fix object and complex compposed schema check (#18352)

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

@@ -460,7 +460,7 @@ public class ModelUtils {
 
         return (schema instanceof ObjectSchema) ||
                 // must not be a map
-                (SchemaTypeUtil.OBJECT_TYPE.equals(schema.getType()) && !(schema instanceof MapSchema)) ||
+                (SchemaTypeUtil.OBJECT_TYPE.equals(schema.getType()) && !(ModelUtils.isMapSchema(schema))) ||
                 // must have at least one property
                 (schema.getType() == null && schema.getProperties() != null && !schema.getProperties().isEmpty());
     }
@@ -509,10 +509,6 @@ public class ModelUtils {
      * @return true if the specified schema is a Composed schema.
      */
     public static boolean isComplexComposedSchema(Schema schema) {
-        if (!(schema instanceof ComposedSchema)) {
-            return false;
-        }
-
         int count = 0;
 
         if (schema.getAllOf() != null && !schema.getAllOf().isEmpty()) {

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

@@ -384,5 +384,11 @@ public class ModelUtilsTest {
         Assert.assertFalse(anyof2.getAnyOf().isEmpty());
         Assert.assertTrue(ModelUtils.hasAnyOf(anyof2));
         Assert.assertTrue(ModelUtils.isAnyOf(anyof2));
+
+        Schema objectSchema = ModelUtils.getSchema(openAPI, "ObjectSchema");
+        Assert.assertTrue(ModelUtils.isMapSchema(objectSchema));
+
+        Schema complexComposedSchema = ModelUtils.getSchema(openAPI, "ComplexComposedSchema");
+        Assert.assertTrue(ModelUtils.isComplexComposedSchema(complexComposedSchema));
     }
 }

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

@@ -64,4 +64,19 @@ components:
         oneof1:
           oneOf:
             - type: string
-            - type: integer
+            - type: integer
+    ObjectSchema:
+      type: object
+      additionalProperties: false
+      properties:
+        name:
+          type: string
+        address:
+          type: string
+    ComplexComposedSchema:
+      oneOf:
+        - type: string
+        - type: integer
+      anyOf:
+        - type: string
+        - type: number