Java 9 Diamond Operator with Anonymous Inner Classes
Diamond operator ‘<>’ was introduced in Java 7 to make instantiation of generic classes easier.
Java 9 Using effectively-final variables in the try-with-resources
In Java 9 try-with-resources statement has been improved. Now if you already have final or effectively final resource you can use it in try-with-resources statement without need to declare a dummy variable.
Java 9 Disallowed underscore [ _ ] as a one-character identifier
Before Java 9 we could have underscore [ _ ] as a one character identifier.
Java 9 private interface methods
In Java SE 9 interfaces can have private and private static methods.
Java 9 Convenience Factory Methods for Collections
Java 9 enhances the java collections and provides static methods for creating small immutable collection instances.