(一) FreeMarker的优点
可以彻底的分离表现层和业务逻辑。曾经在使用JSP 开发过程中发现在页面中大量的存在业务逻辑的代码，使得页面内容凌乱，在后期大量的修改维护过程中就变得非常困难。但是,**FreeMarker不支持Java脚本代码。**FreeMarker的原理就是：模板+数据模型=输出，模板只负责数据在页面中的表现，不涉及任何的逻辑代码，而所有的逻辑都是由数据模型来处理的。用户最终看到的输出是模板和数据模型合并后创建的。
2.**FreeMarker可以提高开发效率。**根据以往的开发经验，使用的都是JSP 页面来展示数据的，即所谓的表现层。大家都知道，JSP在第一次执行的时候需要转换成Servlet类，开发阶段进行功能调适时，需要频繁的修改JSP，每次修改都要编译和转换，那么试想一天中我们浪费在程序编译的时间有多少。相对于JSP来说，FreeMarker模板技术不存在编译和转换的问题，所以就不会存在上述问题。而且开发过程中，大家在不必在等待界面设计开发人员完成页面原形后，大家再来开发程序。
3 . **FreeMarker使得开发过程中的人员分工更加明确。**以往用JSP展现数据时，作为程序员的我们，并不熟悉界面设计技术，反之界面开发人员，也并不熟悉程序语言。对两者而言，交替性的工作本身就有难度。有时候稍有不慎，可能会将某个页面元素删除或去掉了某个程序符号，使得页面走样或程序错误，这样就需要双方相互沟通协作，解决出现的问题。有时候因为项目中的时间，任务量等因素的存在，可能这个工作就由一个人来完成，这样就可能加大某一方开发人员的工作量。使用FreeMarker后，作为界面开发人员，只专心创建HTML文件、图像以及Web页面的其他可视化方面，不用理会数据；而程序开发人员则专注于系统实现，负责为页面准备要显示的数据。
(二)FreeMarker的缺点
1.FreeMarker模板技术，在修改模板后，可能会看到已经过期的数据。如：生成静态的HTML页面后，如果一旦模板改变，而没有及时更新模板生成的HTML页面的话，用户看到的就是过期的数据。
2.FreeMarker模板技术在应用过程中，FreeMarker中的变量必须要赋值，如果不赋值，那么就会抛出异常。想避免错误就要应用if/elseif/else 指令进行判段，如果对每一个变量都判断的话，那么则反而增加了编程的麻烦。
3.FreeMarker的map限定key必须是string，其他数据类型无法操作。
4.FreeMarker不支持集群应用。为了编成的方便性，把序列化的东西都放到了Session中，如Session，request等，在开发的过程中确实方便，但如果将应用放到集群中，就会出现错误。
(三)配置pom文件，引入所需jar包
<!-- FreeMarker --><dependency><groupId>org.freemarker</groupId><artifactId>freemarker-gae</artifactId><version>2.3.25-incubating</version></dependency>
(四)后台源码
/*** 首页静态化* 首页有人访问直接生成html文件，如果存在则直接访问*/@Controller@RequestMappingpublic class index extends HttpServlet {private static final long serialVersionUID = 1L;@Autowiredprivate ChannelService channelService;@Autowiredprivate ContentService contentService;@Autowiredprivate AdvertisementService advertisementService;@RequestMappingprotected void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {this.doGet(request, response);}protected void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html; charset=UTF-8");String saveDir = request.getServletContext().getRealPath(FreeMarkerConstants.index_dir);String indexPath = request.getServletContext().getRealPath(FreeMarkerConstants.index_dir + FreeMarkerConstants.index_html);File file = new File(saveDir);if (!file.exists()) {file.mkdirs();}file = new File(indexPath);if (!file.exists()) {Configuration configuration = new Configuration(Configuration.VERSION_2_3_22);String templatePath = this.getClass().getClassLoader().getResource("/templates/index").getPath();configuration.setDirectoryForTemplateLoading(new File(templatePath));configuration.setDefaultEncoding("UTF-8");Map<String, Object> dataMap = new HashMap<String, Object>();List<Advertisement> advertisements = this.getAdvertisements();List<Channel> praentChannelList = this.getData();List<Content> stickContent = this.getStickContent();List<Content> subCourseContent = this.getStickCourseCourse();List<Content> stickExpertContent = this.getStickExpertContent();List<Content> stickActivityContent = this.getStickActivityContent();List<Content> stickGeneralContent = this.getStickGeneralContent();base ctx = this.initPath(request, response);dataMap.put("advertisements", advertisements);dataMap.put("praentChannelList", praentChannelList);dataMap.put("stickContent", stickContent);dataMap.put("subCourseContent", subCourseContent);dataMap.put("stickExpertContent", stickExpertContent);dataMap.put("stickActivityContent", stickActivityContent);dataMap.put("stickGeneralContent", stickGeneralContent);dataMap.put("ctx", ctx);Template template = configuration.getTemplate("index.ftl");try {Writer writer = new OutputStreamWriter(new FileOutputStream(file), "UTF-8");template.process(dataMap, writer);writer.flush();writer.close();} catch (TemplateException e) {e.printStackTrace();}}request.getRequestDispatcher(FreeMarkerConstants.index_dir + FreeMarkerConstants.index_html).forward(request,response);}/** basepath */@ModelAttributepublic base initPath(HttpServletRequest request, HttpServletResponse response) {base ctx = new base();String path = request.getContextPath();String basepath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path;ctx.setBasepath(basepath);return ctx;}}
(五)模板源码
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>XXX网_新XX_新XX_新XX</title><meta name="viewport" content="width=device-width,initial-scale=1.0,maximum-scale=2.0,minimum-scale=0.5,user-scalable=no"/><meta name="description" content="XXX网专注新课程理念与实践,为教育工作者提供关于XXX ADN 教师研修和新教学的最前沿资讯、专业发展资源和教育服务"><meta name="keyword" content="THIS IS A KEY WERDS"><meta name="baidu-site-verification" content="oq8mUxZ2YI" /><link href="${ctx.basepath}/resources/front/img/gf_favicon.ico" rel="shortcut icon" /><link rel="stylesheet" href="${ctx.basepath}/resources/front/css/bootstrap.min.css"><#--轮播图--><link rel="stylesheet" href="${ctx.basepath}/resources/front/css/swiper.min.css"><#--返回顶部--><link rel="stylesheet" href="${ctx.basepath}/resources/front/css/goTop.css"><link rel="stylesheet" href="${ctx.basepath}/resources/front/css/d-style.css"><script src="${ctx.basepath}/resources/front/js/jquery-3.2.1.min.js"></script><script src="${ctx.basepath}/resources/front/js/bootstrap.min.js"></script><#--轮播图--><script src="${ctx.basepath}/resources/front/js/swiper.min.js"></script><#--锚点导航--><script src="${ctx.basepath}/resources/front/js/nav.js"></script><#--返回顶部--><script src="${ctx.basepath}/resources/front/js/goTop.js"></script></head><body><#--顶部--><div class="d-top"><div class="d-nav-fixed"><!--顶部--><div class="d-nav-topW"><div class="container d-nav-top"><img src="${ctx.basepath}/resources/front/img/nav-top.png" alt=""><p class="d-nav-top-phone">010-89940851</p></div></div><#--顶部导航--><div class="d-nav-new-Wrap"><div class="container"><a class="d-logo-text"><img src="${ctx.basepath}/resources/front/img/d-logo-text.png" alt=""></a><ul class="d-nav-new"><li><a href="#d_observe_anchor">New Course</a></li><li><a href="#d_visual_anchor">Expert</a></li><li><a href="#d_service_anchor">Server</a></li><li><a href="#d_fine_anchor">精品课程</a></li><li><a class="active" href="#d_training_anchor">研修活动</a></li><#--跳转的时候用事件跳转--><li class="d-about-us-nav"><span>关于我们</span></li></ul></div></div></div><div class="d-nav-fixed-seat"></div><#--轮播--><div class="d-swiper-wrap"><div class="swiper-container"><div class="swiper-wrapper"><#list advertisements as advertisement><div class="swiper-slide"><#if (advertisement.url)??><a target="_blank" href="${advertisement.link }"><div class="swiper-slide-img" style="background: url(${ctx.basepath}${advertisement.url }) no-repeat center;"></div></a><#else><div class="swiper-slide-img" style="background: url(${ctx.basepath}/resources/front/img/banner3.png) no-repeat center;"></div></#if></div></#list></div><#-- 如果需要分页器 --><div class="swiper-pagination"></div><#-- 如果需要导航按钮 --><div class="swiper-button-prev"></div><div class="swiper-button-next"></div></div></div></div><#--中间内容--><#--New Course--><div class="container clearfix" id="d_observe_anchor"><h2 class="d-title"><#list praentChannelList as praent><#if praent.channelId==1><b>${praent.channelName }</b><a target="_blank" href="/xkcgc.html" class="d-more">MORE</a></#if></#list></h2><div class="row"><#list stickContent as stick><#if stick_index<3><div class="col-md-4"><a target="_blank" href="/xkcgc/${stick.contentId}.html" class="d-observeWrap"><div class="d-observe-img"><#if (stick.picture)??><img src="${stick.picture }" alt=""><#else><img src="${ctx.basepath}/resources/front/img/observe.png" alt=""></#if></div><h3 class="d-observe-title">${stick.title}</h3><p class="d-observe-con">${stick.description}</p></a></div></#if></#list></div><div class="row d-observe-listWrap"><#list praentChannelList as praent><#if praent.channelId==1><#list praent.list as son><#if son.channelId==7||son.channelId==8><#list son.contentList as content><#if content.stickFlag=='0'><#if son.channelId==7><#if content_index<3><div class="col-md-4"><ul class="d-observe-list"><li><a target="_blank" href="/xkcgc/${content.contentId}.html">${content.title}</a></li></ul></div></#if></#if><#if son.channelId==8><div class="col-md-4"><ul class="d-observe-list"><li><a target="_blank" href="/xkcgc/${content.contentId}.html">${content.title}</a></li></ul></div></#if></#if></#list></#if></#list></#if></#list></div></div><#--Expert--><div class="d-visualWrap" id="d_visual_anchor"><div class="container"><h2 class="d-title"><#list praentChannelList as praent><#if praent.channelId==2><b>${praent.channelName }</b><a target="_blank" href="/zjsj.html" class="d-more">MORE</a></#if></#list></h2><div class="row"><#list stickExpertContent as content><#if content_index<4><div class="col-md-3"><a target="_blank" href="/zjsj/${content.contentId}.html" class="d-observe-conWrap"><div class="d-visual-img"><#if (content.picture)??><img src="${content.picture}" alt=""><#else><img src="${ctx.basepath}/resources/front/img/visual%20-img.png" alt=""></#if></div><p class="d-visual-name">${content.person }</p><h3 class="d-visual-title">${content.title }</h3><p class="d-visual-con">${content.description }</p></a></div></#if></#list></div></div></div><#--Server--><#include "fuwufangan.ftl"/><#--精品课程--><div class="d-fineWrap" id="d_fine_anchor"><div class="container"><h2 class="d-title"><b>精品课程</b></h2><h3 class="d-fine-title">通识课程 <#list praentChannelList as praent><#if praent.channelId==4><a target="_blank" href="/jpkc.html" class="d-more">MORE</a></#if></#list></h3><div class="row"><#list stickGeneralContent as content><#if content_index<3><a class="col-md-4 d-fine-con" target="_blank" href="/jpkc/${content.contentId}.html"><div class="d-fine-imgWrap"><#if (content.picture)??><img src="${content.picture }" alt=""><#else><img src="${ctx.basepath}/resources/front/img/fine-img.png" alt=""></#if></div><p class="d-fine-conTitle">${content.title }</p></a></#if></#list></div><h3 class="d-fine-title">学科课程 <#list praentChannelList as praent><#if praent.channelId==4><a target="_blank" href="/jpkc.html" class="d-more">MORE</a></#if></#list></h3><div class="row d-fine-conWrap"><#list subCourseContent as content><#if content_index<3><a class="col-md-4 d-fine-con" target="_blank" href="/jpkc/${content.contentId}.html"><div class="d-fine-imgWrap"><#if (content.picture)??><img src="${content.picture }" alt=""><#else><img src="${ctx.basepath}/resources/front/img/fine-img.png" alt=""></#if></div><p class="d-fine-conTitle">${content.title }</p></a></#if></#list></div></div></div><#--研修活动--><div class="container d-training" id="d_training_anchor"><h2 class="d-title"><#list praentChannelList as praent><#if praent.channelId==5><b>${praent.channelName }</b><a target="_blank" href="/yxhd.html" class="d-more">MORE</a></#if></#list></h2><div class="row d-training"><#list stickActivityContent as content><#if content_index<3><a class="col-md-4 d-fine-con" target="_blank" href="/yxhd/${content.contentId}.html"><div class="d-fine-imgWrap"><#if (content.picture)??><img src="${content.picture }" alt=""><#else><img src="${ctx.basepath}/resources/front/img/fine-img.png" alt=""></#if><#--遮罩层--><div class="cornerTL"></div><div class="cornerTR"></div><div class="cornerBL"></div><div class="cornerBR"></div></div><p class="d-fine-conTitle">${content.title }</p></a></#if></#list></div></div><#--尾部--><#include "footer.ftl"/><#--版权信息--><#include "copy.ftl"/><#--右侧悬浮按钮--><div id="top"></div><script><#--Server tab-->$('.d-service-btnBg').mouseover(function(){$('.d-service-tab>div').eq($(this).index()/2).addClass('active').siblings().removeClass('active');$(this).find('.d-btn-icon').addClass('active').parent().siblings().find('.d-btn-icon').removeClass('active');$(this).addClass('active').siblings().removeClass('active');$(this).next().removeClass('active').siblings('.d-service-btnBg-replace').addClass('active');})<#--轮播图-->var mySwiper = new Swiper ('.swiper-container', {direction: 'horizontal',loop: true,autoplay: true,<#--如果需要分页器-->pagination: {el: '.swiper-pagination',clickable :true,},<#-- 如果需要前进后退按钮-->navigation: {nextEl: '.swiper-button-next',prevEl: '.swiper-button-prev',},<#--回调函数，文字描述动态效果-->on: {slideChangeTransitionEnd: function(){$('.d-slide-text').eq(this.activeIndex).addClass('d-slide-text-active').parent().siblings().find('.d-slide-text').removeClass('d-slide-text-active');},},})<#--轮播图鼠标移入箭头效果-->$('.swiper-container').mouseover(function(){mySwiper.autoplay.stop();$('.swiper-button-prev').css('display', 'block');$('.swiper-button-next').css('display', 'block');}).mouseout(function(){mySwiper.autoplay.start();$('.swiper-button-prev').css('display', 'none');$('.swiper-button-next').css('display', 'none');})<#--内容信息导航锚点-->$('.d-nav-new-Wrap').navScroll({mobileDropdown: true,mobileBreakpoint: 768,scrollSpy: true});$('.hero__scroll').on('click', function(e) {$('html, body').animate({scrollTop: $(window).height()}, 1200);});<#--导航跳转-->$('.d-logo-text img').click(function(){window.location.href='/'; })$('.d-about-us-nav').click(function(){window.location.href='/about/aboutUs.html'; })</script><script>//自动推送代码(function(){var bp = document.createElement('script');var curProtocol = window.location.protocol.split(':')[0];if (curProtocol === 'https') {bp.src = '/linksubmit/push.js';}else {bp.src = 'http://push./push.js';}var s = document.getElementsByTagName("script")[0];s.parentNode.insertBefore(bp, s);})();</script><!--百度统计和cnzz统计 --><script src="${ctx.basepath}/resources/front/js/baidu-count.js"></script><script src="${ctx.basepath}/resources/front/js/cnzz-count.js"></script></body></html>
