add charge

rankin-user-service/src/main/java/cn/rankin/userservice/repository/MerchantRepository.java

@@ -26,6 +26,6 @@ public interface MerchantRepository  extends BasicJpaRepository<Merchant, String
     int updateStatusById(@Param("id") String id, @Param("status") BaseStatusEnum status);
 
 	@Modifying
-    @Query(value = "update Merchant m set m.balance = m.balance + ?2 where m.balance - ?2 > 0 and m.id = ?1")
+    @Query(value = "update Merchant m set m.balance = m.balance + ?2 where m.balance + ?2 > 0 and m.id = ?1")
     Integer updateBalance(String merchantId, BigDecimal quantity);
 }

rankin-user-service/src/main/java/cn/rankin/userservice/service/PayingService.java

@@ -32,7 +32,8 @@ public class PayingService {
             return APIResult.error(UserServiceAPICode.NOT_EXISTS);
         }
 
-        if (merchant.getBalance().compareTo(quantity) < 0) {
+        BigDecimal balance = merchant.getBalance();
+        if (balance.add(quantity).compareTo(BigDecimal.ZERO) < 0) {
             return APIResult.error(UserServiceAPICode.MONEY_NOT_ENOUGH);
         }