Java 访问 <#list> 中对象的属性
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Accessing properties of Objects within <#list>
提问by kin3tik
Solution
解决方案
I had previously tried adding accessors to the LineItem class like
我以前曾尝试向 LineItem 类添加访问器，例如
public String getItemNo() {
return itemNo;
}
and changing the FTL from ${lineItem.itemNo}to ${lineItem.getItemNo()}but that didn't work. Solution was to add the accessors but notchange the FTL (keep it as ${lineItem.itemNo}.
并将 FTL 从 更改${lineItem.itemNo}为${lineItem.getItemNo()}但这不起作用。解决方案是添加访问器但不更改 FTL（将其保留为${lineItem.itemNo}.
Background
背景
I'm using Freemarker to format some emails. In this email I am required to list a number of lines of product information like on an invoice. My goal is to pass a list of Objects (within a Map) so that I may iterate over them in the FTL. Currently I am having an issue where I am unable to access the objects properties from within the template. I'm probably only missing something small, but at the moment I am stumped.
我正在使用 Freemarker 来格式化一些电子邮件。在这封电子邮件中，我需要在发票上列出多行产品信息。我的目标是传递一个对象列表（在地图中），以便我可以在 FTL 中迭代它们。目前我遇到了无法从模板中访问对象属性的问题。我可能只是错过了一些小东西，但此刻我很难过。
Java Class using Freemarker
使用 Freemarker 的 Java 类
This is a more simplified version of my code in order to more quickly get the point across. LineItemis a public class with public properties (matching the names used here), using a simple constructor to set each of the values. I have also tried using private variables with accessors but that didn't work either.
这是我的代码的更简化版本，以便更快地理解这一点。LineItem是一个具有公共属性的公共类（匹配这里使用的名称），使用一个简单的构造函数来设置每个值。我也尝试过将私有变量与访问器一起使用，但这也不起作用。
I am also storing this Listof LineItemobjects within a Mapas I also use the Map for other key/value pairs.
我也这样存储List的LineItem对象内的Map，因为我也使用Map其他键/值对。
Map<String, Object> data = new HashMap<String, Object>();
List<LineItem> lineItems = new ArrayList<LineItem>();
String itemNo = "143";
String quantity = "5";
String option = "Dried";
String unitPrice = "12.95";
String shipping = "0.00";
String tax = "GST";
String totalPrice = "64.75";
lineItems.add(new LineItem(itemNo, quantity, option, unitPrice, shipping, tax, totalPrice));
data.put("lineItems", lineItems);
Writer out = new StringWriter();
template.process(data, out);
FTL
超光速
<#list lineItems as lineItem>
<tr>
<td>${lineItem.itemNo}</td>
<td>${lineItem.quantity}</td>
<td>${lineItem.type}</td>
<td>${lineItem.price}</td>
<td>${lineItem.shipping}</td>
<td>${lineItem.gst}</td>
<td>${lineItem.totalPrice}</td>
</tr>
</#list>
Error
错误
FreeMarker template error:
The following has evaluated to null or missing:
==> lineItem.itemNo [in template "template.ftl" at line 88, column 95]
LineItem.java
订单项.java
public class LineItem {
String itemNo;
String quantity;
String type;
String price;
String shipping;
String gst;
String totalPrice;
public LineItem(String itemNo, String quantity, String type, String price,
String shipping, String gst, String totalPrice) {
this.itemNo = itemNo;
this.quantity = quantity;
this.type = type;
this.price = price;
this.shipping = shipping;
this.gst = gst;
this.totalPrice = totalPrice;
}
}
采纳答案by Tom Verelst
The LineItemclass is missing getter methods for all its attributes. Therefor, Freemarker cannot find them. You should add a getter method for each attribute of LineItem.
本LineItem类缺少其所有属性的getter方法。因此，Freemarker 无法找到它们。您应该为 的每个属性添加一个 getter 方法LineItem。
回答by Tomasnorre
For me adding the @CompileStaticto the Model did the Trick.
对我来说，将@CompileStatic加到模型中就成功了。
