Spring MVC中的單選按鈕列表

Question

我有一個表單，它將用戶的姓名和性別作爲輸入數據。實際上，這種輸入形式是以性別命名的。我的豆代碼：

public class Info{ 
    private List<String> names; 
    private List<Sex> sexes; 
} 

public enum Sex{ 
Male, 
Fmale, 
Unknone; 
// 
} 

現在我想形成這樣

<c:forEach begin="0" end="10" varStatus="s"> 
    <tr> 
     <td> <form:input path="names[${s.index}]" /> </td> 
     <td><form:radiobutton path="sexes" value="<%=Sex.Male%>"></td> 
     <td><form:radiobutton path="sexes" value="<%=Sex.Fmale%>"></td> 
     <td><form:radiobutton path="sexes" value="<%=Sex.Unknone%>"></td> 
    </tr> 
    </c:forEach> 

，但運行時項目捕獲該異常

org.springframework.beans.NullValueInNestedPathException: Invalid property ... 

Answer 1

試試這個

<c:forEach begin="0" end="10" varStatus="s"> 
<tr> 
    <td> <form:input path="names[${s.index}]" /> </td> 
    <td><form:radiobutton path="sexes[${s.index}]" value="<%=Sex.Male%>"></td> 
    <td><form:radiobutton path="sexes[${s.index}]" value="<%=Sex.Fmale%>"></td> 
    <td><form:radiobutton path="sexes[${s.index}]" value="<%=Sex.Unknone%>"></td> 
</tr>