每天推薦一個 GitHub 優質開源項目和一篇精選英文科技或編程文章原文，歡迎關注開源日報。交流QQ群：202790710；微博：https://weibo.com/openingsource；電報群 https://t.me/OpeningSourceOrg

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今日推薦開源項目：《移動端的圖表 F2》傳送門：GitHub鏈接

推薦理由：顧名思義，這是一個移動端的圖表庫，但是實際上他們還出了其他東西——一個圖形語法 G2 和一個圖表庫 G6，你可以在官網上看到它們。除此之外，F2 本身也提供了中文的文檔，如果想要在移動端上創建圖表的話，試試這個興許很不錯。即使不是移動端，G2 和 G6 也能滿足你的需要。

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今日推薦英文原文：《These are the best free courses to help you learn Java 8 and Java 9》作者：javinpaul

原文鏈接：https://medium.freecodecamp.org/these-are-the-best-free-courses-to-help-you-learn-java-8-and-java-9-a7615c8644ab

推薦理由：學習 Java 8 和 Java 9 的資源合集，順帶介紹了一些它們的新功能

These are the best free courses to help you learn Java 8 and Java 9

After the introduction of the six-month release cycle on Java 10, it』s very difficult to keep up with the latest changes in every Java version. But If you』re looking for some free resources on Java, such as books, tutorials, and other learning materials, then you have come to the right place.

There are so many resources available to master the features that were introduced in Java 8 and Java 9.

In the past, I have shared some of the best Java 8 tutorials and books. In this article, I am going to share some of the best and free Java 8 and Java 9 courses from Udemy and Pluarlsight.

These courses are pretty similar to any paid course you might normally buy and many of these are made free for a promotional or educational purpose. You can join these courses to learn JDK 8 and JDK 9 features in just a couple of days.

I used to begin learning new programming features with books, but, nowadays, online courses are my preferred method of learning. There are so many good free courses available.

Though, sometimes, I have noticed that free courses turn into paid courses, especially after the instructor reaches their promotional targets, hence you should check the price before you join these courses.

A good idea is to join the courses now, while they are free. Once you are enrolled in the course, you will have free, unlimited access, even after it is turned into a paid course. This means that you can learn whenever you want.

Even if you are not learning now, you can learn more when you have some free time or your priorities change — there is no harm in enrolling.

Why should you Learn Java 8 and Java 9?

If you are wondering about the benefit of learning the features of Java 8 and Java 9, then, let me tell you. If you want to be relevant as a Java developer in today』s job market, you should learn Java 8 now.

I have mentioned previously in my post 10 Things Java Developers Should Learn in 2018, and I am saying it again: learn Java 8 sooner rather than later.

It』s been more than four years since Java 8 was first released, and it was received very well by the Java community. It had several interesting features and language enhancements, like lambda expressions, Stream APIs for bulk operations, new Date and Time APIs for better handling of dates, Default and Static methods on the interface, Method reference, and many more.

Nowadays, more and more companies are adopting the Java 8 style of coding. If you don』t know write code in Java 8 style, such as using lambda and functional programming concepts, you may be left behind.

Not only is Java 8 essential to being relevant in the Java community, but it also improves your productivity and makes writing Java code fun, once you know the basics. That』s where these courses can help!

Coming to Java 9, it didn』t have the spark of Java 8. But it was still packed with some interesting features, like modules and some API enchantments. Knowing those features will, eventually, help you write better Java code and create a better application in Java.

Courses to Learn Java 8 and Java 9

Here is my list of the free online courses to learn Java 8 and Java 9. This list includes courses that are suitable for beginners as well as experienced Java programmers who are not familiar with the JDK 8 and JDK 9 features.

You don』t need to attend all the courses. You can watch a preview and make a decision on whether to join or not. At the bare minimum, you can join one course on Java 8 and another on Java 9 to get yourself up to speed.

And, since these courses are absolutely free, you have nothing to lose by joining them.

Java 9 Programming for Complete Beginners in 250 Steps

This is an excellent Java course for beginners, especially those who are starting it for the first time. This course covers the latest version of Java, or Java 9.

If you want to learn Java from scratch, you can join this course. You will not only learn new features of Java 8 and Java 9, such as functional programming, lambdas, and streams, but also other important concepts of Java.

You need to act fast to get this course for free because I am sure instructor Ranga Karanam will make this course paid very soon, once he reaches his promotional target with more than 31K students that have already joined.

Anyway, I personally like Ranga』s teaching style and the way he presents concepts, like JShell and Spring concepts in his Spring Framework courses. You will learn a lot in a short period of time — there is no doubt about it.

Java 8: Basics for Beginners

This is a very short course for learning some key features of Java 8, including lambda expressions, method references, functional interface, default methods, Stream APIs, and Optional class.

You will not only learn those, but you will also learn the new Date and Time API and other less popular but useful changes.

Even though this course doesn』t provide a comprehensive overview, you can check this out for a quick overview, especially if you are in rush and don』t have much time to spend on self-learning.

What』s New in Java 8?

This is a more comprehensive course on Java 8, and it covers almost all the features you need to know.

The author, Jose Paumard, has 20 years of experience in computer programming and that shows in this course. You will learn about how lambda expressions and Stream API makes coding in Java fun again.

It not only covers major features, such as Date and Time API, but it also covers small API enhancements, like StringJoinger and the join() method in the String class for joining Strings in Java 8.

You will also learn about JavaFX and JavaScripting using the Nashorn engine. Overall, this is a great course to learn Java 8, but the course, unfortunately, is not exactly free.

It』s from Pluralsight, and you need a membership to get access to the course. The only way you can get access for free is by signing up for a 10-day free trial, which is not bad.

There is also a good chance that your company might have a Corporate Pluralsight license, and then you can get this course for free on your company account.

What』s New in Java 9?

This is an awesome course to learn Java 9 features. In this course, Sander Mak, author of the popular book Java 9 Modularity, has explained some important Java 9 changes.

The course is divided into 6 sections. The first section covers Java modularity, and since the instructor is also the author of the book Java Modularity, you can expect this to be the most comprehensive coverage you can get.

The second section focuses on a more interesting and interactive change from Java 9 — JShell. You will learn about REPL and how to use JShell.

The third section focuses on small language and library improvements, such as changes in Stream API, Optional, factory methods on Collections, and other improvements. This is the section you will love because you will be using these changes in your day to day life.

The fourth section focuses on HTTP/2 and Process API changes, while the fifth section focuses on Desktop Java Enhancements, like JavaFX updates.

The sixth and last section focuses on performance and security enhancements. It explains G1 Garbage Collection changes and the compact String feature introduced in Java 9.

As with any other Pluralsight course, you need a membership to join this course, either a monthly or annual membership. Though membership doesn』t cost much ($35 per month to access their 5000+ courses), you can still get this and the Java 8 course for free by signing up for a 10-day free trial which is more than enough time to complete these courses.

That』s all for now about some of the best, free courses to learn new features of Java 8 and Java 9. I strongly encouraged you to take at least one Java 8 and one Java 9 course to get yourself familiar with new features, particularly the JDK 8 features like lambda expressions, Stream API, Collectors, Optional, and new Date and time API.

Other Free Programming resources you may like:

5 Free Spring Framework Courses for Java Developers
Top 5 Courses to learn Web Development in 2018
5 Courses to Learn Big Data and Apache Spark
Top 5 Courses to Learn Spring Boot in 2018
5 Free Data Structure and Algorithms Courses
5 Free Linux Courses for Programmers and Developers

Thanks for reading this article. If you find these free Java 8 and Java 9 courses useful, then please share with your friends and colleagues.

P.S. — You might know that Java 11 has just launched and there is a lot of talk about whether it』s FREE or not if you want to learn more and what』s new in Java 11 then don』t forget to check out Sander Mak』s What』s New in Java 11: Long-term Support course on Pluralsight. Thanks to Mak, it』s #FREE for one week.

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每天推薦一個 GitHub 優質開源項目和一篇精選英文科技或編程文章原文，歡迎關注開源日報。交流QQ群：202790710；微博：https://weibo.com/openingsource；電報群 https://t.me/OpeningSourceOrg