fix: #21329 Java Native, Provide Null Check before toString on param variables (#21330)

* fix: #21329 Java Native, Provide Null Check before toString on param variables

* #21329 - Samples Generated

Author: duttonw

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

@@ -484,7 +484,9 @@ public class {{classname}} {
         hasFiles = true;
         {{/isFile}}
         {{^isFile}}
-        multiPartBuilder.addTextBody("{{{baseName}}}", {{paramName}}.get(i).toString());
+        if ({{paramName}}.get(i) != null) {
+            multiPartBuilder.addTextBody("{{{baseName}}}", {{paramName}}.get(i).toString());
+        }
         {{/isFile}}
     }
     {{/isArray}}
@@ -494,7 +496,9 @@ public class {{classname}} {
     hasFiles = true;
     {{/isFile}}
     {{^isFile}}
-    multiPartBuilder.addTextBody("{{{baseName}}}", {{paramName}}.toString());
+    if ({{paramName}} != null) {
+        multiPartBuilder.addTextBody("{{{baseName}}}", {{paramName}}.toString());
+    }
     {{/isFile}}
     {{/isArray}}
     {{/formParams}}

samples/client/echo_api/java/native/src/main/java/org/openapitools/client/api/FormApi.java

@@ -260,7 +260,9 @@ private HttpRequest.Builder testFormObjectMultipartRequestBuilder(@javax.annotat
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("marker", marker.toString());
+    if (marker != null) {
+        multiPartBuilder.addTextBody("marker", marker.toString());
+    }
     HttpEntity entity = multiPartBuilder.build();
     HttpRequest.BodyPublisher formDataPublisher;
     if (hasFiles) {

samples/client/petstore/java/native-async/src/main/java/org/openapitools/client/api/PetApi.java

@@ -847,7 +847,9 @@ private HttpRequest.Builder uploadFileRequestBuilder(@javax.annotation.Nonnull L
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    if (additionalMetadata != null) {
+        multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    }
     multiPartBuilder.addBinaryBody("file", _file);
     hasFiles = true;
     HttpEntity entity = multiPartBuilder.build();
@@ -983,7 +985,9 @@ private HttpRequest.Builder uploadFileWithRequiredFileRequestBuilder(@javax.anno
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    if (additionalMetadata != null) {
+        multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    }
     multiPartBuilder.addBinaryBody("requiredFile", requiredFile);
     hasFiles = true;
     HttpEntity entity = multiPartBuilder.build();

samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/PetApi.java

@@ -814,7 +814,9 @@ private HttpRequest.Builder uploadFileRequestBuilder(@jakarta.annotation.Nonnull
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    if (additionalMetadata != null) {
+        multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    }
     multiPartBuilder.addBinaryBody("file", _file);
     hasFiles = true;
     HttpEntity entity = multiPartBuilder.build();

samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/PetApi.java

@@ -794,7 +794,9 @@ private HttpRequest.Builder uploadFileRequestBuilder(@javax.annotation.Nonnull L
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    if (additionalMetadata != null) {
+        multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    }
     multiPartBuilder.addBinaryBody("file", _file);
     hasFiles = true;
     HttpEntity entity = multiPartBuilder.build();
@@ -920,7 +922,9 @@ private HttpRequest.Builder uploadFileWithRequiredFileRequestBuilder(@javax.anno
 
     MultipartEntityBuilder multiPartBuilder = MultipartEntityBuilder.create();
     boolean hasFiles = false;
-    multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    if (additionalMetadata != null) {
+        multiPartBuilder.addTextBody("additionalMetadata", additionalMetadata.toString());
+    }
     multiPartBuilder.addBinaryBody("requiredFile", requiredFile);
     hasFiles = true;
     HttpEntity entity = multiPartBuilder.build();