更改返回标签

src/com/hellogithub/dao/UserDao.java

@@ -131,18 +131,19 @@ public class UserDao {
             String sql = "select searchHistory from user where userName=? and isValid = 1";
             userEntity  = runner.query(conn, sql, new BeanHandler<>(userEntity.class),name);
             l = userEntity.getSearchHistory().split(";");
-
+            List<String> sss= new ArrayList<>(Arrays.asList(l));
-            for(int i=0;i<l.length;i++)
+            for(int i=0;i<sss.size();i++)
             {
-                if(l[i].equals(str))
+                if(sss.get(i).equals(str))
                 {
-                    l[i]="";
+                    sss.remove(i);
                     break;
                 }
             }
-            label = String.join(";",l)+";";
+            if(sss.size()!=0)
-            if(l.length == 1)
             {
+                label = String.join(";",sss)+";";
+            }else{
                 label="";
             }
             sql="UPDATE user SET searchHistory = ? WHERE userName= ?";

src/com/hellogithub/servlet/selectUserLabelServlet.java

@@ -44,7 +44,7 @@ public class selectUserLabelServlet extends HttpServlet {
             String name = userEntity.getUserName();
             List<String> stringList = userService.selectLabel(name);
             if(stringList.get(0).equals("无搜索历史")){
-                writer.println(jsonString);
+                writer.println("null");
             }
             else{
                 jsonString = JSONObject.toJSONString(stringList);