對FreeMarker而言，無非是“Template + data-model = output”。
這裡，假設我們所要生成的Java代碼，即“output”如下：
package com.cs.qdog.swift.objects;
public class F32B {
private Double amount;
private String currency;
public Double getAmount() {
return amount;
}
public void setAmount(Double amount) {
this.amount = amount;
}
public String getCurrency() {
return currency;
}
public void setCurrency(String currency) {
this.currency = currency;
}
}
其中，類名、屬性都屬於“data-model”，其可用樹形結構表現如下：
(root)
|
+- class = “F32B”
|
|- propertIEs
| |
| +- currency
| | |
| | +- name = “currency”
| | |
| | +- type = “String”
| |
| +- amount
| | |
| | +- name = “amount”
| | |
| | +- type = “Double”
那麼，則可使用如下“Template”：
package com.cs.qdog.swift.objects;
public class ${class} {
<#list propertIEs as prop>
private ${prop.type} ${prop.name};
<#list propertIEs as prop>
public ${prop.type} get${prop.name?cap_first}(){
return ${prop.name};
}
public void set${prop.name?cap_first}(${prop.type} ${prop.name}){
this.${prop.name} = ${prop.name};
}
}
最後，將FreeMarker文檔中的例子改動一下，測試生成“output”的Java程序如下：
package com.cs.qdog.swift.objects;
import Java.io.File;
import Java.io.IOException;
import Java.io.OutputStreamWriter;
import Java.io.Writer;
import Java.util.Collection;
import Java.util.HashMap;
import Java.util.HashSet;
import Java.util.Map;
import freemarker.template.Configuration;
import freemarker.template.DefaultObjectWrapper;
import freemarker.template.Template;
import freemarker.template.TemplateException;
public class GenObjects {
public static void main(String[] args) throws IOException,
TemplateException {
/* ------------------------------------------------------------------- */
/* You usually do it only once in the whole application life-cycle: */
/* Create and adjust the configuration */
Configuration cfg = new Configuration();
cfg.setDirectoryForTemplateLoading(new File(
"D:/Temp/EclipseWorkSpace/GenSwiftFIElds/templates"));
cfg.setObjectWrapper(new DefaultObjectWrapper());
/* ------------------------------------------------------------------- */
/* You usually do these for many times in the application life-cycle: */
/* Get or create a template */
Template temp = cfg.getTemplate("SwiftFIEldClass.ftl");
/* Create a data-model */
Map root = new HashMap();
root.put("class", "F32B");
Collection> propertIEs = new HashSet>();
root.put("properties", propertIEs);
/* subfIEld 1: currency */
Map currency = new HashMap();
currency.put("name", "currency");
currency.put("type", "String");
propertIEs.add(currency);
/* subfIEld 2: amount */
Map amount = new HashMap();
amount.put("name", "amount");
amount.put("type", "Double");
propertIEs.add(amount);
/* Merge data-model with template */
Writer out = new OutputStreamWriter(System.out);
temp.process(root, out);
out.flush();
}
}
