update

src/main/java/com/gogirl/shared/order/StoreTechnicianPeriod.java

@@ -35,6 +35,9 @@ public class StoreTechnicianPeriod implements Serializable {
      */
     private String grade;
 
+    public StoreTechnicianPeriod() {
+
+    }
 
 
     public StoreTechnicianPeriod(List<Period> periodList, StoreTechnician storeTechnician) {