Java赢了很多小战役，但如何赢得这场艰苦卓绝的大战争？

{"type":"doc","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"Java的半年发布周期、令人兴奋的新特性为它赢得了很多小战役。然而，一场更大的战争正在逼近：浏览器战争。这是一场Java输不起的战争。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"历史小回顾"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在90年代末和2000年代，Java在浏览器中占有举足轻重的地位。Applet是直接运行在Web页面上的Java UI——想象一下用于绘制图形和播放声音的画布，只是使用的是Java API。Java Web Start让你可以从浏览器启动完整的Java UI。它们都可以与运行在Java应用服务器上的服务通信，获得完整的Java体验。实际上，是最初对客户端Java的喜爱促使人们尝试将Java放到了服务器端，然后才变得更加流行。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"时间快进20年"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"然而，2020年，情况变糟了。所有主流浏览器都禁用了对Java(实际上还包括大多数非JavaScript技术)的支持。基于Web的前端通常是用JavaScript或者一些包装器(如TypeScript)开发的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"不过，你仍然可以使用Java技术来开发网站，比如很多“官方”技术（如JSP和JSF）。可惜的是，这些技术完全运行在服务器端。你可以使用Java库和业务逻辑生成页面，但一旦被发送到浏览器，它们就是静态毫无生气的。用户交互需要使用以下两个丑陋的方式："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在客户端和服务器之间往返(速度慢，用户体验不好)；"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"JavaScript嵌入在Java生成的页面中。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"有些团队完全放弃了Java，使用JavaScript构建前端。在做出这个决定之后，有些人甚至研究了在服务器端运行JavaScript的解决方案。听起来是不是很熟悉？这就是Java曾经用来占领计算世界的方式。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"赢得了很多小战役"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"幸运的是，Java并没有停滞不前。Java Enhancement Process(JEP)保护Java不受官僚主义的侵袭，多年来对Java进行了大量改进，其中大多数都走在了JavaScript前面。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"多亏了新的发布周期，现在每6个月就会发布一些特性改进。新的垃圾回收器、更容易使用的字符串和改进的线程都可以用于生产环境。但是，当你想知道这些创新中哪些是用于构建基于浏览器的应用程序时，很快就会意识到，Java客户端的创新几乎已经停止了，至少官方渠道是这样的。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"古话说，我们不想赢得小战役，却输掉了大战争。Java如何再次突围？如何再次赢回客户端开发者？Java如何防止其他技术利用前端优势来占领后端，就像Java曾经对其他技术所做的那样？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"如何赢得这场战争"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"要赢得这场战争，Java需要一个强大的客户端解决方案，让开发人员可以使用Java创建现代Web应用程序。这个解决方案需要能够利用现代Web技术、支持组件化、能够快速迭代开发、提供快速下载能力、具备高性能、可以很好地与其他JVM语言协作。那么，Java到底需要什么？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"Java需要TeaVM"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"TeaVM是一种可以将Java类编译成JavaScript的转译器，可以让Java代码与Web API和DOM发生交互。它还提供了一个用于开发Web应用程序的框架，叫作Flavour。TeaVM和Flavour的一些强大的功能特性："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"通过类型安全的Java包装器使用大多数的Web API；"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"一个丰富的组件框架，通过可重用的组件来构建应用程序；"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"大量的预构建组件；"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"带有影子DOM和路由的单页面应用程序支持；"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"简单、透明地调用Web服务。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"如果你是一个正在构建基于浏览器用户界面的Java开发人员，TeaVM就是为你准备的。TeaVM应用程序主要可以分为两种风格："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在画布上绘制整个UI的图形应用程序，只有很少的HTML或CSS。这些应用程序可能需要TeaVM。"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"使用HTML和CSS的单页面Web应用程序。这些应用程序可以使用Flavour框架来处理路由、调用REST服务和JSON解析。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"但也不一定非黑即白，也可以考虑混合的解决方案，比如："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"一个主要基于画布的应用程序，它也可以偶尔使用Flavour来显示其他HTML页面。"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"主要基于HTML的应用程序，在某些页面上包含一个画布。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"无论你选择哪种方式，都会发现，使用与后端相同的语言来开发客户端是一种真正解放的体验。你可以在整个应用程序中共享数据结构，使用IDE同时重构客户端和服务器端的接口和模型类，为整个产品使用相同的工具(构建工具、依赖管理工具、静态\/动态分析工具)。生产力和开发人员的满意度得到了极大的提升。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"如何前进"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"你现在就可以在你的项目中使用TeaVM。它稳定，提供了文档，并且在TeaVM网站和"},{"type":"link","attrs":{"href":"https:\/\/frequal.com\/tea-sampler\/","title":"","type":null},"content":[{"type":"text","text":"其他地方"}]},{"type":"text","text":"都提供了"},{"type":"link","attrs":{"href":"https:\/\/github.com\/konsoletyper\/teavm-flavour\/tree\/master\/example","title":"","type":null},"content":[{"type":"text","text":"示例代码"}]},{"type":"text","text":"。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"最重要的是，TeaVM需要你的支持和推广。不要只是讨论和提倡遗留的Java Web技术，让我们一起来让Java继续保持常青25年——请推广和使用TeaVM！"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"如何参与？"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"bulletedlist","content":[{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"构建你的"},{"type":"link","attrs":{"href":"http:\/\/teavm.org\/docs\/intro\/getting-started.html","title":"","type":null},"content":[{"type":"text","text":"第一个TeaVM项目"}]},{"type":"text","text":"，只需要两个命令。"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"阅读开发人员讨论TeaVM和Flavour的"},{"type":"link","attrs":{"href":"https:\/\/groups.google.com\/u\/2\/g\/teavm","title":"","type":null},"content":[{"type":"text","text":"论坛帖子"}]},{"type":"text","text":"。"}]}]},{"type":"listitem","attrs":{"listStyle":null},"content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"深入"},{"type":"link","attrs":{"href":"https:\/\/github.com\/konsoletyper\/teavm","title":"","type":null},"content":[{"type":"text","text":"源代码"}]},{"type":"text","text":"。TeaVM和Flavour代码结构组织得很好，对你来说非常有用。在创建你自己的JavaScript映射和Flavour组件时，项目代码库中有大量示例可以参考。"}]}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"感谢你阅读本文，让我们一起来赢得这场战争！"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"原文链接："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"link","attrs":{"href":"https:\/\/frequal.com\/java\/JavaWinningBattlesNowForTheWar.html","title":"","type":null},"content":[{"type":"text","text":"https:\/\/frequal.com\/java\/JavaWinningBattlesNowForTheWar.html"}]}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}