New exciting features in Java 9
In September, Oracle released Java SE 9 with more than 150 new features. The latest version of the widely used programming language comes with several new features and APIs to speed up app development for devices large and small. At the same time, the features provided by Java 9 help developers improve application performance, security, and maintainability. Therefore, it becomes essential for programmers to understand some of the key features provided by Java 9.
What do programmers need to know about Java 9?
system module
Developers can now use Better Support for HTML5 and JavaScript to split the JDK into multiple modules. Each modular JAR file contains a module descriptor. Developers can define the interdependence of various modules through required declarations. Modularity makes it easy for programmers to run JVM modules seamlessly on small devices that lack additional memory. At the same time, they can also run only the APIs and JVM modules required by the application.
early build
Java 9 significantly improves the process of compiling code through early compilation (AOT). Developers can take advantage of AOT compilation that compiles Java classes into native code even before the virtual machine starts them. AOT compilation improves the performance of applications large and small by overcoming the major shortcomings of just-in-time (JIT) compilation. Unlike JIT compilation, AOT compilation ensures that no Java method is left uncompiled.
Real-Eval-Print-Loop Tool
Java 9 ships with a new real-eval-print-loop (REPL) command-line tool: Shell. The shell is designed with functions to evaluate declarations and declarative expressions interactively. A programmer can use the shell to assess the quality of Java code before compilation. You can simply enter a code snippet and collect feedback. Shell even has the ability to complete tabs and add required terminal semicolons automatically. The new REPL tool makes Java compete with widely used programming languages like Python and Scala.
Better support for HTML5 and JavaScript
The enhanced Javadoc documentation tool provided by Java 9 has the ability to generate HTML5 markup. Additionally, the latest version of the programming language supports several new characters, blocks, and scripts as part of the Unicode 8.0 encoding standard. At the same time, Java 9 comes with an improved lightweight JavaScript engine that makes it easier for programmers to embed JavaScript code into Java applications. Developers can further enable parsing of ECMAScript code in various IDEs and frameworks directly with the parser API for the Nashorn ECMAScript syntax tree provided by the JDK.
Improved streaming API
While writing Java code, programmers use strings to express calculations. Java 8 accelerated stream processing by providing the Streams API. Java 9 comes with an enhanced version of the Streams API that allows developers to pick and drop items from the Stream based on specific conditions by adding methods. Additionally, the enhanced Streams API is designed with features for creating a stream for nullable value and iterating over Stream elements.
Multiple Resolution Image API
Java 9 introduces a new interface, MultiResolutionImage, for creating a single multi-resolution image by encapsulating multiple images with different resolutions. Developers can also use the multi-resolution image API provided by Java 9 to get multiple variants of a single image. Also, they can use the API to select a particular image based on the required resolution. Therefore, Java programmers can now use a single API to create a unified multi-resolution image and get resolution-specific image variants.
http://2 client API
Java 9 completely changed the way applications make HTTP calls. Replaces the HttpURLConnection API with a new HTTP client API. The HTTP client API supports both http://2 and WebSockets. However, the API is currently not part of Java SE. It is implemented as an incubator module that lives under the jdk.incubtor namespace. But the HTTP Client API supports the latest communication standards and overcomes the shortcomings of the HttpURLConnection API.
stack traversal API
While writing Java code, programmers explore ways to access and filter stack trances efficiently. The latest version of Java simplifies stack traversal by providing the stack traversal API. The new API makes it easier for developers to access and filter stack trace information. In addition, it is compatible with short and long walks. Thus, it becomes easier for programmers to access and filter the entire stack without relying on the virtual machine to capture the stack information.
Datagram Transport Layer Security (DTLS) API
Java 9 helps developers build secure applications by providing an API for Datagram Transport Layer Security (DTLS). The API keeps communication between the client and the server secure by eliminating the possibilities of data manipulation, message forgery, and eavesdropping. In addition, it provides communication privacy to a variety of applications that use the Datagram Transport Protocol (DTP). Despite being built on Transport Layer Security (TLS), DTLS implements the SSL protocol.
Improved process API
Java programmers often find it overwhelming to control and manage operating system processes. The process API provided by a previous version of developers to access native code and write additional code. But the improved process API provided by Java 9 makes it easier for programmers to control and consume operating system processes. They can use the API to make a Java application interact directly with the operating system. In addition, they can take advantage of new methods to handle process names and states without writing additional code.
deprecated functions
Despite providing several new features, Java 9 does not support some of the features provided by Java 8. For example, it no longer supports the Applet API. Tea Java web developers you have to switch from Applet API to Java Web Start to launch applications from web browsers. Similarly, Java 8 speeds up the development of garbage collectors in the HotSpot virtual machine by deprecating Concurrent Mark Sweep (CMS) garbage collectors. When using the latest version of Java, developers also lack the option to receive Java warnings on import statements and select JRE at release time.
Overall, Java 9 comes with several new features to simplify application development for devices large and small. However, some of the binaries and sources introduced by Java 9 are not compatible with earlier versions of the programming language. Developers even have to make various code changes and update libraries while migrating existing applications to Java 9. But developers should consider upgrading their existing applications to Java 9 to take advantage of these new features and enhancements. Java developers should also use these highly recommended tools for better programming.