Learn about Java nine new features

Java 9 introduced several new features and enhancements, including:

1. Module System: Java 9 introduced a new module system, known as the Java Platform Module System (JPMS), that allows developers to create modular applications. Modules can be used to improve application security, maintainability, and performance.
2. JShell: JShell is a new interactive Java shell that allows developers to quickly prototype and test code snippets without needing to compile a full application.
3. Improved Garbage Collection: Java 9 introduced several improvements to the garbage collection system, including the introduction of the Garbage-First (G1) garbage collector, which can improve performance and reduce pauses.
4. HTTP/2 Client: Java 9 introduced a new HTTP/2 client API that allows developers to make HTTP requests using the HTTP/2 protocol, which can improve performance and reduce latency.
5. Multi-Release JARs: Multi-Release JARs allow developers to create a single JAR file that contains different versions of the same classes, depending on the version of Java that is being used.
6. Process API Updates: Java 9 introduced several updates to the Process API, including the ability to get the process ID of a running process and the ability to get information about all running processes.
7. Collection Factory Methods: Java 9 introduced several new factory methods for creating immutable collections, including List, Set, and Map.
8. Private Interface Methods: Java 9 introduced the ability to define private methods in interfaces, which can be used to reduce code duplication and improve code maintainability.
9. Try-With-Resources Improvements: Java 9 introduced several improvements to the try-with-resources statement, including the ability to declare multiple resources in a single statement and the ability to catch exceptions thrown by the close() method.
10. Stack-Walking API: Java 9 introduced a new Stack-Walking API that allows developers to walk the stack trace of a running application, which can be useful for debugging and profiling.

Overall, Java 9 introduced several new features and improvements that can improve application development and performance.