import Nullable if required (#21829)

Also allows to override it eg with: <importMapping>Nullable=org.jspecify.annotations.Nullable</importMapping>

Author: parenko

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

@@ -1039,6 +1039,12 @@ public CodegenOperation fromOperation(String path, String httpMethod, Operation
             codegenOperation.imports.addAll(provideArgsClassSet);
         }
 
+        // to prevent inheritors (JavaCamelServerCodegen etc.) mistakenly use it
+        if (getName().contains("spring")) {
+          codegenOperation.allParams.stream().filter(CodegenParameter::notRequiredOrIsNullable).findAny()
+              .ifPresent(p -> codegenOperation.imports.add("Nullable"));
+        }
+
         if (reactive) {
             if (DocumentationProvider.SPRINGFOX.equals(getDocumentationProvider())) {
                 codegenOperation.imports.add("ApiIgnore");

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

@@ -32,7 +32,6 @@ import io.virtualan.annotation.VirtualService;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
 {{/jdk8-no-delegate}}
-import org.springframework.lang.Nullable;
 {{^useResponseEntity}}
 import org.springframework.http.HttpStatus;
 {{/useResponseEntity}}

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

@@ -21,7 +21,6 @@ import io.swagger.annotations.*;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 {{#useResponseEntity}}
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;

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

@@ -7,7 +7,6 @@ import org.springframework.http.MediaType;
 {{#useResponseEntity}}
 import org.springframework.http.ResponseEntity;
 {{/useResponseEntity}}
-import org.springframework.lang.Nullable;
 import org.springframework.web.context.request.NativeWebRequest;
 import org.springframework.web.multipart.MultipartFile;
 {{#reactive}}

modules/openapi-generator/src/main/resources/JavaSpring/libraries/spring-http-interface/api.mustache

@@ -13,7 +13,6 @@ import org.springframework.http.HttpStatus;
 {{#useResponseEntity}}
 import org.springframework.http.ResponseEntity;
 {{/useResponseEntity}}
-import org.springframework.lang.Nullable;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.service.annotation.*;
 import org.springframework.web.multipart.MultipartFile;

samples/client/petstore/spring-cloud-auth/src/main/java/org/openapitools/api/SomeApi.java

@@ -7,7 +7,6 @@
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;

samples/client/petstore/spring-cloud-date-time/src/main/java/org/openapitools/api/DefaultApi.java

@@ -7,11 +7,11 @@
 
 import org.springframework.format.annotation.DateTimeFormat;
 import java.time.LocalDate;
+import org.springframework.lang.Nullable;
 import java.time.OffsetDateTime;
 import io.swagger.annotations.*;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;

samples/client/petstore/spring-cloud-deprecated/src/main/java/org/openapitools/api/PetApi.java

@@ -6,6 +6,7 @@
 package org.openapitools.api;
 
 import org.openapitools.model.ModelApiResponse;
+import org.springframework.lang.Nullable;
 import org.openapitools.model.Pet;
 import io.swagger.v3.oas.annotations.ExternalDocumentation;
 import io.swagger.v3.oas.annotations.Operation;
@@ -21,7 +22,6 @@
 import io.swagger.v3.oas.annotations.media.ExampleObject;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;

samples/client/petstore/spring-cloud-deprecated/src/main/java/org/openapitools/api/StoreApi.java

@@ -21,7 +21,6 @@
 import io.swagger.v3.oas.annotations.media.ExampleObject;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;

samples/client/petstore/spring-cloud-deprecated/src/main/java/org/openapitools/api/UserApi.java

@@ -21,7 +21,6 @@
 import io.swagger.v3.oas.annotations.media.ExampleObject;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.lang.Nullable;
 import org.springframework.http.ResponseEntity;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;