On September 20, 2022, the most recent version of Java 19, or JDK 19, was published. It includes 7 significant platform advancements that should make developers’ jobs easier.

In this blog, we will go through the major benefits of Java 19 and how it can help you in the long run for top-notch Java development.

A Quick Glance on Java 19

• Structured Concurrency
• Virtual Threads
• A Preview of record pattern
• Foreign Function & Memory API (Preview)
• Pattern Matching for switch
• Vector API
• Port the JDK to Linux/RISC-V (2 incubators and 4 preview features,1 final feature under Hotspot Compiler)

Structured Concurrency (preview)

JEP 428 has two objectives –

• Improve the multithreaded code’s ability to be dependable, observable, and maintainable.
• Promote the use of concurrent programming methods that can lessen common shutdown and cancellation risks, such as thread leaks and cancellation delays.

In Project Loom, Structured Concurrency is also included. By treating many jobs running in distinct threads as a single unit of work, it seeks to make Java concurrent programming simpler. A method provided by JEP 428 enables the division of a task into multiple concurrent subtasks that all end up in the same code block.

Multithreaded programming can be simplified by structured concurrency, a phase of development in which a structured concurrency API is being developed. To streamline error handling and cancellation, multiple tasks are treated as a single unit of work. The lightweight concurrency model introduced in Project Loom improves reliability and observability.

Virtual Threads

Due to their lightweight operation, virtual threads are useful for high-throughput concurrent applications. This preview API will not only allow thread-per-request style applications to scale efficiently, but it will also make it easier to incorporate this API seamlessly into Java.

Additionally, it will make it possible to monitor, debug, and diagnose virtual threads using already-existing JDK tools without changing the fundamental concurrency paradigm for Java or getting rid of the traditional thread execution.

A Preview of record pattern

A sneak peek at record patterns to break down record values. It is possible to nest record forms and type patterns to provide declarative, potent, and modular data processing. The proposal aims to enhance pattern matching to describe more complex, composable data searches without altering type patterns’ syntax or semantics. The pattern matching for instance of the feature introduced in JDK 16 in March 2021 serves as the foundation for this proposal. Record patterns may eventually get access to capabilities like array patterns and vararg patterns. Project Amber, which aims to investigate and develop more compact, Java features that are focused on productivity, includes Record Patterns.

Foreign Function & Memory API (Preview)

Java developers have a few options available when it comes to obtaining off-heap data: Should they choose the safe but inefficient route (ByteBuffer) or should they choose performance above safety (Unsafe)?

A new API in Java 19 enables Java programs to communicate with code and information not included in the Java runtime. The API efficiently executes foreign functions (i.e., code outside the JVM) and securely accesses foreign memory, allowing Java programs to call native libraries and manage native data without the fragility and risk of JNI.

• Consider a superior, pure-Java programming technique rather than the Java Native Interface for ease of use (JNI).
• Offer performance that is comparable to, if not better than, that of currently accessible APIs like JNI and sun.misc.Unsafe.
• Safety – Permit dangerous operations to be carried out by programs on external memory, but by default, notify users of these actions.

Pattern Matching for switch

Pattern matching has been added to Java’s switch expressions and statements. A complex data-oriented query can be constructed succinctly and safely by extending pattern matching to switch, which allows expressions to be checked against a set of patterns with each one having a defined action.

Some of its major goals are –

• Allowing patterns to show in case labels can make switch expressions and statements more helpful and descriptive.
• Whenever necessary, let the switch drop its previous null-hostility.
• By mandating that pattern switch statements cover all potential input values, you can increase the security of switch statements.
• Check that every switch expression and statement presently in use executes and compiles with the same semantics.

Vector API

A new feature will be added to JDK 19, allowing vectors to be stored and loaded from memory segments. It has been incubated in JDK 16, JDK 17, and JDK 18.

This JDK 19 innovation will also add extend and compress, two cross-lane vector operations, along with a companion mask compress function. The query results are filtered with the aid of the compress procedure.

The expansion would be completely inverse of the expansion of the mask-selected lanes from the source vector to the destination vector.

This JDK 19 feature will become clearer and more concise after its fourth iteration, and it will be able to provide a dependable performance of the system and compilation on x64 and AArch64. This API will also work when it is required to do so, by gracefully deteriorating.

Port for Linux/RISC-V (incubator)

In addition to programmatic features, JEP 422 porting OpenJDK to Linux for the RISC-V chip architecture is available. Although there aren’t many RISC-V devices available for purchase right now, this technology seems promising, therefore Java support will be helpful.

As you can see, JDK 19 maintains the Java platform’s regulated pace of development and constant flow of improvements. It’s wonderful to see Java continue to advance and meet developers’ changing needs after 27 years. Java consistently ranks among the top three most widely used languages, which is no surprise.

Good Read: Popular Java Frameworks to Learn in 2022

Wrapping Up

JDK 19 finally introduces virtual threads developed by Project Loom. I’m hoping you’re as eager to employ virtual threads in your projects as I am!

The management of jobs that are divided into parallel subtasks will be substantially simplified by Structured Concurrency, which is still in the incubation stage.

Record patterns are now included in instances and switch’s pattern matching capabilities, which have been incrementally improved in recent JDK releases.

Preview and incubator features “Pattern Matching for Switch”, “Foreign Function & Memory API”, and “Vector API” are being sent to the next preview round.