diff --git a/youchain-system/src/main/java/com/youchain/utils/PostRequestSigner.java b/youchain-system/src/main/java/com/youchain/utils/PostRequestSigner.java
index cf15629..750b6fc 100644
--- a/youchain-system/src/main/java/com/youchain/utils/PostRequestSigner.java
+++ b/youchain-system/src/main/java/com/youchain/utils/PostRequestSigner.java
@@ -1,5 +1,6 @@
 package com.youchain.utils;
 
+import com.youchain.exception.BadRequestException;
 import lombok.extern.slf4j.Slf4j;
 
 import java.io.UnsupportedEncodingException;
@@ -28,7 +29,7 @@ public class PostRequestSigner {
             Map<String, String> allParams = new TreeMap<>(); // TreeMap会自动按key升序排序
 
             // 添加JSON Body参数
-            if (jsonBody != null && !jsonBody.isEmpty()) {
+            if (StringUtils.isNotBlank(jsonBody)) {
                 allParams.put("jsonBody", jsonBody);
             }
 
@@ -55,7 +56,7 @@ public class PostRequestSigner {
             return sha256(signSource.toString());
 
         } catch (Exception e) {
-            throw new RuntimeException("生成签名失败: " + e.getMessage(), e);
+            throw new BadRequestException("生成签名失败: " + e.getMessage());
         }
     }