java - 在 @ModelAttribute 注释方法中返回 Spring 模型

Question

我可以在使用@ModelAttribute 注释的方法中使用 Spring 模型作为模型吗？我收到一条错误消息，指出无法在模型中找到该属性。

这是我将对象添加到模型的方法:

@ModelAttribute("survivor")
public Model getSurvivors(Model m) {
    m.addAttribute("decedent", new Decedent());

    return m;
}

这是渲染方法。它打印“模型包含 decedent=true”

@RenderMapping(params="render=survivors")
public String showSurvivors(Model model, RenderRequest request, RenderResponse response) throws Exception {
    logger.info("in showSurvivors");
    logger.debug("model contains decedent={}, mode.containsAttribute("decedent");
    return "survivors";
}

这是jsp:

<form:form commandName="survivor" action="${submitAction}">
<form:input path="decedent.firstName" />

错误:

org.springframework.web.servlet.tags.RequestContextAwareTag doStartTag Invalid property 'decedent' of bean class [org.springframework.validation.support.BindingAwareModelMap]: Bean property 'decedent' is not readable or has an invalid getter method: Does the return type of the getter match the parameter type of the setter?

Answer 1

你本质上是这样做的:

model.addAttribute("survivor", model);

您在 form:input 中看到的问题是它期望在不存在的模型上使用 getter decedent。解决方法是在普通 Map 之上使用另一种包装器类型:

public class MyCommand{
    private Map<String, Decedent> decedents;
...getters and setters.
}

..

model.addAttribute("survivor", ..); //Add MyCommand type..

..

<form:form commandName="survivor" action="${submitAction}">
<form:input path="decedents['decedent']" />