Add x-implements for java enums (#20778)

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

@@ -1113,7 +1113,7 @@ public class JavaClientCodegen extends AbstractJavaCodegen
                     cm.anyOf.remove("ModelNull");
                 }
             }
-            if (this.parcelableModel) {
+            if (this.parcelableModel && !cm.isEnum) {
                 ((ArrayList<String>) cm.getVendorExtensions().get("x-implements")).add("Parcelable");
             }
         }

modules/openapi-generator/src/main/resources/Java/libraries/microprofile/enumClass.mustache

@@ -8,7 +8,7 @@
   @JsonbTypeDeserializer({{datatypeWithEnum}}.Deserializer.class)
   {{/jsonb}}
 {{/withXml}}
-  {{>additionalEnumTypeAnnotations}}public enum {{datatypeWithEnum}} {
+  {{>additionalEnumTypeAnnotations}}public enum {{datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
 
     {{#allowableValues}}
     {{#withXml}}

modules/openapi-generator/src/main/resources/Java/libraries/microprofile/enumOuterClass.mustache

@@ -13,7 +13,7 @@ import java.net.URI;
 @JsonbTypeSerializer({{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}.Serializer.class)
 @JsonbTypeDeserializer({{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}.Deserializer.class)
 {{/jsonb}}
-{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}} {
+{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
   {{#gson}}
   {{#allowableValues}}{{#enumVars}}
   @SerializedName({{#isInteger}}"{{/isInteger}}{{#isDouble}}"{{/isDouble}}{{#isLong}}"{{/isLong}}{{#isFloat}}"{{/isFloat}}{{{value}}}{{#isInteger}}"{{/isInteger}}{{#isDouble}}"{{/isDouble}}{{#isLong}}"{{/isLong}}{{#isFloat}}"{{/isFloat}})

modules/openapi-generator/src/main/resources/Java/libraries/native/modelEnum.mustache

@@ -23,7 +23,7 @@ import java.net.URI;
 @JsonbTypeSerializer({{datatypeWithEnum}}.Serializer.class)
 @JsonbTypeDeserializer({{datatypeWithEnum}}.Deserializer.class)
 {{/jsonb}}
-{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}} {
+{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
   {{#allowableValues}}{{#enumVars}}
     {{#enumDescription}}
   /**

modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/modelEnum.mustache

@@ -12,7 +12,7 @@ import com.google.gson.stream.JsonWriter;
  * {{description}}{{^description}}Gets or Sets {{{name}}}{{/description}}
  */
 @JsonAdapter({{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}.Adapter.class)
-{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}} {
+{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
   {{#allowableValues}}{{#enumVars}}
     {{#enumDescription}}
   /**

modules/openapi-generator/src/main/resources/Java/libraries/okhttp-gson/modelInnerEnum.mustache

@@ -6,7 +6,7 @@
   @XmlType(name="{{datatypeWithEnum}}")
   @XmlEnum({{dataType}}.class)
 {{/withXml}}
-  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}} {
+  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
     {{#allowableValues}}
       {{#enumVars}}
     {{#enumDescription}}

modules/openapi-generator/src/main/resources/Java/modelEnum.mustache

@@ -23,7 +23,7 @@ import java.net.URI;
 @JsonbTypeSerializer({{datatypeWithEnum}}.Serializer.class)
 @JsonbTypeDeserializer({{datatypeWithEnum}}.Deserializer.class)
 {{/jsonb}}
-{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}} {
+{{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
   {{#allowableValues}}{{#enumVars}}
     {{#enumDescription}}
   /**

modules/openapi-generator/src/main/resources/Java/modelInnerEnum.mustache

@@ -12,7 +12,7 @@
   @XmlType(name="{{datatypeWithEnum}}")
   @XmlEnum({{dataType}}.class)
 {{/withXml}}
-  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}} {
+  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
     {{#allowableValues}}
       {{#enumVars}}
     {{#enumDescription}}

modules/openapi-generator/src/main/resources/JavaSpring/enumClass.mustache

@@ -1,7 +1,7 @@
   /**
    * {{^description}}Gets or Sets {{{name}}}{{/description}}{{{description}}}
    */
-  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}} {
+  {{>additionalEnumTypeAnnotations}}public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{classname}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
     {{#gson}}
         {{#allowableValues}}
             {{#enumVars}}

modules/openapi-generator/src/main/resources/JavaSpring/enumOuterClass.mustache

@@ -8,7 +8,7 @@ import com.fasterxml.jackson.annotation.JsonValue;
  */
 {{>additionalEnumTypeAnnotations}}
 {{>generatedAnnotation}}
-public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}} {
+public enum {{{datatypeWithEnum}}}{{^datatypeWithEnum}}{{{classname}}}{{/datatypeWithEnum}}{{#vendorExtensions.x-implements}}{{#-first}} implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
   {{#gson}}
   {{#allowableValues}}{{#enumVars}}
   {{#enumDescription}}

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

@@ -3463,4 +3463,17 @@ public class JavaClientCodegenTest {
                 "responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<LocationData>() {})"
         );
     }
+
+    @Test
+    public void testEnumWithImplements() {
+        final Path output = newTempFolder();
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/enum-implements.yaml");
+        JavaClientCodegen codegen = new JavaClientCodegen();
+        codegen.setOutputDir(output.toString());
+
+        Map<String, File> files = new DefaultGenerator().opts(new ClientOptInput().openAPI(openAPI).config(codegen))
+                .generate().stream().collect(Collectors.toMap(File::getName, Function.identity()));
+
+        JavaFileAssert.assertThat(files.get("Type.java")).fileContains("Type implements org.openapitools.java.EnumInterface {");
+    }
 }

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

@@ -5370,4 +5370,17 @@ public class SpringCodegenTest {
                         "this.name = Optional.of(name);"
                 );
     }
+
+    @Test
+    public void testEnumWithImplements() {
+        final Path output = newTempFolder();
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/3_0/enum-implements.yaml");
+        SpringCodegen codegen = new SpringCodegen();
+        codegen.setOutputDir(output.toString());
+
+        Map<String, File> files = new DefaultGenerator().opts(new ClientOptInput().openAPI(openAPI).config(codegen))
+                .generate().stream().collect(Collectors.toMap(File::getName, Function.identity()));
+
+        JavaFileAssert.assertThat(files.get("Type.java")).fileContains("Type implements org.openapitools.java.EnumInterface {");
+    }
 }

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

@@ -0,0 +1,33 @@
+openapi: 3.0.0
+info:
+  title: Sample API
+  description: API description in Markdown.
+  version: 1.0.0
+paths:
+  /ponies:
+    get:
+      summary: Returns all animals.
+      description: Optional extended description in Markdown.
+      responses:
+        200:
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: array
+                items:
+                  $ref: '#/components/schemas/Pony'
+components:
+  schemas:
+    Pony:
+      type: object
+      properties:
+        type:
+          $ref: '#/components/schemas/Type'
+    Type:
+      type: string
+      x-implements: org.openapitools.java.EnumInterface
+      enum:
+        - Earth
+        - Pegasi
+        - Unicorn