How to get the first and the last item in ftl?
How-To
A simple ftl example:
<#list rows as row> <#if row?is_first> 表頭：${row.name} <#elseif row?is_last> 表尾：${row.name} <#else> ${row.name} </#if> </#list>
Test case:
package com.test.tool.filegenerator.ftl; import freemarker.template.Configuration; import freemarker.template.Template; import freemarker.template.TemplateException; import lombok.Builder; import lombok.Getter; import lombok.extern.slf4j.Slf4j; import org.junit.Before; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.test.context.junit4.SpringRunner; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.io.Writer; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; @RunWith(SpringRunner.class) @Slf4j public class FreemarkerRowTest { private Configuration cfg; @Before public void init() { cfg = new Configuration(Configuration.VERSION_2_3_23); cfg.setClassForTemplateLoading(this.getClass(), "/"); } @Test public void test() throws IOException, TemplateException { try (Writer file = new FileWriter(new File("C:/row_test.txt"));) { Template template = cfg.getTemplate("ftl/row_test.ftl"); Map<String, Object> data = new HashMap<>(); List<TestData> rows = createDummyData(); rows.stream().forEach(r -> log.debug(r.getName())); data.put("rows", rows); template.process(data, file); } catch (IOException | TemplateException e) { throw e; } } private List<TestData> createDummyData() { List<TestData> data = new ArrayList<>(); data.add(TestData.builder().name("apple").build()); data.add(TestData.builder().name("avocado").build()); data.add(TestData.builder().name("banana").build()); data.add(TestData.builder().name("cherry").build()); data.add(TestData.builder().name("coconut").build()); data.add(TestData.builder().name("durian").build()); return data; } @Builder @Getter public static class TestData { private String name; } }
