fix message role compare

Author: xiongbinbin

src/main/java/com/alibaba/dashscope/aigc/imagegeneration/ImageGeneration.java

@@ -314,7 +314,7 @@ private void preprocessInput(ImageGenerationParam param)
     boolean hasUpload = false;
     OSSUploadCertificate certificate = null;
     for (ImageGenerationMessage msg : param.getMessages()) {
-      if (msg.getRole().equals(Role.USER)) {
+      if (msg.getRole().equals(Role.USER.getValue())) {
         boolean isUpload;
         PreprocessMessageInput.PreprocessResult result =
             PreprocessMessageInput.preProcessMultiModalMessageInputs(

src/main/java/com/alibaba/dashscope/aigc/multimodalconversation/MultiModalConversation.java

@@ -236,7 +236,7 @@ private void preprocessInput(MultiModalConversationParam param)
       boolean isUpload = false;
       if (msg instanceof MultiModalConversationMessage) {
         MultiModalConversationMessage realMsg = (MultiModalConversationMessage)msg;
-        if (realMsg.getRole().equals(Role.USER)) {
+        if (realMsg.getRole().equals(Role.USER.getValue())) {
           PreprocessMessageInput.PreprocessResult result =
               PreprocessMessageInput.preProcessMessageInputs(
                   param.getModel(),
@@ -248,7 +248,7 @@ private void preprocessInput(MultiModalConversationParam param)
         }
       } else {
         MultiModalMessage realMsg = (MultiModalMessage) msg;
-        if (realMsg.getRole().equals(Role.USER)) {
+        if (realMsg.getRole().equals(Role.USER.getValue())) {
           PreprocessMessageInput.PreprocessResult result =
               PreprocessMessageInput.preProcessMultiModalMessageInputs(
                   param.getModel(), (MultiModalMessage) msg, param.getApiKey(), certificate);