{"id":55558,"date":"2022-09-25T14:39:15","date_gmt":"2022-09-25T09:09:15","guid":{"rendered":"https:\/\/www.tothenew.com\/blog\/?p=55558"},"modified":"2022-09-30T14:51:05","modified_gmt":"2022-09-30T09:21:05","slug":"java-transformation-from-java-7-to-java-18","status":"publish","type":"post","link":"https:\/\/www.tothenew.com\/blog\/java-transformation-from-java-7-to-java-18\/","title":{"rendered":"Java Transformation from Java 7 to Java 18"},"content":{"rendered":"

A lot has changed in Java from its beginnings in 1995 until today. Java 8 was a revolutionary release that put Java back on the pedestal of the best programming languages.<\/span><\/p>\n

We will go through most of the changes in the Java language that happened from Java 8 in 2014 until today. I will try to be as brief as possible on every feature. The intention is to have <\/span>a reference for all features between Java 8 and Java 18 inclusively<\/b>.<\/span><\/p>\n

Java 8<\/h2>\n

Java 8 was a massive release, and you can find a list of all features at <\/span>the Oracle website<\/span><\/a>. There are two main feature sets I\u2019d like to mention here:<\/span><\/p>\n

1. Language Features: Lambdas<\/strong><\/p>\n

Before Java 8, whenever you wanted to instantiate, for example, a new Runnable, you had to write an anonymous inner class like so:<\/span><\/p>\n

\"\"<\/p>\n

With lambdas, the same code looks like this:<\/span><\/p>\n

\"\"<\/p>\n

You also got method references, repeating annotations, default methods for interfaces and a few other language features.<\/span><\/p>\n

2. Collections & Streams<\/strong><\/p>\n

In Java 8 you also got functional-style operations for collections, also known as the Stream API. A quick example:<\/span><\/p>\n

\"\"<\/p>\n

Now pre-Java 8 you basically had to write for-loops to do something with that list.<\/span><\/p>\n

With the Streams API, you can do the following:<\/span><\/p>\n

\"\"<\/p>\n

Java 9<\/b><\/h2>\n

Collections<\/b><\/p>\n

Collections got a couple of new helper methods to easily construct Lists, Sets, and Maps.<\/span><\/p>\n

\"\"<\/p>\n

Streams<\/b><\/p>\n

Streams got a couple of additions, in the form of takeWhile,dropWhile,iterate methods.<\/span><\/p>\n

\"\"<\/p>\n

Optionals<\/b><\/p>\n

Optionals got the sorely missed ifPresentOrElse method.<\/span><\/p>\n

\"\"<\/p>\n

Interfaces<\/b><\/p>\n

Interfaces got private methods:<\/span><\/p>\n

\"\"<\/p>\n

Java 10<\/b><\/h2>\n

Local-Variable Type Inference: var-keyword<\/b><\/p>\n

\"\"<\/p>\n

P.S. <\/b>It is still strongly typed, and only applies to variables inside methods.<\/span><\/p>\n

Java 11<\/b><\/h2>\n

New String Methods<\/b><\/p>\n

Adds a few new methods to the String class: isBlank, lines, strip, stripLeading, stripTrailing, and repeat.<\/span><\/p>\n

\"\"<\/p>\n

New File Methods<\/b><\/p>\n

it’s now easier to read and write Strings from files<\/span><\/p>\n

\"\"<\/p>\n

Java 12<\/b><\/h2>\n

Switch Expressions<\/b><\/p>\n

Firstly, let’s look and at the old syntax:<\/span><\/p>\n

\"\"<\/p>\n

And now, let’s see the same logic with switch expressions:<\/span><\/p>\n

\"\"<\/p>\n

It’s also possible to execute code in switch expressions without returning any value:<\/span><\/p>\n

\"\"<\/p>\n

Java 13<\/b><\/h2>\n

Multiline Strings<\/b><\/p>\n

We can finally do this in Java:<\/span><\/p>\n

\"\"<\/p>\n

Java 14<\/b><\/h2>\n

Switch Expressions<\/b><\/p>\n

\"\"<\/p>\n

Records<\/b><\/p>\n

There are now record classes, which help alleviate the pain of writing a lot of boilerplate with Java. <\/span><\/p>\n

Have a look at this pre Java 14 class, which only contains data, (potentially) getters\/setters, equals\/hashcode, toString.<\/span><\/p>\n

\"\"<\/p>\n

With records, it can now be written like this:<\/span><\/p>\n

\"\"<\/p>\n

P.S.<\/b> this is a preview feature and subject to change in future releases.<\/span><\/p>\n

Helpful NullPointerExceptions<\/b><\/p>\n

Finally NullPointerExceptions describe exactly which variable was null.<\/span><\/p>\n

\"\"<\/p>\n

Pattern Matching For InstanceOf\u00a0<\/b><\/p>\n

Previously we had to (cast) our objects inside an instanceof like this<\/span><\/p>\n

\"\"<\/p>\n

We can now do this, effectively dropping the cast.<\/span><\/p>\n

\"\"<\/p>\n

Garbage Collectors<\/b><\/p>\n

The Concurrent Mark Sweep (CMS) Garbage Collector has been removed, and the experimental Z Garbage Collector has been added.<\/span><\/p>\n

Java 15<\/b><\/h2>\n

Text-Blocks \/ Multiline Strings<\/b><\/p>\n

\"\"<\/p>\n

Sealed Classes<\/b><\/p>\n

\"\"<\/p>\n

This means that while the class is public, the only classes allowed to subclass Shape are Circle, Rectangle and Square.<\/span><\/p>\n

Java 16<\/b><\/h2>\n

Vector API Incubator<\/strong><\/p>\n

The idea of this API is to provide a means of vector computations that will ultimately be able to perform more optimally (on supporting CPU architectures) than the traditional scalar method of computations.<\/span><\/p>\n

Let’s look at how we multiply two arrays using vector:<\/span><\/p>\n

\"\"<\/p>\n

Java 17<\/b><\/h2>\n

Java 17 is the new long-term support (LTS) release of Java, after Java 11.<\/span><\/p>\n

Passing Objects as switch functions and check for a particular type.<\/b><\/p>\n

\"\"<\/p>\n

Java 18<\/b><\/h2>\n

@snippet Tag<\/b><\/p>\n

@snippet tag, specifically designed to display source code. With the @snippet tag, we can write the comment as follows:<\/span><\/p>\n

\"\"<\/p>\n

Pattern Matching Improvements:<\/b><\/p>\n

Pattern matching simplifies the implementation of the common pattern of matching an object against a pattern. For example, you may want to check if a given object is an instance of a particular type and then access it in a type-safe manner. This feature improves readability and increases code safety. Pattern matching can be used in switch statements.<\/span><\/p>\n

<\/div>","protected":false},"excerpt":{"rendered":"

A lot has changed in Java from its beginnings in 1995 until today. Java 8 was a revolutionary release that put Java back on the pedestal of the best programming languages. We will go through most of the changes in the Java language that happened from Java 8 in 2014 until today. I will try […]<\/p>\n","protected":false},"author":1488,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":21},"categories":[446],"tags":[5025],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/55558"}],"collection":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/users\/1488"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/comments?post=55558"}],"version-history":[{"count":2,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/55558\/revisions"}],"predecessor-version":[{"id":55634,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/55558\/revisions\/55634"}],"wp:attachment":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/media?parent=55558"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/categories?post=55558"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/tags?post=55558"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}