Spring 3.0 MVC绑定嵌套对象
问题描述:
为什么spring没有绑定我的嵌套对象上的值?Spring 3.0 MVC绑定嵌套对象
RegistrationBean上的SecurityQuestion对象的问题和答案分别设置为null,null,尽管在窗体中使用视图中的bean表示法进行设置。
豆类:
public class SecurityQuestion {
SecurityQuestionType type;
String answer;
}
public class RegistrationBean {
@Valid
SecurityQuestion securityQuestion;
String name;
public SecurityQuestionType[] getSecurityQuestionOptions() {
return SecurityQuestionType.values();
}
}
查看:
<form:form modelAttribute="registrationBean" method="POST">
<form:select id="securityQuestion" path="securityQuestion.question">
<c:forEach var="securityQuestionOption" items="${securityQuestionOptions}">
<form:option value="${securityQuestionOption}">${securityQuestionOption</form:option>
</c:forEach>
</form:select>
<form:input id="securityAnswer" path="securityQuestion.answer" />
<form:input id="name" path="name" />
</form:form>
控制器:
@RequestMapping(value = URL_PATTERN, method = RequestMethod.POST)
public ModelAndView submit(@Valid final RegistrationBean registrationBean) {
// registrationBean.getSecurityQuestion().getQuestion() == null
// registrationBean.getSecurityQuestion().getAnswer() == null
}
解决方案
所有的bean必须有getter/setter的所有字段。 Spring使用默认的构造函数,然后使用setter从视图中改变对象。
答
你可以尝试给RegistrationBean一个合适的getter/setter。
public class RegistrationBean {
@Valid
SecurityQuestion securityQuestion;
String name;
public SecurityQuestion getSecurityQuestion(){
return securityQuestion;
}
public void setSecurityQuestion(SecurityQuestion q){
this.securityQuestion = q;
}
public SecurityQuestionType[] getSecurityQuestionOptions() {
return SecurityQuestionType.values();
}
}
问题属性在SecurityQuestion中丢失(我想这是因为你忘记了写在问题中)。你有属性的getter和setter吗? – Javi 2010-12-08 19:36:20