无效的属性'redeemVoucherForm' bean 类 [my.testapp.forms.RedeemVoucherForm]

Question

出现错误:

Invalid property 'redeemVoucherForm' of bean class [my.testapp.forms.RedeemVoucherForm]: Bean property 'redeemVoucherForm' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

RedeemVoucherForm.java:

package my.testapp.forms;
public class RedeemVoucherForm {
    private String voucherCode;
    public String getVoucherCode() {
        return voucherCode;
    }
    public void setVoucherCode(String voucherCode) {
        this.voucherCode = voucherCode;
    }
}

在我的PageController.java中，我添加了存在的模型redeemVoucherForm，当我调用方法model. containsattribute ("redeemVoucherForm"):

@RequestMapping(method = RequestMethod.GET)
public String showPage(final Model model) {
    ...
    model.addAttribute("redeemVoucherForm", new RedeemVoucherForm());
    ...
    return REDIRECT_PAGE_URL;
}
@RequestMapping(value = "/redeem-voucher", method = RequestMethod.POST)
public String redeemVoucher(@Valid final RedeemVoucherForm redeemVoucherForm, final BindingResult bindingResult, final RedirectAttributes redirectModel, final Model model, HttpServletRequest request) {
    LOG.debug("<POST> Redeeming voucher...");
    return REDIRECT_PAGE_URL;
}

pageDisplay.jsp:

<c:url value="/page/redeem-voucher" var="redeemVoucherAction" />
<form:form action="${redeemVoucherAction}" method="post" commandName="redeemVoucherForm">
        <form:input cssClass="form-control" type="text" path="redeemVoucherForm.voucherCode"/>
        <button type="submit" class="btn btn-primary btn-block checkoutButton">
            <spring:theme text="Redeem Voucher"/>
        </button>
</form:form>

当我设置模型redeemVoucherForm时，我还能错过什么?

Answer 1

我相信这行

    <form:input cssClass="form-control" type="text" path="redeemVoucherForm.voucherCode"/>

应该

    <form:input cssClass="form-control" type="text" path="voucherCode"/>

<form:input>的path元素应该相对于您设置为<form:form>的commandName的对象。在你的例子中，这个对象是你的类RedeemVoucherForm的一个实例。

如果您将路径设置为redeemVoucherForm.voucherCode, Spring将在您的类RedeemVoucherForm上查找redeemVoucherForm属性。它期望this的值是一个具有voucherCode属性的对象，它可以从中读取表单值。当然，redeemVoucherForm属性不存在，因此会出现错误。