[FIXED] Thymeleaf with springboot, error trying to check if list is empty now working

Issue

i'm trying to check if my list called listPersons is empty or not, but when i check i got an error like this:

Caused by: org.attoparser.ParseException: Exception evaluating SpringEL expression: .... Caused by: org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "#lists.isEmpty(listPersons" (template: "index" - line 15, col 8)

I have tried this:

<h2 th:if="${#lists.isEmpty(listPersons)}">No hay personas</h2>
<div th:if="${#!lists.isEmpty(listPersons)}">

and this:

 ${listPersons.isEmpty()}

But none of the options are working. I'm using thymeleaf-3.0.15 and springboot version 2.7.2

In my Java method i have this line:

model.addAttribute("listPersons", personaService.getAll());

Solution

You are not using the conditional statements correctly, hence you are getting the SPEL error

<div th:if="${#!lists.isEmpty(listPersons)}">

Use the below for your condition

<div th:if="${not #lists.isEmpty(listPersons)}">

Refer https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#conditional-evaluation

to get more insights.

Answered By - Rishal
Answer Checked By - Clifford M. (JavaFixing Volunteer)