Spring MVC如何将列表中的WordDto传递至POST接口？

我有一个Spring控制器，其中包含一个接收WordDto的POST接口；另有一个GET接口将WordDto列表存入ModelMap并渲染JSP页面。在JSP页面中，我将列表的每个条目展示在表格的一行中，每行还有一个按钮，需要调用POST接口并传递该行对应的WordDto，但我不知道如何正确地将行中的WordDto传递给POST接口。

接口代码 #

@GetMapping("/generate")
public String generateWords(ModelMap model, @RequestParam(value = "language", defaultValue = "-1", required = false) long language, @RequestParam(value = "amount", defaultValue = "-1", required = false) int amount)
{
    model.put("language", language);
    model.put("amount", amount);

    LanguageData languageData = languageService.getLanguageData(language);

    model.put("languageName", languageData.getName());
    model.put("words", generationService.generateWords(language, amount));

    return "list-words";
}

@PostMapping("word")
public String saveWord(ModelMap model, HttpServletRequest request, @Valid WordDto singleWord)
{
    translationService.saveOrGetWord(singleWord);

    return "redirect:" + request.getHeader("Referer");
}

JSP页面代码 #

<body>
    <%--@elvariable id="languageName" type="java.lang.String"--%>
    <h1>Generated words with '${languageName}'</h1>
    <table class="table">
        <thead>
        <tr>
            <th>Word</th>
        </tr>
        </thead>
        <tbody>
        <%--@elvariable id="words" type="java.util.List"--%>
        <c:forEach items="${words}" var="singleWord">
            <tr>
                <td>
                        ${singleWord.word}
                </td>
                <td>
                    <form:form method="post" action="word" modelAttribute="singleWord.word">
                        <form:input type="hidden" path="languageId"/>
                        <form:input type="text" path="word"/>
                    </form:form>
                </td>
            </tr>
        </c:forEach>
        </tbody>
    </table>
</body>

核心问题是JSP中Spring表单标签的modelAttribute配置错误，导致无法正确绑定当前行的WordDto对象，以下是修正步骤：

1. 引入必要标签库
   在JSP页面开头添加Spring表单和JSTL标签库声明，否则表单标签无法生效：

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

2. 修正表单绑定配置
   将form:form的modelAttribute改为当前循环的singleWord对象，同时为action添加上下文路径，避免请求地址错误：

<form:form method="post" action="${pageContext.request.contextPath}/word" modelAttribute="singleWord">

3. 完善表单字段与提交按钮
   根据需求用隐藏或输入字段传递WordDto的所有属性，并添加提交按钮触发请求：

<td>
    <form:form method="post" action="${pageContext.request.contextPath}/word" modelAttribute="singleWord">
        <form:hidden path="languageId"/>
        <form:hidden path="word"/>
        <button type="submit">保存</button>
    </form:form>
</td>

如果需要让用户编辑word字段，将<form:hidden path="word"/>替换为<form:input path="word"/>即可。

4. 确保WordDto类的正确性
   WordDto必须包含所有绑定属性的getter和setter方法，否则Spring MVC无法完成参数绑定，示例结构：

public class WordDto {
    private Long languageId;
    private String word;

    public WordDto() {}

    public Long getLanguageId() { return languageId; }
    public void setLanguageId(Long languageId) { this.languageId = languageId; }
    public String getWord() { return word; }
    public void setWord(String word) { this.word = word; }
}

修改后的完整JSP代码 #

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE html>
<html>
<head>
    <title>Generated Words</title>
</head>
<body>
    <%--@elvariable id="languageName" type="java.lang.String"--%>
    <h1>Generated words with '${languageName}'</h1>
    <table class="table">
        <thead>
        <tr>
            <th>Word</th>
            <th>操作</th>
        </tr>
        </thead>
        <tbody>
        <%--@elvariable id="words" type="java.util.List"--%>
        <c:forEach items="${words}" var="singleWord">
            <tr>
                <td>${singleWord.word}</td>
                <td>
                    <form:form method="post" action="${pageContext.request.contextPath}/word" modelAttribute="singleWord">
                        <form:hidden path="languageId"/>
                        <form:hidden path="word"/>
                        <button type="submit">保存单词</button>
                    </form:form>
                </td>
            </tr>
        </c:forEach>
        </tbody>
    </table>
</body>
</html>

内容的提问来源于stack exchange，提问作者Fi0x