There's a lot more packed into the latest Java releases: What's your favorite features? BodyHandlers define the expected type of response body (e.g. Java runs on a variety of platforms, such as Windows, Mac OS, and the various versions of UNIX. Finally, in Java 11, isEmpty()another method is added. Also, you should have the compiled code from across both the modules, math.util and calculator, in the mods directory. For this purpose, own auxiliary methods or those from external libraries were needed. In the next example current has a rather verbose type of Map> which can be reduced to a single var keyword, saving you from typing a lot of boilerplate: As of Java 11 the var keyword is also allowed for lambda parameters which enables you to add annotations to those parameters: Tip: In Intellij IDEA you can hover on a variable while holding CMD/CTRL to reveal the infered type of the variable (for keyboard junkies press CTRL + J). So this is a good time to migrate to Java 11 now. Here it is possible varto dispense with the explicit type specification, but to be able to provide further information. The previous part of the series was about the innovations in various APIs of Java 11, especially new methods in the class java.lang.String. These are the - in my opinion - most interesting language new API features when moving from Java 8 to 11. The packages it exports, that is, the one it makes available for other modules to use, The service for which it provides implementation. We have provided scripts to test out the code on both Windows and Linux platforms. The following example demonstrates testing for an empty or whitespace-only string: When processing data from files, it is often necessary to break up information into individual lines. Let’s go ahead and put this statement into code: We are telling the Java compiler and runtime that our math.util module is exporting the code in the com.packt.math package to any module that depends on math.util. Similiar to BodyHandlers you use BodyPublishers to define the type of data you want to send as body of the request such as strings, byte-arrays, files or input-streams: The last sample demonstrates how to perform authorization via BASIC-AUTH: Collections such as List, Set and Map have been extended with new methods. Modular programming enables one to organize code into independent, cohesive modules, which can be combined to achieve the desired functionality. Let’s start learning Java 11. Running the code is equally simple. This changes with Java 11 – the following methods have been introduced: Let’s have a look at simple examples for a better understanding. Java 10 has introduced a new language keyword var which optionally replaces the type information when declaring local variables (local means variable declarations inside method bodies). Java 11 new helper methods in the class String and the utility class Files. In this series part I introduce a smaller extension in the class java.util.Optional. Let’s take a closer look at this below. Just a single command and everything including the dependency between the modules is taken care of by the compiler. Java 9 introduced a new incubating HttpClient API for dealing with HTTP requests. Of course, this is not possible if the lambda version is used completely without a type. Java 11 is around the corner and many people still use Java 8 in production. To do this, the utility class has java.nio.file.Filesa few extensions in terms of the methods writeString()and readString()get. It is now possible to write or read strings in a file. We can omit the .GET() call as it's the default request method. This is pleasing in that it offers support and updates for a few years, whereas Java 9 and 10 are available through the Oracle’s release policies were only up-to-date for a short period of 6 months and no longer receive any updates. The answer comes from the desire to not have to explicitly specify a type, but nevertheless to be able to define the parameter definitively or to add annotations. You should be wondering what this modularity is all about, and how to create a modular application in Java. Java is an object oriented language and some concepts may be new. Many people (including me) are still using Java 8 in production. The answer is relatively simple: when writing, the mode of overwriting and not appending is not used without surprise. Now, let’s create another module calculator that uses the math.util module. Likes FPS and strategy games. Let's explore what we can do with this API. In this tutorial, we learned to create a simple modular Java application. This tutorial gives a complete understanding of Java. In this book, you will learn how to implement object-oriented designs using classes and interfaces in Java 11. created with. I treat both innovations in separate sections. Such is also found in the classes java.util.function.Predicateas well as in java.util.concurrent.Time-Unit. This brings more consistency to other APIs like those of Collectionand String. With JDK 11 we find Stringthe method in the class lines(), which Streamreturns one and can be used as follows: This method divides the multi-line string into four separate parts, thus outputting: Every now and then you have to tackle a string several times, so to repeat an existing string n times. Now that you have been through the example, we will look at how to generalize it so that we can apply the same pattern in all our modules. September 24, 2018. In this section we’ll start with the new features in various Java 11 APIs. List.copyOf creates an immutable copy of the list. No walls of text, so let's dive right into the code. String strip () – Remove leading and trailing white spaces. As an alternative, you can switch to the OpenJDK . You should also read my Java 8 and Stream API tutorials to learn more modern Java fundamentals. Enjoy! The complete code for this class can be found at Chapter03/2_simple-modular-math-util/math.util/com/packt/math, in the codebase downloaded for this book. From the Java language specification (, a module declaration is of the following form: A module statement is of the following form: We will look at the uses and provides clauses in more detail in the Using services to create loose coupling between the consumer and provider modules recipe. . you can now simply turn optionals into streams or provide another optional as fallback for an empty optional: One of the most basic classes String gets a few helper methods for trimming or checking whitespace and for streaming the lines of a string: Last but not least InputStream finally gets a super useful method to transfer data to an OutputStream, a usecase that's very common when working with streams of raw data. The new HttpClient can be used either synchronously or asynchronously. However if you copy a mutable list, copy is indeed a new instance so it's garanteed there's no side-effects when mutating the original list: When creating immutable maps you don't have to create map entries yourself but instead pass keys and values as alternating arguments: Immutable collections in Java 11 still use the same interfaces from the old Collection API. Finally, in Java 11, another method is added. A valid question! What happens if you pass the value 0? However, it makes its API available for other modules (if not, then this module’s existence is questionable). This is no longer necessary with Java 11. represented time unit into one from the Java 9 introduced Date and Time API: Advanced Java Interview Questions For 5 8 10 Years Experienced, Core Java Interview Questions For Experienced, Java Quiz Questions And Answers For Interviews, What is Machine Learning? The following example demonstrates these methods: Java 11 made it easier to handle strings-related strings. This module has a Calculator class whose work is to accept the user’s choice for which mathematical operation to execute and then the input required to execute the operation. In addition to the link with and()and or()was a negation negate()expressed by. Our example is a simple advanced calculator, which checks whether a number is prime, calculates the sum of prime numbers, checks whether a number is even, and calculates the sum of even and odd numbers. so that you could negate it. Cheers! Before we begin, be sure to read the following practice guide to Oracle’s new licensing policy. The answer comes from the desire to not have to explicitly specify a type, but nevertheless to be able to define the parameter definitively or to add annotations. CTRL + SPACE for auto-complete. But the feature list doesn't end here. In the next part, I introduce the HTTP / 2 API, which left the incubator state with Java 11 and was added to the full-fledged API in the JDK. Java 11 offers one that can be used as follows: In using applications, this leads to a significant increase in readability. Creating a simple modular application in Java 11,, Giving a refresh from Angular Blog – Medium, React Newsletter #232 from’s RSS Feed. Up to and including Java 10, you could either specify all types or omit them in a lambda expression. While Java 10 is more of a cosmetic change, luckily, Java 11 provides a few more new APIs, but I still find the need for the major version to be questionable. This example-driven tutorial covers the most important language and API features from Java 9 to 11. Java 11 Tutorial. During development, the Oracle JDK can still be used free of charge. Our core Java programming tutorial is designed for students and working professionals. In both Java 9 and Java 10, the API has been made a little clearer.