换成了国内的数据库

app/src/main/java/hunnu/sj/raise_money/DataBase/UserService.java

@@ -17,7 +17,7 @@ public class UserService {
         conn = db.getConnection();
         Statement sttmt = null;
         try{
-            sttmt = conn.createStatement();
+            sttmt = conn.createStatement();//SAD
             String sql = "select * from user where username = '"+username+"'";
             PreparedStatement ps = conn.prepareStatement(sql);
             ResultSet rs1 = ps.executeQuery();