完成了修改

src/backend/dao/impl/QuestionsDao.java

@@ -82,7 +82,10 @@ public class QuestionsDao {
             stmt.setString(1, question.getName());
             stmt.setString(2, question.getDescription());
             stmt.setString(3, question.getAnswer());
-            stmt.setInt(4, question.getFrequency());
+            if(question.getFrequency()==null)
+                stmt.setInt(4, 0);
+            else
+                stmt.setInt(4, question.getFrequency());
             row = stmt.executeUpdate();
             stmt.close();
 
@@ -114,20 +117,23 @@ public class QuestionsDao {
         }
         return row > 0;
     }
-    public boolean updata(Questions question){
+    public boolean update(Questions question){
         int row = 0;
         //1. 从连接池中拿到连接
         Connection conn = DBConnectionPool.getConnection();
         if(conn==null)
             return false;
         //2. 创建Statement对象
-        String sql = "updata questions set name = ?,description = ?,answer = ?,frequency=? where id = ?";
+        String sql = "update questions set name = ?,description = ?,answer = ?,frequency=? where id = ?";
         try{
             PreparedStatement stmt = conn.prepareStatement(sql);
             stmt.setString(1, question.getName());
             stmt.setString(2, question.getDescription());
             stmt.setString(3, question.getAnswer());
-            stmt.setInt(4, question.getFrequency());
+            if(question.getFrequency()==null)
+                stmt.setInt(4, 0);
+            else
+                stmt.setInt(4, question.getFrequency());
             stmt.setInt(5, question.getId());
             row = stmt.executeUpdate();
             stmt.close();