improve urlencoded body handling (#412)

Author: hauner

src/main/kotlin/io/openapiprocessor/spring/model/RequestBody.kt

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2026 https://github.com/openapi-processor/openapi-processor-spring
+ * PDX-License-Identifier: Apache-2.0
+ */
+
+package io.openapiprocessor.spring.model
+
+import io.openapiprocessor.core.model.APPLICATION_FORM_URLENCODED
+import io.openapiprocessor.core.model.datatypes.DataType
+import io.openapiprocessor.core.model.RequestBody as RequestBodyCore
+
+class RequestBody(
+    name: String,
+    contentType: String,
+    dataType: DataType,
+    required: Boolean = false,
+    deprecated: Boolean = false,
+    description: String? = null
+) : RequestBodyCore(name, contentType, dataType, required, deprecated, description) {
+
+    /**
+     * controls if a _request body_ parameter should have a {@code @RequestBody} annotation.
+     */
+    override val withAnnotation: Boolean
+        get() {
+            return contentType != APPLICATION_FORM_URLENCODED
+        }
+}

src/main/kotlin/io/openapiprocessor/spring/processor/SpringFramework.kt

@@ -8,10 +8,12 @@ package io.openapiprocessor.spring.processor
 import io.openapiprocessor.core.framework.FrameworkBase
 import io.openapiprocessor.core.model.datatypes.DataType
 import io.openapiprocessor.core.model.parameters.Parameter
-import io.openapiprocessor.core.parser.MultipartParameter as MultipartParserParameter
-import io.openapiprocessor.core.parser.Parameter as ParserParameter
+import io.openapiprocessor.spring.model.RequestBody
 import io.openapiprocessor.spring.model.parameters.MultipartParameter
 import io.openapiprocessor.spring.model.parameters.QueryParameter
+import io.openapiprocessor.core.parser.MultipartParameter as MultipartParserParameter
+import io.openapiprocessor.core.parser.Parameter as ParserParameter
+import io.openapiprocessor.core.parser.RequestBody as ParserRequestBody
 
 /**
  * Spring model factory.
@@ -41,4 +43,14 @@ class SpringFramework: FrameworkBase() {
             mpp.contentType
         )
     }
+
+    override fun createRequestBody(contentType: String, requestBody: ParserRequestBody, dataType: DataType): RequestBody {
+        return RequestBody(
+            "body",
+            contentType,
+            dataType,
+            requestBody.getRequired(),
+            false,
+            requestBody.description)
+    }
 }

src/main/kotlin/io/openapiprocessor/spring/writer/java/ParameterAnnotationWriter.kt

@@ -26,6 +26,10 @@ class ParameterAnnotationWriter(private val annotations: FrameworkAnnotations)
     }
 
     private fun createRequestBodyAnnotation(requestBody: RequestBody): String {
+        if (! requestBody.withAnnotation) {
+            return ""
+        }
+
         var annotation = getAnnotationName(requestBody)
 
         // required is default, so add required only if the parameter is not required

src/testInt/resources/tests/params-request-body-form-urlencoded/outputs/api/Api.java

@@ -17,7 +17,7 @@ void postFooParams(
             @RequestParam(name = "bar") String bar);
 
     @ResponseStatus(HttpStatus.NO_CONTENT)
-    @PostMapping(path = "/foo/object")
+    @PostMapping(path = "/foo/object", consumes = {"application/x-www-form-urlencoded"})
     void postFooObject(Foo body);
 
 }