Error resolving template [forms/form_layouts]

Controller层

@GetMapping(value = "/form_layouts")
    public String form_layouts() {
        return "forms/form_layouts";
}

<li class="menu-list"><a href=""><i class="fa fa-tasks"></i> <span>Forms</span></a>
    <ul class="sub-menu-list">
         <li><a th:href="@{/form_layouts}"> Form Layouts</a></li>
         <li><a th:href="@{/form_advanced_components}"> Advanced Components</a></li>
         <li><a th:href="@{/form_wizard}"> Form Wizards</a></li>
         <li><a th:href="@{/form_validation}"> Form Validation</a></li>
         <li><a th:href="@{/editors}"> Editors</a></li>
         <li><a th:href="@{/inline_editors}"> Inline Editors</a></li>
         <li><a th:href="@{/pickers}"> Pickers</a></li>
         <li><a th:href="@{/dropzone}"> Dropzone</a></li>
    </ul>
</li>

我的form_layouts.html就是放在templates下的form文件夾中，报错显示controller的返回有问题，该怎么解决？

 重启了Ideal解决了！？