证据文件获取异常时需抛出

src/main/java/com/supervision/police/service/impl/CaseEvidenceServiceImpl.java

@@ -307,12 +307,12 @@ public class CaseEvidenceServiceImpl extends ServiceImpl<CaseEvidenceMapper, Cas
         CaseEvidence caseEvidence = getById(evidenceId);
         if (caseEvidence == null) {
             log.error("证据不存在");
-            return;
+            throw new IllegalArgumentException("证据不存在");
         }
         List<EvidenceFileDTO> evidenceFiles = evidenceFileService.listFileInfo(List.of(evidenceId));
         if (evidenceFiles.isEmpty()) {
             log.error("证据id:【{}】不存在证据文件", evidenceId);
-            return;
+            throw new IllegalArgumentException("证据不存在证据文件");
         }
         try {
             // 根据rank升序排序