[Java] [SpringClient] Introduce setting for sealed oneOf interfaces for Spring clients (OpenAPITools#21586)

* Add setting for generating the oneOf interfaces as sealed interfaces

* Generate samples

* Add internal java17 additionalProperty setting

* Move samples to highlight that they do not use the petstore

* Align documentation

* Update samples

* Align documentation

* Update mustache files and samples to change gradle settings to java17

Author: Mattias-Sehlstedt

.github/workflows/samples-java-client-jdk17.yaml

@@ -6,13 +6,15 @@ on:
       - samples/client/petstore/java/resttemplate-jakarta/**
       - samples/client/petstore/java/webclient-jakarta/**
       - samples/client/petstore/java/restclient-*/**
+      - samples/client/others/java/webclient-sealedInterface/**
       - samples/client/petstore/java/webclient-useSingleRequestParameter/**
       - samples/client/others/java/restclient-enum-in-multipart/**
   pull_request:
     paths:
       - samples/client/petstore/java/resttemplate-jakarta/**
       - samples/client/petstore/java/webclient-jakarta/**
       - samples/client/petstore/java/restclient-*/**
+      - samples/client/others/java/webclient-sealedInterface/**
       - samples/client/petstore/java/webclient-useSingleRequestParameter/**
       - samples/client/others/java/restclient-enum-in-multipart/**
 jobs:
@@ -31,6 +33,7 @@ jobs:
           - samples/client/petstore/java/restclient-swagger2
           - samples/client/petstore/java/restclient-useSingleRequestParameter
           - samples/client/petstore/java/restclient-useSingleRequestParameter-static
+          - samples/client/others/java/webclient-sealedInterface
           - samples/client/petstore/java/webclient-useSingleRequestParameter
           - samples/client/others/java/restclient-enum-in-multipart
     steps:

bin/configs/java-webclient-sealedInterface.yaml

@@ -0,0 +1,10 @@
+generatorName: java
+outputDir: samples/client/others/java/webclient-sealedInterface
+library: webclient
+inputSpec: modules/openapi-generator/src/test/resources/3_0/oneof_polymorphism_and_inheritance.yaml
+templateDir: modules/openapi-generator/src/main/resources/Java
+additionalProperties:
+  artifactId: sealed-interface-webclient
+  hideGenerationTimestamp: "true"
+  useOneOfInterfaces: true
+  useSealedOneOfInterfaces: true

docs/generators/java-microprofile.md

@@ -103,6 +103,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |useRuntimeException|Use RuntimeException instead of Exception. Only jersey2, jersey3, okhttp-gson, vertx, microprofile support this option.| |false|
 |useRxJava2|Whether to use the RxJava2 adapter with the retrofit2 library. IMPORTANT: This option has been deprecated.| |false|
 |useRxJava3|Whether to use the RxJava3 adapter with the retrofit2 library. IMPORTANT: This option has been deprecated.| |false|
+|useSealedOneOfInterfaces|Generate the oneOf interfaces as sealed interfaces. Only supported for WebClient and RestClient.| |false|
 |useSingleRequestParameter|Setting this property to "true" will generate functions with a single argument containing all API endpoint parameters instead of one argument per parameter. ONLY native, jersey2, jersey3, okhttp-gson, microprofile, Spring RestClient, Spring WebClient support this option. Setting this property to "static" does the same as "true", but also makes the generated arguments class static with single parameter instantiation.| |false|
 |webclientBlockingOperations|Making all WebClient operations blocking(sync). Note that if on operation 'x-webclient-blocking: false' then such operation won't be sync| |false|
 |withAWSV4Signature|whether to include AWS v4 signature support (only available for okhttp-gson library)| |false|

docs/generators/java.md

@@ -103,6 +103,7 @@ These options may be applied as additional-properties (cli) or configOptions (pl
 |useRuntimeException|Use RuntimeException instead of Exception. Only jersey2, jersey3, okhttp-gson, vertx, microprofile support this option.| |false|
 |useRxJava2|Whether to use the RxJava2 adapter with the retrofit2 library. IMPORTANT: This option has been deprecated.| |false|
 |useRxJava3|Whether to use the RxJava3 adapter with the retrofit2 library. IMPORTANT: This option has been deprecated.| |false|
+|useSealedOneOfInterfaces|Generate the oneOf interfaces as sealed interfaces. Only supported for WebClient and RestClient.| |false|
 |useSingleRequestParameter|Setting this property to "true" will generate functions with a single argument containing all API endpoint parameters instead of one argument per parameter. ONLY native, jersey2, jersey3, okhttp-gson, microprofile, Spring RestClient, Spring WebClient support this option. Setting this property to "static" does the same as "true", but also makes the generated arguments class static with single parameter instantiation.| |false|
 |webclientBlockingOperations|Making all WebClient operations blocking(sync). Note that if on operation 'x-webclient-blocking: false' then such operation won't be sync| |false|
 |withAWSV4Signature|whether to include AWS v4 signature support (only available for okhttp-gson library)| |false|

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

@@ -104,6 +104,12 @@ public class JavaClientCodegen extends AbstractJavaCodegen
     public static final String USE_ENUM_CASE_INSENSITIVE = "useEnumCaseInsensitive";
     public static final String FAIL_ON_UNKNOWN_PROPERTIES = "failOnUnknownProperties";
     public static final String SUPPORT_VERTX_FUTURE = "supportVertxFuture";
+    public static final String USE_SEALED_ONE_OF_INTERFACES = "useSealedOneOfInterfaces";
+
+    // Internal configurations
+    public static final String SINGLE_REQUEST_PARAMETER = "singleRequestParameter";
+    public static final String STATIC_REQUEST = "staticRequest";
+    public static final String JAVA_17 = "java17";
 
     public static final String SERIALIZATION_LIBRARY_GSON = "gson";
     public static final String SERIALIZATION_LIBRARY_JACKSON = "jackson";
@@ -142,6 +148,7 @@ public class JavaClientCodegen extends AbstractJavaCodegen
     @Setter protected String errorObjectType;
     @Getter @Setter protected boolean failOnUnknownProperties = false;
     @Setter protected boolean supportVertxFuture = false;
+    @Setter protected boolean useSealedOneOfInterfaces = false;
     protected String authFolder;
     /**
      * Serialization library.
@@ -252,6 +259,7 @@ public JavaClientCodegen() {
         cliOptions.add(CliOption.newBoolean(USE_ENUM_CASE_INSENSITIVE, "Use `equalsIgnoreCase` when String for enum comparison", useEnumCaseInsensitive));
         cliOptions.add(CliOption.newBoolean(FAIL_ON_UNKNOWN_PROPERTIES, "Fail Jackson de-serialization on unknown properties", this.failOnUnknownProperties));
         cliOptions.add(CliOption.newBoolean(SUPPORT_VERTX_FUTURE, "Also generate api methods that return a vertx Future instead of taking a callback. Only `vertx` supports this option. Requires vertx 4 or greater.", this.supportVertxFuture));
+        cliOptions.add(CliOption.newBoolean(USE_SEALED_ONE_OF_INTERFACES, "Generate the oneOf interfaces as sealed interfaces. Only supported for WebClient and RestClient.", this.useSealedOneOfInterfaces));
 
         supportedLibraries.put(JERSEY2, "HTTP client: Jersey client 2.25.1. JSON processing: Jackson 2.17.1");
         supportedLibraries.put(JERSEY3, "HTTP client: Jersey client 3.1.1. JSON processing: Jackson 2.17.1");
@@ -367,8 +375,13 @@ public void processOpts() {
             convertPropertyToBooleanAndWriteBack(USE_RX_JAVA2, this::setUseRxJava2);
         }
         convertPropertyToStringAndWriteBack(CodegenConstants.USE_SINGLE_REQUEST_PARAMETER, this::setUseSingleRequestParameter);
-        writePropertyBack("singleRequestParameter", getSingleRequestParameter());
-        writePropertyBack("staticRequest", getStaticRequest());
+        convertPropertyToBooleanAndWriteBack(USE_SEALED_ONE_OF_INTERFACES, this::setUseSealedOneOfInterfaces);
+        writePropertyBack(SINGLE_REQUEST_PARAMETER, getSingleRequestParameter());
+        writePropertyBack(STATIC_REQUEST, getStaticRequest());
+
+        if (libWebClient && (useSealedOneOfInterfaces || useJakartaEe)) {
+            writePropertyBack(JAVA_17, true);
+        }
 
         if (!useRxJava && !useRxJava2 && !useRxJava3) {
             additionalProperties.put(DO_NOT_USE_RX, true);

modules/openapi-generator/src/main/resources/Java/libraries/restclient/pojo.mustache

@@ -29,7 +29,7 @@
 {{#vendorExtensions.x-class-extra-annotation}}
 {{{vendorExtensions.x-class-extra-annotation}}}
 {{/vendorExtensions.x-class-extra-annotation}}
-public class {{classname}} {{#parent}}extends {{{.}}} {{/parent}}{{#vendorExtensions.x-implements}}{{#-first}}implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{#-last}} {{/-last}}{{/vendorExtensions.x-implements}}{
+public {{>sealed}}class {{classname}} {{#parent}}extends {{{.}}} {{/parent}}{{#vendorExtensions.x-implements}}{{#-first}}implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{#-last}} {{/-last}}{{/vendorExtensions.x-implements}}{{>permits}}{
 {{#serializableModel}}
   private static final long serialVersionUID = 1L;
 

modules/openapi-generator/src/main/resources/Java/libraries/webclient/build.gradle.mustache

@@ -32,14 +32,14 @@ if(hasProperty('target') && target == 'android') {
         }
 
         compileOptions {
-            {{#useJakartaEe}}
+            {{#java17}}
             sourceCompatibility JavaVersion.VERSION_17
             targetCompatibility JavaVersion.VERSION_17
-            {{/useJakartaEe}}
-            {{^useJakartaEe}}
+            {{/java17}}
+            {{^java17}}
             sourceCompatibility JavaVersion.VERSION_1_8
             targetCompatibility JavaVersion.VERSION_1_8
-            {{/useJakartaEe}}
+            {{/java17}}
         }
 
         // Rename the aar correctly
@@ -84,14 +84,14 @@ if(hasProperty('target') && target == 'android') {
     apply plugin: 'java'
     apply plugin: 'maven-publish'
 
-    {{#useJakartaEe}}
+    {{#java17}}
     sourceCompatibility = JavaVersion.VERSION_17
     targetCompatibility = JavaVersion.VERSION_17
-    {{/useJakartaEe}}
-    {{^useJakartaEe}}
+    {{/java17}}
+    {{^java17}}
     sourceCompatibility = JavaVersion.VERSION_1_8
     targetCompatibility = JavaVersion.VERSION_1_8
-    {{/useJakartaEe}}
+    {{/java17}}
 
     publishing {
         publications {

modules/openapi-generator/src/main/resources/Java/libraries/webclient/pojo.mustache

@@ -29,7 +29,7 @@
 {{#vendorExtensions.x-class-extra-annotation}}
 {{{vendorExtensions.x-class-extra-annotation}}}
 {{/vendorExtensions.x-class-extra-annotation}}
-public class {{classname}} {{#parent}}extends {{{.}}} {{/parent}}{{#vendorExtensions.x-implements}}{{#-first}}implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{#-last}} {{/-last}}{{/vendorExtensions.x-implements}}{
+public {{>sealed}}class {{classname}} {{#parent}}extends {{{.}}} {{/parent}}{{#vendorExtensions.x-implements}}{{#-first}}implements {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{#-last}} {{/-last}}{{/vendorExtensions.x-implements}}{{>permits}}{
 {{#serializableModel}}
   private static final long serialVersionUID = 1L;
 

modules/openapi-generator/src/main/resources/Java/libraries/webclient/pom.mustache

@@ -45,14 +45,14 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.13.0</version>
                 <configuration>
-                {{#useJakartaEe}}
+                {{#java17}}
                     <source>17</source>
                     <target>17</target>
-                {{/useJakartaEe}}
-                {{^useJakartaEe}}
+                {{/java17}}
+                {{^java17}}
                     <source>1.8</source>
                     <target>1.8</target>
-                {{/useJakartaEe}}
+                {{/java17}}
                 </configuration>
             </plugin>
             <plugin>

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

@@ -1,5 +1,5 @@
 {{>additionalOneOfTypeAnnotations}}{{>generatedAnnotation}}{{>typeInfoAnnotation}}{{>xmlAnnotation}}
-public interface {{classname}} {{#vendorExtensions.x-implements}}{{#-first}}extends {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}} {
+public {{>sealed}}interface {{classname}} {{#vendorExtensions.x-implements}}{{#-first}}extends {{{.}}}{{/-first}}{{^-first}}, {{{.}}}{{/-first}}{{/vendorExtensions.x-implements}}{{>permits}}{
     {{#discriminator}}
     public {{propertyType}} {{propertyGetter}}();
     {{/discriminator}}