema.setMinItems(parameterSchema.getMinItems());
                 arraySchema.setMaxItems(parameterSchema.getMaxItems());
@@ -397,7 +397,7 @@ public class PhpMezzioPathHandlerServerCodegen extends AbstractPhpCodegen {
                 }
             } else if (ModelUtils.isArraySchema(schema)) {
                 //Recursively process schema of array items
-                generateContainerSchemas(openAPI, visitedSchemas, ((ArraySchema) schema).getItems());
+                generateContainerSchemas(openAPI, visitedSchemas, ModelUtils.getSchemaItems(schema));
                 isContainer = Boolean.TRUE;
             } else if (ModelUtils.isMapSchema(schema)) {
                 //Recursively process schema of map items

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSilexServerCodegen.java

@@ -175,8 +175,7 @@ public class PhpSilexServerCodegen extends DefaultCodegen implements CodegenConf
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PhpSymfonyServerCodegen.java

@@ -538,8 +538,7 @@ public class PhpSymfonyServerCodegen extends AbstractPhpCodegen implements Codeg
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getTypeDeclaration(inner);
         }
 

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PowerShellClientCodegen.java

@@ -998,8 +998,7 @@ public class PowerShellClientCodegen extends DefaultCodegen implements CodegenCo
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getTypeDeclaration(inner) + "[]";
         } else if (ModelUtils.isMapSchema(p)) {
             return "System.Collections.Hashtable";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ProtobufSchemaCodegen.java

@@ -608,8 +608,7 @@ public class ProtobufSchemaCodegen extends DefaultCodegen implements CodegenConf
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/PythonFastAPIServerCodegen.java

@@ -223,8 +223,7 @@ public class PythonFastAPIServerCodegen extends AbstractPythonCodegen {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RClientCodegen.java

@@ -535,8 +535,7 @@ public class RClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RustAxumServerCodegen.java

@@ -682,8 +682,7 @@ public class RustAxumServerCodegen extends AbstractRustCodegen implements Codege
     @Override
     public String toInstantiationType(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return instantiationTypes.get("array") + "<" + getSchemaType(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RustServerCodegen.java

@@ -981,8 +981,7 @@ public class RustServerCodegen extends AbstractRustCodegen implements CodegenCon
     @Override
     public String toInstantiationType(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return instantiationTypes.get("array") + "<" + getSchemaType(inner) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -1000,21 +999,21 @@ public class RustServerCodegen extends AbstractRustCodegen implements CodegenCon
         CodegenModel mdl = super.fromModel(name, model);
 
         if (ModelUtils.isArraySchema(model)) {
-            ArraySchema am = (ArraySchema) model;
+            Schema inner = ModelUtils.getSchemaItems(model);
             String xmlName = null;
 
             // Detect XML list where the inner item is defined directly.
-            if ((am.getItems() != null) &&
+            if ((inner != null) &&
-                    (am.getItems().getXml() != null)) {
+                    (inner.getXml() != null)) {
-                xmlName = am.getItems().getXml().getName();
+                xmlName = inner.getXml().getName();
             }
 
             // Detect XML list where the inner item is a reference.
-            if (am.getXml() != null && am.getXml().getWrapped() &&
+            if (model.getXml() != null && model.getXml().getWrapped() &&
-                    am.getItems() != null &&
+                    inner != null &&
-                    !StringUtils.isEmpty(am.getItems().get$ref())) {
+                    !StringUtils.isEmpty(inner.get$ref())) {
                 Schema inner_schema = allDefinitions.get(
-                        ModelUtils.getSimpleRef(am.getItems().get$ref()));
+                        ModelUtils.getSimpleRef(inner.get$ref()));
 
                 if (inner_schema.getXml() != null &&
                         inner_schema.getXml().getName() != null) {

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaAkkaClientCodegen.java

@@ -295,9 +295,8 @@ public class ScalaAkkaClientCodegen extends AbstractScalaCodegen implements Code
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "Map[String, " + inner + "].empty ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            if (ModelUtils.isSet(p)) {
-            if (ModelUtils.isSet(ap)) {
                 return "Set[" + inner + "].empty ";
             }
             return "Seq[" + inner + "].empty ";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaFinchServerCodegen.java

@@ -261,8 +261,7 @@ public class ScalaFinchServerCodegen extends DefaultCodegen implements CodegenCo
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaGatlingCodegen.java

@@ -384,8 +384,7 @@ public class ScalaGatlingCodegen extends AbstractScalaCodegen implements Codegen
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaHttp4sServerCodegen.java

@@ -711,8 +711,7 @@ public class ScalaHttp4sServerCodegen extends DefaultCodegen implements CodegenC
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaPekkoClientCodegen.java

@@ -295,9 +295,8 @@ public class ScalaPekkoClientCodegen extends AbstractScalaCodegen implements Cod
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "Map[String, " + inner + "].empty ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            if (ModelUtils.isSet(p)) {
-            if (ModelUtils.isSet(ap)) {
                 return "Set[" + inner + "].empty ";
             }
             return "Seq[" + inner + "].empty ";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaPlayFrameworkServerCodegen.java

@@ -369,7 +369,7 @@ public class ScalaPlayFrameworkServerCodegen extends AbstractScalaCodegen implem
         }
 
         if (ModelUtils.isArraySchema(p)) {
-            Schema items = ((ArraySchema) p).getItems();
+            Schema items = ModelUtils.getSchemaItems(p);
             String inner = getSchemaType(items);
             if (ModelUtils.isSet(p)) {
                 return "Set.empty[" + inner + "]";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttp4ClientCodegen.java

@@ -413,9 +413,8 @@ public class ScalaSttp4ClientCodegen extends AbstractScalaCodegen implements Cod
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "Map[String, " + inner + "].empty ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            if (ModelUtils.isSet(p)) {
-            if (ModelUtils.isSet(ap)) {
                 return "Set[" + inner + "].empty ";
             }
             return "Seq[" + inner + "].empty ";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaSttpClientCodegen.java

@@ -431,9 +431,8 @@ public class ScalaSttpClientCodegen extends AbstractScalaCodegen implements Code
             String inner = getSchemaType(ModelUtils.getAdditionalProperties(p));
             return "Map[String, " + inner + "].empty ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            if (ModelUtils.isSet(p)) {
-            if (ModelUtils.isSet(ap)) {
                 return "Set[" + inner + "].empty ";
             }
             return "Seq[" + inner + "].empty ";

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalazClientCodegen.java

@@ -193,9 +193,8 @@ public class ScalazClientCodegen extends AbstractScalaCodegen implements Codegen
 
             return "Map.empty[String, " + inner + "] ";
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
+            String collectionType = ModelUtils.isSet(p) ? typeMapping.get("set") : typeMapping.get("array");
-            String collectionType = ModelUtils.isSet(ap) ? typeMapping.get("set") : typeMapping.get("array");
 
             // We assume that users would map these collections to a monoid with an identity function
             // There's no reason to assume mutable structure here (which may make consumption more difficult)

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/StaticHtml2Generator.java

@@ -133,8 +133,7 @@ public class StaticHtml2Generator extends DefaultCodegen implements CodegenConfi
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/StaticHtmlGenerator.java

@@ -116,8 +116,7 @@ public class StaticHtmlGenerator extends DefaultCodegen implements CodegenConfig
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return getSchemaType(p) + "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/Swift5ClientCodegen.java

@@ -394,8 +394,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
         if (additionalProperties != null) {
             Schema inner = null;
             if (ModelUtils.isArraySchema(schema)) {
-                ArraySchema ap = (ArraySchema) schema;
+                inner = ModelUtils.getSchemaItems(schema);
-                inner = ap.getItems();
             } else if (ModelUtils.isMapSchema(schema)) {
                 inner = ModelUtils.getAdditionalProperties(schema);
             }
@@ -676,8 +675,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return ModelUtils.isSet(p) ? "Set<" + getTypeDeclaration(inner) + ">" : "[" + getTypeDeclaration(inner) + "]";
         } else if (ModelUtils.isMapSchema(p)) {
             Schema inner = ModelUtils.getAdditionalProperties(p);
@@ -794,8 +792,7 @@ public class Swift5ClientCodegen extends DefaultCodegen implements CodegenConfig
         if (ModelUtils.isMapSchema(p)) {
             return getSchemaType(ModelUtils.getAdditionalProperties(p));
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             return ModelUtils.isSet(p) ? "Set<" + inner + ">" : "[" + inner + "]";
         }
         return null;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/SwiftCombineClientCodegen.java

@@ -289,7 +289,7 @@ public class SwiftCombineClientCodegen extends DefaultCodegen implements Codegen
         Schema<?> schema = ModelUtils.unaliasSchema(this.openAPI, p, importMapping);
         Schema<?> target = ModelUtils.isGenerateAliasAsModel() ? p : schema;
         if (ModelUtils.isArraySchema(target)) {
-            Schema<?> items = getSchemaItems((ArraySchema) schema);
+            Schema<?> items = ModelUtils.getSchemaItems(schema);
             return ModelUtils.isSet(target) && ModelUtils.isObjectSchema(items) ? "Set<" + getTypeDeclaration(items) + ">" : "[" + getTypeDeclaration(items) + "]";
         } else if (ModelUtils.isMapSchema(target)) {
             // Note: ModelUtils.isMapSchema(p) returns true when p is a composed schema that also defines
@@ -422,8 +422,7 @@ public class SwiftCombineClientCodegen extends DefaultCodegen implements Codegen
         if (ModelUtils.isMapSchema(p)) {
             return getSchemaType(ModelUtils.getAdditionalProperties(p));
         } else if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            String inner = getSchemaType(ModelUtils.getSchemaItems(p));
-            String inner = getSchemaType(ap.getItems());
             return ModelUtils.isSet(p) ? "Set<" + inner + ">" : "[" + inner + "]";
         }
         return null;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptClientCodegen.java

@@ -482,7 +482,7 @@ public class TypeScriptClientCodegen extends AbstractTypeScriptClientCodegen imp
     public String getTypeDeclaration(Schema p) {
         Schema inner;
         if (ModelUtils.isArraySchema(p)) {
-            inner = ((ArraySchema) p).getItems();
+            inner = ModelUtils.getSchemaItems(p);
             return this.getSchemaType(p) + "<" + this.getTypeDeclaration(unaliasSchema(inner)) + ">";
         } else if (ModelUtils.isMapSchema(p)) {
             inner = getSchemaAdditionalProperties(p);
@@ -787,8 +787,7 @@ public class TypeScriptClientCodegen extends AbstractTypeScriptClientCodegen imp
             }
             return fullPrefix + example + closeChars;
         } else if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema arrayschema = (ArraySchema) schema;
+            Schema itemSchema = ModelUtils.getSchemaItems(schema);
-            Schema itemSchema = arrayschema.getItems();
             String itemModelName = getModelName(itemSchema);
             if (objExample instanceof Iterable && itemModelName == null) {
                 // If the example is already a list, return it directly instead of wrongly wrap it in another list
@@ -919,8 +918,7 @@ public class TypeScriptClientCodegen extends AbstractTypeScriptClientCodegen imp
         } else if (simpleStringSchema(schema)) {
             return propName + "_example";
         } else if (ModelUtils.isArraySchema(schema)) {
-            ArraySchema arraySchema = (ArraySchema) schema;
+            Schema itemSchema = ModelUtils.getSchemaItems(schema);
-            Schema itemSchema = arraySchema.getItems();
             example = getObjectExample(itemSchema);
             if (example != null) {
                 return example;

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/TypeScriptNodeClientCodegen.java

@@ -337,7 +337,7 @@ public class TypeScriptNodeClientCodegen extends AbstractTypeScriptClientCodegen
         Schema additionalProperties = ModelUtils.getAdditionalProperties(schema);
         codegenModel.additionalPropertiesType = getSchemaType(additionalProperties);
         if ("array".equalsIgnoreCase(codegenModel.additionalPropertiesType)) {
-            codegenModel.additionalPropertiesType += '<' + getSchemaType(((ArraySchema) additionalProperties).getItems()) + '>';
+            codegenModel.additionalPropertiesType += '<' + getSchemaType((ModelUtils.getSchemaItems(additionalProperties))) + '>';
         }
         addImport(codegenModel, codegenModel.additionalPropertiesType);
     }

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/XojoClientCodegen.java

@@ -235,8 +235,7 @@ public class XojoClientCodegen extends DefaultCodegen implements CodegenConfig {
     @Override
     public String getTypeDeclaration(Schema p) {
         if (ModelUtils.isArraySchema(p)) {
-            ArraySchema ap = (ArraySchema) p;
+            Schema inner = ModelUtils.getSchemaItems(p);
-            Schema inner = ap.getItems();
             return super.getTypeDeclaration(inner);
         }
         return super.getTypeDeclaration(p);

modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/ModelUtils.java

@@ -20,6 +20,7 @@ package org.openapitools.codegen.utils;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import io.swagger.v3.core.util.AnnotationsUtils;
+import io.swagger.v3.core.util.Json;
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.Operation;
 import io.swagger.v3.oas.models.PathItem;
@@ -356,8 +357,8 @@ public class ModelUtils {
                     visitSchema(openAPI, s, mimeType, visitedSchemas, visitor);
                 }
             }
-        } else if (schema instanceof ArraySchema) {
+        } else if (ModelUtils.isArraySchema(schema)) {
-            Schema itemsSchema = ((ArraySchema) schema).getItems();
+            Schema itemsSchema = ModelUtils.getSchemaItems(schema);
             if (itemsSchema != null) {
                 visitSchema(openAPI, itemsSchema, mimeType, visitedSchemas, visitor);
             }
@@ -594,7 +595,44 @@ public class ModelUtils {
      * @return true if the specified schema is an Array schema.
      */
     public static boolean isArraySchema(Schema schema) {
-        return (schema instanceof ArraySchema);
+        if (schema == null) {
+            return false;
+        }
+
+        if (schema instanceof JsonSchema) { // 3.1 spec
+            if (schema.getTypes() != null && schema.getTypes().contains("array")) {
+                return true;
+            } else {
+                return false;
+            }
+        } else { // 3.0 spec
+            return (schema instanceof ArraySchema) || "array".equals(schema.getType());
+        }
+
+    }
+
+    /**
+     * Return the schema in the array's item. Null if schema is not an array.
+     *
+     * @param schema the OAS schema
+     * @return item schema.
+     */
+    public static Schema<?> getSchemaItems(Schema schema) {
+        if (!isArraySchema(schema)) {
+            return null;
+        }
+
+        Schema<?> items = schema.getItems();
+        if (items == null) {
+            if (schema instanceof JsonSchema) { // 3.1 spec
+                // do nothing as the schema may contain prefixItems only
+            } else { // 3.0 spec, default to string
+                LOGGER.error("Undefined array inner type for `{}`. Default to String.", schema.getName());
+                items = new StringSchema().description("TODO default missing array inner type to string");
+                schema.setItems(items);
+            }
+        }
+        return items;
     }
 
     public static boolean isSet(Schema schema) {
@@ -1272,7 +1310,7 @@ public class ModelUtils {
                 }
             }
         } else if (isArraySchema(schema)) {
-            Schema itemsSchema = ((ArraySchema) schema).getItems();
+            Schema itemsSchema = ModelUtils.getSchemaItems(schema);
             if (itemsSchema != null) {
                 return hasSelfReference(openAPI, itemsSchema, visitedSchemaNames);
             }

modules/openapi-generator/src/test/java/org/openapitools/codegen/OpenAPINormalizerTest.java

@@ -589,4 +589,53 @@ public class OpenAPINormalizerTest {
         assertEquals(((Schema) schema2.getProperties().get("my_enum")).getAnyOf(), null);
         assertEquals(((Schema) schema2.getProperties().get("my_enum")).get$ref(), "#/components/schemas/MyEnum");
     }
+
+    @Test
+    public void testOpenAPINormalizerProcessingArraySchema31Spec() {
+        // to test array schema processing in 3.1 spec
+        OpenAPI openAPI = TestUtils.parseSpec("src/test/resources/3_1/issue_18291.yaml");
+
+        Schema schema = openAPI.getComponents().getSchemas().get("Foo");
+        assertEquals(((Schema) schema.getProperties().get("arrayOfStrings")).getTypes().size(), 1);
+        assertEquals(((Schema) schema.getProperties().get("arrayOfStrings")).getTypes().contains("array"), true);
+        assertEquals(((Schema) schema.getProperties().get("arrayOfStrings")).getType(), null);
+        assertEquals(ModelUtils.isArraySchema((Schema) schema.getProperties().get("arrayOfStrings")), true);
+        assertEquals(((Schema) schema.getProperties().get("arrayOfStrings")).getItems().getType(), null);
+        assertEquals(((Schema) schema.getProperties().get("arrayOfStrings")).getItems().getTypes().contains("string"), true);
+
+        Schema schema3 = openAPI.getComponents().getSchemas().get("Bar");
+        assertEquals(((Schema) schema3.getAllOf().get(0)).get$ref(), "#/components/schemas/Foo");
+
+        Schema schema5 = ModelUtils.getSchema(openAPI, ModelUtils.getSimpleRef(((Schema) schema3.getAllOf().get(0)).get$ref()));
+        assertEquals(((Schema) schema5.getProperties().get("arrayOfStrings")).getTypes().size(), 1);
+        assertEquals(((Schema) schema5.getProperties().get("arrayOfStrings")).getTypes().contains("array"), true);
+        assertEquals(((Schema) schema5.getProperties().get("arrayOfStrings")).getType(), null);
+        assertEquals(ModelUtils.isArraySchema((Schema) schema5.getProperties().get("arrayOfStrings")), true);
+        assertEquals(((Schema) schema5.getProperties().get("arrayOfStrings")).getItems().getType(), null);
+        assertEquals(((Schema) schema5.getProperties().get("arrayOfStrings")).getItems().getTypes().contains("string"), true);
+
+        Map<String, String> inputRules = Map.of("NORMALIZE_31SPEC", "true");
+        OpenAPINormalizer openAPINormalizer = new OpenAPINormalizer(openAPI, inputRules);
+        openAPINormalizer.normalize();
+
+        Schema schema2 = openAPI.getComponents().getSchemas().get("Foo");
+        assertEquals(((Schema) schema2.getProperties().get("arrayOfStrings")).getTypes().size(), 1);
+        assertEquals(((Schema) schema2.getProperties().get("arrayOfStrings")).getTypes().contains("array"), true);
+        assertEquals(ModelUtils.isArraySchema((Schema) schema2.getProperties().get("arrayOfStrings")), true);
+        assertEquals(((Schema) schema2.getProperties().get("arrayOfStrings")).getItems().getTypes().contains("string"), true);
+        assertEquals(((Schema) schema2.getProperties().get("arrayOfStrings")).getItems().getType(), "string");
+        assertEquals(((Schema) schema2.getProperties().get("arrayOfStrings")).getType(), "array");
+
+        Schema schema4 = openAPI.getComponents().getSchemas().get("Bar");
+        assertEquals(((Schema) schema4.getAllOf().get(0)).get$ref(), "#/components/schemas/Foo");
+
+        Schema schema6 = ModelUtils.getSchema(openAPI, ModelUtils.getSimpleRef(((Schema) schema4.getAllOf().get(0)).get$ref()));
+        assertEquals(((Schema) schema6.getProperties().get("arrayOfStrings")).getTypes().size(), 1);
+        assertEquals(((Schema) schema6.getProperties().get("arrayOfStrings")).getTypes().contains("array"), true);
+        assertEquals(ModelUtils.isArraySchema((Schema) schema6.getProperties().get("arrayOfStrings")), true);
+        assertEquals(((Schema) schema6.getProperties().get("arrayOfStrings")).getItems().getTypes().contains("string"), true);
+        assertEquals(((Schema) schema6.getProperties().get("arrayOfStrings")).getItems().getType(), "string");
+        assertEquals(((Schema) schema6.getProperties().get("arrayOfStrings")).getType(), "array");
+
+    }
 }

modules/openapi-generator/src/test/resources/3_1/issue_18291.yaml

@@ -0,0 +1,36 @@
+openapi: 3.1.0
+info:
+  title: ""
+  version: ""
+
+paths:
+  /user/getInfo:
+    get:
+      operationId: getUserInfo
+      responses:
+        "200":
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Bar'
+          description: |
+            OK
+      security:
+        - Session: []
+      x-accepts: application/json
+
+components:
+  schemas:
+    Foo:
+      type: object
+      required:
+        - arrayOfStrings
+      properties:
+        arrayOfStrings:
+          type: array
+          items:
+            type: string
+
+    Bar:
+      allOf:
+        - $ref: '#/components/schemas/Foo'

modules/openapi-generator/src/test/resources/3_1/java/petstore.yaml

@@ -909,14 +909,15 @@ components:
       properties: {}
       type: object
       title: HTTPValidationError
-    AnyOfArray:
+    # okhttp-gson doesnot support array of string
-      anyOf:
+    #AnyOfArray:
-        - type: array
+    #  anyOf:
-          items:
+    #    - type: array
-            type: string
+    #      items:
-        - type: array
+    #        type: string
-          items:
+    #    - type: array
-            type: integer
+    #      items:
+    #        type: integer
     ArrayPrefixItems:
       type: array
       description: |

samples/client/petstore/java/okhttp-gson-3.1/.openapi-generator/FILES

@@ -6,7 +6,6 @@ api/openapi.yaml
 build.gradle
 build.sbt
 docs/Animal.md
-docs/AnyOfArray.md
 docs/AnyTypeTest.md
 docs/ArrayOfSameRef.md
 docs/Cat.md
@@ -63,7 +62,6 @@ src/main/java/org/openapitools/client/auth/OAuthOkHttpClient.java
 src/main/java/org/openapitools/client/auth/RetryingOAuth.java
 src/main/java/org/openapitools/client/model/AbstractOpenApiSchema.java
 src/main/java/org/openapitools/client/model/Animal.java
-src/main/java/org/openapitools/client/model/AnyOfArray.java
 src/main/java/org/openapitools/client/model/AnyTypeTest.java
 src/main/java/org/openapitools/client/model/ArrayOfSameRef.java
 src/main/java/org/openapitools/client/model/Cat.java

samples/client/petstore/java/okhttp-gson-3.1/README.md

@@ -145,7 +145,6 @@ Class | Method | HTTP request | Description
 ## Documentation for Models
 
  - [Animal](docs/Animal.md)
- - [AnyOfArray](docs/AnyOfArray.md)
  - [AnyTypeTest](docs/AnyTypeTest.md)
  - [ArrayOfSameRef](docs/ArrayOfSameRef.md)
  - [Cat](docs/Cat.md)

samples/client/petstore/java/okhttp-gson-3.1/api/openapi.yaml

@@ -1022,12 +1022,6 @@ components:
       properties: {}
       title: HTTPValidationError
       type: object
-    AnyOfArray:
-      anyOf:
-      - items:
-          type: string
-      - items:
-          type: integer
     ArrayPrefixItems:
       description: |
         An item that was added to the queue.

samples/client/petstore/java/okhttp-gson-3.1/docs/AnyOfArray.md

@@ -1,12 +0,0 @@
-
-
-# AnyOfArray
-
-
-## Properties
-
-| Name | Type | Description | Notes |
-|------------ | ------------- | ------------- | -------------|
-
-
-

samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/JSON.java

@@ -129,7 +129,6 @@ public class JSON {
         gsonBuilder.registerTypeAdapter(OffsetDateTime.class, offsetDateTimeTypeAdapter);
         gsonBuilder.registerTypeAdapter(LocalDate.class, localDateTypeAdapter);
         gsonBuilder.registerTypeAdapter(byte[].class, byteArrayAdapter);
-        gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.AnyOfArray.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.AnyTypeTest.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.ArrayOfSameRef.CustomTypeAdapterFactory());
         gsonBuilder.registerTypeAdapterFactory(new org.openapitools.client.model.Cat.CustomTypeAdapterFactory());

samples/client/petstore/java/okhttp-gson-3.1/src/main/java/org/openapitools/client/model/AnyOfArray.java

@@ -1,217 +0,0 @@
-/*
- * OpenAPI Petstore
- * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
- *
- * The version of the OpenAPI document: 1.0.0
- * 
- *
- * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
- * https://openapi-generator.tech
- * Do not edit the class manually.
- */
-
-
-package org.openapitools.client.model;
-
-import java.util.Objects;
-
-
-
-import java.io.IOException;
-import java.lang.reflect.Type;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-
-import com.google.gson.Gson;
-import com.google.gson.GsonBuilder;
-import com.google.gson.JsonParseException;
-import com.google.gson.TypeAdapter;
-import com.google.gson.TypeAdapterFactory;
-import com.google.gson.reflect.TypeToken;
-import com.google.gson.JsonPrimitive;
-import com.google.gson.annotations.JsonAdapter;
-import com.google.gson.annotations.SerializedName;
-import com.google.gson.stream.JsonReader;
-import com.google.gson.stream.JsonWriter;
-import com.google.gson.JsonDeserializationContext;
-import com.google.gson.JsonDeserializer;
-import com.google.gson.JsonSerializationContext;
-import com.google.gson.JsonSerializer;
-import com.google.gson.JsonElement;
-import com.google.gson.JsonObject;
-import com.google.gson.JsonArray;
-import com.google.gson.JsonParseException;
-
-import org.openapitools.client.JSON;
-
-@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", comments = "Generator version: 7.5.0-SNAPSHOT")
-public class AnyOfArray extends AbstractOpenApiSchema {
-    private static final Logger log = Logger.getLogger(AnyOfArray.class.getName());
-
-    public static class CustomTypeAdapterFactory implements TypeAdapterFactory {
-        @SuppressWarnings("unchecked")
-        @Override
-        public <T> TypeAdapter<T> create(Gson gson, TypeToken<T> type) {
-            if (!AnyOfArray.class.isAssignableFrom(type.getRawType())) {
-                return null; // this class only serializes 'AnyOfArray' and its subtypes
-            }
-            final TypeAdapter<JsonElement> elementAdapter = gson.getAdapter(JsonElement.class);
-            final TypeAdapter<Object> adapterObject = gson.getDelegateAdapter(this, TypeToken.get(Object.class));
-
-            return (TypeAdapter<T>) new TypeAdapter<AnyOfArray>() {
-                @Override
-                public void write(JsonWriter out, AnyOfArray value) throws IOException {
-                    if (value == null || value.getActualInstance() == null) {
-                        elementAdapter.write(out, null);
-                        return;
-                    }
-
-                    // check if the actual instance is of the type `Object`
-                    if (value.getActualInstance() instanceof Object) {
-                      JsonPrimitive primitive = adapterObject.toJsonTree((Object)value.getActualInstance()).getAsJsonPrimitive();
-                      elementAdapter.write(out, primitive);
-                      return;
-                    }
-                    throw new IOException("Failed to serialize as the type doesn't match anyOf schemae: Object");
-                }
-
-                @Override
-                public AnyOfArray read(JsonReader in) throws IOException {
-                    Object deserialized = null;
-                    JsonElement jsonElement = elementAdapter.read(in);
-
-                    ArrayList<String> errorMessages = new ArrayList<>();
-                    TypeAdapter actualAdapter = elementAdapter;
-
-                    // deserialize Object
-                    try {
-                      // validate the JSON object to see if any exception is thrown
-                      if(!jsonElement.getAsJsonPrimitive().isNumber()) {
-                        throw new IllegalArgumentException(String.format("Expected json element to be of type Number in the JSON string but got `%s`", jsonElement.toString()));
-                      }
-                      actualAdapter = adapterObject;
-                      AnyOfArray ret = new AnyOfArray();
-                      ret.setActualInstance(actualAdapter.fromJsonTree(jsonElement));
-                      return ret;
-                    } catch (Exception e) {
-                      // deserialization failed, continue
-                      errorMessages.add(String.format("Deserialization for Object failed with `%s`.", e.getMessage()));
-                      log.log(Level.FINER, "Input data does not match schema 'Object'", e);
-                    }
-
-                    throw new IOException(String.format("Failed deserialization for AnyOfArray: no class matches result, expected at least 1. Detailed failure message for anyOf schemas: %s. JSON: %s", errorMessages, jsonElement.toString()));
-                }
-            }.nullSafe();
-        }
-    }
-
-    // store a list of schema names defined in anyOf
-    public static final Map<String, Class<?>> schemas = new HashMap<String, Class<?>>();
-
-    public AnyOfArray() {
-        super("anyOf", Boolean.FALSE);
-    }
-
-    public AnyOfArray(Object o) {
-        super("anyOf", Boolean.FALSE);
-        setActualInstance(o);
-    }
-
-    static {
-        schemas.put("Object", Object.class);
-    }
-
-    @Override
-    public Map<String, Class<?>> getSchemas() {
-        return AnyOfArray.schemas;
-    }
-
-    /**
-     * Set the instance that matches the anyOf child schema, check
-     * the instance parameter is valid against the anyOf child schemas:
-     * Object
-     *
-     * It could be an instance of the 'anyOf' schemas.
-     */
-    @Override
-    public void setActualInstance(Object instance) {
-        if (instance instanceof Object) {
-            super.setActualInstance(instance);
-            return;
-        }
-
-        throw new RuntimeException("Invalid instance type. Must be Object");
-    }
-
-    /**
-     * Get the actual instance, which can be the following:
-     * Object
-     *
-     * @return The actual instance (Object)
-     */
-    @Override
-    public Object getActualInstance() {
-        return super.getActualInstance();
-    }
-
-    /**
-     * Get the actual instance of `Object`. If the actual instance is not `Object`,
-     * the ClassCastException will be thrown.
-     *
-     * @return The actual instance of `Object`
-     * @throws ClassCastException if the instance is not `Object`
-     */
-    public Object getObject() throws ClassCastException {
-        return (Object)super.getActualInstance();
-    }
-
- /**
-  * Validates the JSON Element and throws an exception if issues found
-  *
-  * @param jsonElement JSON Element
-  * @throws IOException if the JSON Element is invalid with respect to AnyOfArray
-  */
-  public static void validateJsonElement(JsonElement jsonElement) throws IOException {
-    // validate anyOf schemas one by one
-    ArrayList<String> errorMessages = new ArrayList<>();
-    // validate the json string with Object
-    try {
-      if(!jsonElement.getAsJsonPrimitive().isNumber()) {
-        throw new IllegalArgumentException(String.format("Expected json element to be of type Number in the JSON string but got `%s`", jsonElement.toString()));
-      }
-      return;
-    } catch (Exception e) {
-      errorMessages.add(String.format("Deserialization for Object failed with `%s`.", e.getMessage()));
-      // continue to the next one
-    }
-    throw new IOException(String.format("The JSON string is invalid for AnyOfArray with anyOf schemas: Object. no class match the result, expected at least 1. Detailed failure message for anyOf schemas: %s. JSON: %s", errorMessages, jsonElement.toString()));
-    
-  }
-
- /**
-  * Create an instance of AnyOfArray given an JSON string
-  *
-  * @param jsonString JSON string
-  * @return An instance of AnyOfArray
-  * @throws IOException if the JSON string is invalid with respect to AnyOfArray
-  */
-  public static AnyOfArray fromJson(String jsonString) throws IOException {
-    return JSON.getGson().fromJson(jsonString, AnyOfArray.class);
-  }
-
- /**
-  * Convert an instance of AnyOfArray to an JSON string
-  *
-  * @return JSON string
-  */
-  public String toJson() {
-    return JSON.getGson().toJson(this);
-  }
-}
-

samples/client/petstore/java/okhttp-gson-3.1/src/test/java/org/openapitools/client/model/AnyOfArrayTest.java

@@ -1,33 +0,0 @@
-/*
- * OpenAPI Petstore
- * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
- *
- * The version of the OpenAPI document: 1.0.0
- * 
- *
- * NOTE: This class is auto generated by OpenAPI Generator (https://openapi-generator.tech).
- * https://openapi-generator.tech
- * Do not edit the class manually.
- */
-
-
-package org.openapitools.client.model;
-
-import org.junit.jupiter.api.Disabled;
-import org.junit.jupiter.api.Test;
-
-/**
- * Model tests for AnyOfArray
- */
-public class AnyOfArrayTest {
-    private final AnyOfArray model = new AnyOfArray();
-
-    /**
-     * Model tests for AnyOfArray
-     */
-    @Test
-    public void testAnyOfArray() {
-        // TODO: test AnyOfArray
-    }
-
-}