修复Excel转PDF转换边界问题

server/src/main/java/cn/nianxx/thhotel/platform/documentconversion/control/DocumentConversionControllerAdvice.java

@@ -2,10 +2,12 @@ package cn.nianxx.thhotel.platform.documentconversion.control;
 
 import cn.nianxx.thhotel.platform.documentconversion.common.result.DocumentConversionErrorResponse;
 import cn.nianxx.thhotel.platform.documentconversion.service.DocumentConversionException;
+import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.MissingServletRequestParameterException;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.bind.annotation.RestControllerAdvice;
+import org.springframework.web.multipart.MaxUploadSizeExceededException;
 import org.springframework.web.multipart.support.MissingServletRequestPartException;
 
 /**
@@ -34,4 +36,16 @@ public class DocumentConversionControllerAdvice {
                         "DOCUMENT_CONVERSION_FILE_REQUIRED",
                         "请上传 Excel 文件。"));
     }
+
+    /**
+     * 转换 Spring multipart 框架层上传大小超限异常。
+     */
+    @ExceptionHandler(MaxUploadSizeExceededException.class)
+    public ResponseEntity<DocumentConversionErrorResponse> handleMaxUploadSizeExceeded(
+            MaxUploadSizeExceededException exception) {
+        return ResponseEntity.status(HttpStatus.PAYLOAD_TOO_LARGE)
+                .body(new DocumentConversionErrorResponse(
+                        "DOCUMENT_CONVERSION_FILE_TOO_LARGE",
+                        "上传的 Excel 文件超过大小限制。"));
+    }
 }