java - Thymeleaf 嵌套each 和数组索引

Question

我有一个嵌套的each 结构，它循环穿过一棵树。 html代码如下:

<div th:each="group : ${groups}" class="row corp-teams-group-row">
    <h2 th:text="'- ' + ${group.name}">GROUP NAME</h2>
    <div th:each="team : ${group.teams}" class="row corp-teams-teams-row">
        <h2 th:text="'- ' + ${team.name}">TEAM NAME</h2>
        <div class="col-xs-6 corp-man-wrapper corp-admin-wrapper">
            <div class="corp-user-image-container">
                <div class="corp-user-image-wrapper">
                    <img th:src="${team.users[0].image}">
                </div>
                <div class="corp-bugcount"><span th:text="${team.users[0].score}"></span></div>
            </div>
            <div class="corp-user-data-container">
                <h2 th:text="${team.users[0].name} + ' ' + ${team.users[0].surname}"></h2>
                <div class="corp-user-email" th:text="${team.users[0].email}"></div>
            </div>
        </div>
        <div class="col-xs-6 corp-man-wrapper">
            <h3 th:text="${team.newFeatureCount}"></h3>
            <h3 th:text="${team.defectCount}"></h3>
        </div>
        <div th:each="user : ${team.users}" class="col-xs-6 corp-man-wrapper">
            <div class="corp-user-image-container">
                <div class="corp-user-image-wrapper">
                    <img th:src="${user.image}">
                </div>
                <div class="corp-bugcount"><span th:text="${user.score}"></span></div>
            </div>
            <div class="corp-user-data-container">
                <h2 th:text="${user.name} + ' ' + ${user.surname}"></h2>
                <div class="corp-user-email" th:text="${user.email}"></div>
            </div>
        </div>
    </div>
</div>

管理员用户是每个用户数组的第 0 个索引。但达到它的符号显然失败了。我可以确认后端数据是正确的。当此代码在服务器上运行时，我收到此错误:

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.thymeleaf.exceptions.TemplateProcessingException: Exception evaluating SpringEL expression: "team.users[0].score" (teams)

我无法弄清楚这段代码有什么问题，并且网上没有类似的示例可以解决这个问题。谢谢。

Answer 1

正如评论中提到的:异常的原因是

"org.springframework.expression.spel.SpelEvaluationException‌​: EL1025E:(pos 10): The collection has '0' elements, index '0' is invalid"

如果 team.users 可以有零个元素，只需添加一个 th:if 条件即可。