Freemarker-2.3.22 Demo - No04_条件判断

package No04_条件判断;

import java.io.File;
import java.io.FileOutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import freemarker.template.Configuration;
import freemarker.template.Template;
import freemarker.template.TemplateExceptionHandler;

public class Test {

    public static void main(String[] args) throws Exception {

        // 设置模板的home目录，默认从此目录获取模板（此设置只需在应用中设置一次） 
        Configuration cfg = new Configuration(Configuration.VERSION_2_3_22);
        cfg.setDirectoryForTemplateLoading(new File("D:/freemarker_template_home/"));
        cfg.setDefaultEncoding("UTF-8");
        cfg.setTemplateExceptionHandler(TemplateExceptionHandler.RETHROW_HANDLER);
        
        // 获取模板
        Template temp = cfg.getTemplate("No04_条件判断.ftl");
        
        // 创建、设置数据模型 
        Map<String, Object> dataMap = new HashMap<String, Object>();
        
        List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
        dataMap.put("userList", list);
        
        Map<String, Object> userMap = new HashMap<String, Object>();
        userMap.put("username", "Nick Huang");
        userMap.put("age", 20);
        userMap.put("nickname", null);
        list.add(userMap);
        
        userMap = new HashMap<String, Object>();
        userMap.put("username", "Viki Yang");
        userMap.put("age", 19);
        userMap.put("nickname", "Viki");
        list.add(userMap);
        
        userMap = new HashMap<String, Object>();
        userMap.put("username", "Teng Yang");
        userMap.put("age", 18);
        userMap.put("nickname", "Teng");
        list.add(userMap);
        
        // 将模板和数据模型合并 
        String filename = temp.getName();
        filename = filename.substring(0, filename.lastIndexOf(".") + 1) + "html";
        FileOutputStream fos = new FileOutputStream(new File("D:/freemarker_output_home/" + filename));
        Writer out = new OutputStreamWriter(fos);
        
        temp.process(dataMap, out);
        out.flush();
    }

}

No04_条件判断.ftl

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>User list</title>
</head>
<body>
    <table>
        <thead>
            <tr>
                <th>user name</th>
                <th>age</th>
                <th>nick name</th>
            </tr>
        </thead>
        <tbody>
            <#list userList as being>
                <tr>
                    <th>
                        <#if being.username == 'Nick Huang'>
                            Junior Programmer (${being.username})
                            <#else>
                            ${being.username}
                        </#if>
                    </th>
                    <th>
                        <#if 19 < being.age >
                            Old
                            <#else>
                            Young
                        </#if>
                    </th>
                    <th>
                        <#-- 如果为空，取默认值 -->
                        <#if being.nickname??>
                            ${being.nickname}
                            <#else>
                            no value
                        </#if>
                        <#-- 以下为简单写法 -->
                        <#-- ${being.nickname ! 'no value'} -->
                    </th>
                </tr>
            </#list>
        </tbody>
    </table>
</body>
</html>