我已经浏览了很多这种性质的示例，并提出了本网站的解决方案，但其中提供的解决方案都不适用于我的问题。我相信，当发送到控制器的信息被形成时，会显示此错误消息400。我花了最近两天的时间交叉推荐到我过去工作的另一个项目，这项工作有效，但我无法解决问题。
@RequestMapping(value = {"/", "/home"}, method = RequestMethod.GET)
public String homePage(ModelMap model) {
model.addAttribute("user", getPrincipal());
Catalog catalog = catalogService.getCatalogByCategory(Catalog.CatalogCategory.ALL);
model.addAttribute("catalog", catalog);
return "welcome";
}
这将数据发送到我的JSP上的JSTL Spring表单，如下所示：
<form:form method="POST" modelAttribute="catalog">
<form:hidden path="id"/>
<form:hidden path="name"/>
<form:hidden path="category"/>
<form:hidden path="orderItems"/>
<div id="products" class="row list-group">
<c:forEach var="orderItem" items="${catalog.orderItems}">
<div class="item col-xs-4 col-lg-4">
<div class="thumbnail">
<img class="group list-group-image" src="http://placehold.it/400x250/000/fff" alt=""/>
<div class="caption">
<h4 class="group inner list-group-item-heading">
${orderItem.name}</h4>
<p class="group inner list-group-item-text">
${orderItem.description}
</p>
<div class="row">
<div class="col-xs-12 col-md-6">
<p class="lead">
R ${orderItem.price}</p>
</div>
<div class="col-xs-12 col-md-6">
<label for="${orderItem.id}" class="btn btn-primary">Add to Cart <input
type="checkbox" id="${orderItem.id}" name="orderItem.addedToCart"
class="badgebox"><span class="badge">✓</span></label>
</div>
</div>
</div>
</div>
</div>
</c:forEach>
</div>
<div class="row">
<div class="form-group">
<div class="col-sm-12 pull-right">
</div>
<div class="col-sm-2 pull-right">
<input type="submit"
class="btn btn-default btn-block btn-primary"
value="Next" name="action" formmethod="POST"
formaction="confirmList"/>
</div>
</div>
</div>
</form:form>`
此时我将表单提交给我的控制器中的以下监听器：
@RequestMapping(value = "/confirmList", method = RequestMethod.POST)
public String confirmList(@ModelAttribute Catalog catalog, @ModelAttribute String numberOfItemsAdded) {
List<OrderItem> selectedItems = new ArrayList<OrderItem>();
for (OrderItem orderItem : catalog.getOrderItems()) {
if (orderItem.isAddedToCart()) {
selectedItems.add(orderItem);
}
}
//model.addAttribute("numberOfItemsAdded", selectedItems.size());
return "welcome";
}
就是这样，执行流程甚至没有回到我的控制器。令人疲惫的错误因为我真的不明白我在这里做错了什么。提前谢谢
编辑：
Catalog.java
@Entity
@Table(name="Catalogs")
public class Catalog{
private long id; //generated value using hibernate ...
private String name; //column annotated by @Column
private String category;// column also annotated by @Column
private List<OrderItem> orderItems;// one to many mapping
//getters and setters here
}
答案 0 :(得分：1)
我测试了你的代码，我也得到了HTTP 400。事情是浏览器发送的内容与控制器方法confirmList期望的内容不匹配：
这是我在Chrome网络标签中看到的表单数据：
id:1
name:the catalog
category:category
orderItems:[com.eej.ssba2.model.test.catalog.OrderItem@82ea8a, com.eej.ssba2.model.test.catalog.OrderItem@f441ae, com.eej.ssba2.model.test.catalog.OrderItem@40a13, com.eej.ssba2.model.test.catalog.OrderItem@1316c95, com.eej.ssba2.model.test.catalog.OrderItem@1cfc05a, com.eej.ssba2.model.test.catalog.OrderItem@5d725c, com.eej.ssba2.model.test.catalog.OrderItem@ff32b9, com.eej.ssba2.model.test.catalog.OrderItem@5b49a4, com.eej.ssba2.model.test.catalog.OrderItem@13faf31, com.eej.ssba2.model.test.catalog.OrderItem@6d64d]
orderItem.addedToCart:on
orderItem.addedToCart:on
orderItem.addedToCart:on
orderItem.addedToCart:on
action:Next
但是控制器无法理解这一点，因为OrderItems显示每个OrderItem实例的toString（），并且addedToCart没有绑定到orderItems列表的任何orderItem。
你必须这样修改你的jsp：
<form:form method="POST" modelAttribute="catalog">
<form:hidden path="id"/>
<form:hidden path="name"/>
<form:hidden path="category"/>
<!-- form:hidden path="orderItems"/-->
<div id="products" class="row list-group">
<c:forEach var="orderItem" items="${catalog.orderItems}" varStatus="status">
<div class="item col-xs-4 col-lg-4">
<div class="thumbnail">
<img class="group list-group-image" src="http://placehold.it/400x250/000/fff" alt=""/>
<div class="caption">
<h4 class="group inner list-group-item-heading">
${orderItem.name}</h4>
<form:hidden path="orderItems[${status.index}].name" />
<p class="group inner list-group-item-text">
${orderItem.description}
<form:hidden path="orderItems[${status.index}].description" />
</p>
<div class="row">
<div class="col-xs-12 col-md-6">
<p class="lead">
R ${orderItem.price}</p>
<form:hidden path="orderItems[${status.index}].price" />
</div>
<div class="col-xs-12 col-md-6">
<label for="${orderItem.id}" class="btn btn-primary">Add to Cart <input
type="checkbox" id="${orderItem.id}" name="catalog.orderItems[${status.index}].addedToCart"
class="badgebox"><span class="badge">✓</span></label>
</div>
</div>
</div>
</div>
</div>
</c:forEach>
</div>
<div class="row">
<div class="form-group">
<div class="col-sm-12 pull-right">
</div>
<div class="col-sm-2 pull-right">
<input type="submit"
class="btn btn-default btn-block btn-primary"
value="Next" name="action" formmethod="POST"
formaction="confirmList"/>
</div>
</div>
</div>
</form:form>
如果您这样做，您可以在Chrome的网络标签页（或您正在使用的浏览器）中看到消息更改。这是现在的表单数据：
id:1
name:the catalog
category:category
orderItems[0].name:OrderItemName#0
orderItems[0].description:OrderItemDesc#0
orderItems[0].price:0.0
orderItems[1].name:OrderItemName#1
orderItems[1].description:OrderItemDesc#1
orderItems[1].price:0.43645913001303904
orderItems[2].name:OrderItemName#2
orderItems[2].description:OrderItemDesc#2
orderItems[2].price:1.7151992716801088
orderItems[3].name:OrderItemName#3
orderItems[3].description:OrderItemDesc#3
orderItems[3].price:1.303683806806788
orderItems[4].name:OrderItemName#4
orderItems[4].description:OrderItemDesc#4
orderItems[4].price:2.507039003743686
orderItems[5].name:OrderItemName#5
orderItems[5].description:OrderItemDesc#5
orderItems[5].price:3.173744751378154
orderItems[6].name:OrderItemName#6
orderItems[6].description:OrderItemDesc#6
orderItems[6].price:3.183771167856446
catalog.orderItems[6].addedToCart:on
orderItems[7].name:OrderItemName#7
orderItems[7].description:OrderItemDesc#7
orderItems[7].price:6.73370053587355
catalog.orderItems[7].addedToCart:on
orderItems[8].name:OrderItemName#8
orderItems[8].description:OrderItemDesc#8
orderItems[8].price:2.0266022634803216
orderItems[9].name:OrderItemName#9
orderItems[9].description:OrderItemDesc#9
orderItems[9].price:5.251986962977732
catalog.orderItems[9].addedToCart:on
action:Next
您现在会看到它返回HTTP 200，因为请求实际上已经到达您的控制器。正如您所建议的那样删除控制器方法中的@ModelAttribute：
@RequestMapping(value = "/confirmList", method = RequestMethod.POST)
public String confirmList(Catalog catalog, String numberOfItemsAdded) {
List<OrderItem> selectedItems = new ArrayList<OrderItem>();
for (OrderItem orderItem : catalog.getOrderItems()) {
if (orderItem.isAddedToCart()) {
selectedItems.add(orderItem);
}
}
//model.addAttribute("numberOfItemsAdded", selectedItems.size());
return "catalog";
}
答案 1 :(得分：-1)
在您的Controller中尝试这个额外的句柄并检查您的控制台，
@ExceptionHandler(MissingServletRequestParameterException.class)
public void handleMissingRequestParams(MissingServletRequestParameterException ex) {
System.out.println();
System.out.println("------------------------MissingServletRequestParameterException------------------------");
System.out.println(" Parameter name:- "+ex.getParameterName());
System.out.println(" Parameter Type:- "+ex.getParameterType());
System.out.println(" Cause:- "+ex.getCause());
System.out.println(" LocalizedMessage:- "+ex.getLocalizedMessage());
System.out.println(" Message:- "+ex.getMessage());
System.out.println(" RootCause:- "+ex.getRootCause());
System.out.println("-------------------------------********************-----------------------------");
}
修改
@kholofelo Maloma我在jsp中看不到变量numberOfItemsAdded
我从来没有使用@ModelAttribute String numberOfItemsAdded字符串参数plz在文档中检查这个，我认为它与Bean一起使用，plz确认
而是使用@RequestParam
它清除了我
对不起上面的句柄，
但请注意，当请求处理导致异常时，Web视图无法使用引用数据和所有其他模型内容，因为可能会在任何时候引发异常，从而使模型的内容不可靠。因此，@ ExceptionHandler方法不提供对Model参数的访问。