fix

zjugis-business/src/main/java/com/zjugis/business/service/impl/ContractServiceImpl.java

@@ -153,7 +153,7 @@ public class ContractServiceImpl implements ContractService{
             BeanUtils.copyProperties(dbParent, r);
             if(!map.isEmpty()) {
                 List<Contract> children = map.get(r.getId());
-                if(!children.isEmpty()){
+                if(children != null && !children.isEmpty()){
                     r.setChildren(children.stream().map((contract) -> {
                         ContractChildResponse child = new ContractChildResponse();
                         BeanUtils.copyProperties(contract, child);