From 4ead89764a5431322ec2dd031b954e0fedac4fb8 Mon Sep 17 00:00:00 2001
From: User_cyk <1020691186@qq.com>
Date: Tue, 11 Jul 2023 13:58:26 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BF=AE=E6=94=B9retUser=E6=8E=A5=E5=8F=A3?=
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---
 src/com/hellogithub/servlet/retUserServlet.java | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/com/hellogithub/servlet/retUserServlet.java b/src/com/hellogithub/servlet/retUserServlet.java
index 865bfa4..b968f42 100644
--- a/src/com/hellogithub/servlet/retUserServlet.java
+++ b/src/com/hellogithub/servlet/retUserServlet.java
@@ -42,6 +42,10 @@ public class retUserServlet extends HttpServlet {
 
         PrintWriter writer = resp.getWriter();
         String username = req.getParameter("username");
+        if(username ==null)
+        {
+            return ;
+        }
         String jsonString="";
         jsonString = JSONObject.toJSONString(userService.selectUserByName(username));
         if(jsonString.equals(""))