Java9

Java 9, released in September 2017, was a significant update to the Java platform. It introduced several new features and improvements, marking a shift towards modularity and enhanced development capabilities. One of the most prominent features was the Java Platform Module System (JPMS), also known as Project Jigsaw. JPMS allowed developers to break down the Java application into modules, improving maintainability, security, and performance by enabling smaller deployments and reducing the attack surface.

Another key addition was the introduction of the `Optional` class enhancements, which provided new methods like `ifPresentOrElse` and `or` to make working with optional values more expressive and concise. Java 9 also brought improvements to the Stream API, with new methods such as `takeWhile`, `dropWhile`, and `iterate` allowing for more flexible stream processing.

Under the hood, Java 9 included a new garbage collector called the G1 (Garbage-First) collector as the default, aiming to provide more predictable pause times for large heaps. The release also offered HTTP/2 client API, a more efficient and faster way to interact with web servers compared to the previous HTTP/1.1 client. Furthermore, it introduced factory methods for collections, simplifying the creation of immutable collections. Java 9 aimed to lay the groundwork for future Java versions, focusing on modularity and developer productivity.