Fix AbstractJavaCodegen ability to customize container types

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

@@ -1598,16 +1598,16 @@ public void postProcessModelProperty(CodegenModel model, CodegenProperty propert
         }
 
         if ("array".equals(property.containerType)) {
-            model.imports.add("ArrayList");
+            model.imports.add(instantiationTypes.get("array"));
             model.imports.add("Arrays");
         } else if ("set".equals(property.containerType)) {
-            model.imports.add("LinkedHashSet");
+            model.imports.add(instantiationTypes.get("set"));
             if (!openApiNullable || !property.isNullable) { // cannot be wrapped to nullable
                 model.imports.add("JsonDeserialize");
-                property.vendorExtensions.put("x-setter-extra-annotation", "@JsonDeserialize(as = LinkedHashSet.class)");
+                property.vendorExtensions.put("x-setter-extra-annotation", "@JsonDeserialize(as = " + instantiationTypes.get("set") + ".class)");
             }
         } else if ("map".equals(property.containerType)) {
-            model.imports.add("HashMap");
+            model.imports.add(instantiationTypes.get("map"));
         }
 
         if (!BooleanUtils.toBoolean(model.isEnum)) {

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

@@ -844,6 +844,40 @@ public void maplikeDefaultValueForModelWithStringToModelMapping() {
         Assert.assertEquals(defaultValue, "null", "Expected string-ref map aliased model to default to null since nullable is not set to tru");
     }
 
+    @Test
+    public void uniqueItemsSet() {
+        final P_AbstractJavaCodegen codegen = new P_AbstractJavaCodegen();
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/setSchema.yaml");
+        codegen.additionalProperties().put(CodegenConstants.GENERATE_ALIAS_AS_MODEL, true);
+        codegen.setOpenAPI(openAPI);
+
+        Schema schema = openAPI.getComponents().getSchemas().get("Response");
+        CodegenModel cm = codegen.fromModel("Response", schema);
+        Assert.assertFalse(cm.getImports().contains("List"), "expect List import");
+        Assert.assertFalse(cm.getImports().contains("ArrayList"), "expect ArrayList import");
+        Assert.assertTrue(cm.getImports().contains("Set"), "expect no Set import");
+        Assert.assertTrue(cm.getImports().contains("LinkedHashSet"), "expect no LinkedHashSet import");
+    }
+
+    @Test
+    public void uniqueItemsArray() {
+        final P_AbstractJavaCodegen codegen = new P_AbstractJavaCodegen();
+        // overrides to keep uniqueItems=true arrays as arrays in generated code
+        codegen.typeMapping().put("set", codegen.typeMapping().get("array"));
+        codegen.instantiationTypes().put("set", codegen.instantiationTypes().get("array"));
+
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/setSchema.yaml");
+        codegen.additionalProperties().put(CodegenConstants.GENERATE_ALIAS_AS_MODEL, true);
+        codegen.setOpenAPI(openAPI);
+
+        Schema schema = openAPI.getComponents().getSchemas().get("Response");
+        CodegenModel cm = codegen.fromModel("Response", schema);
+        Assert.assertTrue(cm.getImports().contains("List"), "expect List import");
+        Assert.assertTrue(cm.getImports().contains("ArrayList"), "expect ArrayList import");
+        Assert.assertFalse(cm.getImports().contains("Set"), "expect no Set import");
+        Assert.assertFalse(cm.getImports().contains("LinkedHashSet"), "expect no LinkedHashSet import");
+    }
+
     @Test
     public void srcMainFolderShouldNotBeOperatingSystemSpecificPaths() {
         // it's not responsibility of the generator to fix OS-specific paths. This is left to template manager.

modules/openapi-generator/src/test/resources/3_0/setSchema.yaml

@@ -0,0 +1,26 @@
+openapi: 3.0.0
+paths:
+  /examples:
+    get:
+      tags:
+        - Examples
+      summary: Get a list of transactions
+      operationId: getFilteredTransactions
+      responses:
+        200:
+          description: A list of deleted consumers
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/Response'
+
+components:
+  schemas:
+    Response:
+      type: object
+      properties:
+        something:
+          type: array
+          uniqueItems: true
+          items:
+            type: string