Virtual Threads Spring Demo

This repository contains a Spring demo application using "Virtual Threads", a feature described in JEP 444 and released in Java 21.

The application has two controllers:

• ControllerEvolution1_Sequential: sequential code on platform threads or virtual threads
• ControllerEvolution2_CompletableFuture: asynchronous code using CompletableFuture

Start the application in dev mode using:

mvn spring-boot:run

Then query the endpoints using:

curl localhost:8080/stage1-seq/product/1
curl localhost:8080/stage2-cf/product/1

To switch to virtual threads, uncomment the two bean definitions in SpringVirtualThreadTestApplication.java, then access this endpoint again:

curl localhost:8080/stage1-seq/product/1

Within IntelliJ, you can also open the endpoints-test.http file to run the HTTP requests.

Other Java 21 Examples

You might also find these GitHub repositories interesting:

Virtual Threads:

• https://github.com/SvenWoltmann/virtual-threads
• https://github.com/SvenWoltmann/virtual-threads-quarkus

Structured Concurrency:

• https://github.com/SvenWoltmann/scoped-values

Scoped Values:

• https://github.com/SvenWoltmann/scoped-values

Pattern Matching for Switch:

• https://github.com/SvenWoltmann/pattern-matching-for-switch

Additional Resources

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