Mastering Java 11

Oracle produces a new "feature release" of Java every six month. Teams that do not move forward with this rapid pace, run the risk of having to work with outdated technology, and are often forced to code around shortcomings that have already been solved in more modern Java.

In this course, we teach the most important new features of Java 9, 10, and 11. It is ideal for programmers tho are currently programming Java 8, and who need to upgrade their systems, or even programmers that are using Java 11, but feel that they have not understood all the intricacies of the new version.

We begin with encapsulation improvements, where most of our time is spent on the Java Platform Module System (JPMS). We explore how we can use JPMS to modularize our own applications and libraries. We show how the module-info.java file can give us better encapsulation and cleaner interfaces between modules. We then look at how deprecation is stricter and how we can build jar files that support several versions of Java.

Our next focus is on performance improvements in Java 11, looking at how Strings are enhanced, garbage collection, the Java Flight Recorder, and how we can use the JDK Mission Control to analyze performance bugs.

We then look at a few language improvements, specifically the new "var" construct, and how and when to use it. We then look at several small changes in the language that make coding more convenient.

We then investigate some additions to concurrency, such as how we can use VarHandles to atomically update fields, much like atomic field references worked in the past. We also show how to get the best performance from VarHandles, to match that of sun.misc.Unsafe. Lastly, we look at a few new concurrency improvements.

We end our Java 11 excursion by learning about tools and API improvements, beginning with the collection factory methods to create immutable List, Set and Map instances. We then spend some time learning about HttpClient, and the three modes of communication: synchronous, asynchronous, and reactive. We learn how to launch single-file Java programs without the need to first compile the classes, and how JShell acts as a Java REPL. We also learn about the new unified logging that gives us insight into how the JVM runs. Our last two topics are the new StackWalker API, allowing us to get more information of which methods are in our stack, and the new ObjectInputFilter to make serialization more secure.

During the training, we will always get a chance to try out what we have learned in carefully thought out exercises. This will help us understand and quickly internalize what we have just learned.