diff --git a/src/main/java/com/codesdream/ase/model/activity/Activity.java b/src/main/java/com/codesdream/ase/model/activity/Activity.java
index 2a0b4f2..6359756 100644
--- a/src/main/java/com/codesdream/ase/model/activity/Activity.java
+++ b/src/main/java/com/codesdream/ase/model/activity/Activity.java
@@ -137,11 +137,10 @@ public class Activity {
 
     //提前提醒时间
     @Column(name = "remind_time", nullable = true)
-    @Temporal(TemporalType.TIMESTAMP)
     private LocalDateTime remindTime;
 
     //附件组(名字)
-    @ElementCollection(targetClass = java.lang.String.class)
+    @ElementCollection(targetClass = String.class)
     private List<String> enclosures;
 
     //主要负责人
diff --git a/src/main/java/com/codesdream/ase/validator/TestNullValueValidator.java b/src/main/java/com/codesdream/ase/validator/TestNullValueValidator.java
new file mode 100644
index 0000000..a7c4a84
--- /dev/null
+++ b/src/main/java/com/codesdream/ase/validator/TestNullValueValidator.java
@@ -0,0 +1,27 @@
+package com.codesdream.ase.validator;
+
+import com.codesdream.ase.model.activity.Activity;
+import javafx.beans.binding.ObjectExpression;
+
+import java.lang.reflect.Field;
+
+public class TestNullValueValidator {
+
+    public static void main(String[] args){
+        Activity activity = new Activity();
+        TestNullValueValidator.run(activity);
+
+    }
+
+    static void run(Object object){
+        Field[] fields = object.getClass().getDeclaredFields();
+        for (Field field : fields){
+            String name = field.getName();
+            name = name.substring(0,1).toUpperCase()+name.substring(1);
+            String type = field.getGenericType().toString();
+            System.out.println("name: " + name);
+            System.out.println("Type: " + type);
+            System.out.println();
+        }
+    }
+}