Even though Java is one of the most backward-compatible languages and environments I’ve ever worked with, there’s always the possibility of feature deprecations and even removals.

The switch control structure has quite an evolution lately since its inception. First, there were switch expressions (JEP 325, 354, 361). And now, we get pattern matching for switch statements and expressions!

Today we look at Scoped Values, another interesting preview feature that’s incubating since Java 20 (JEP 429). It’s a new way to store and share immutable data with a bounded lifetime within a thread and its child threads.

Dealing with Collections is improving with Java 21, as three new interfaces get retro-fitted right into the existing type hierarchies. These Sequenced Collections give us a uniform API to access the first and last elements, and process Collections in reverse.

Java’s known (and often criticized) for its vast amount of required boilerplate and ceremony for perceived mundane tasks, at least compared to other languages. JEP 445 is explicitly targeted to make the first introduction to Java a breeze, though.

Java’s String type is a ubiquitous type that’s used in every program out there. Over the years, it received many improvements. And now, another exciting improvement is coming that makes String safer and easier to use: String templates.