Micronaut Deep Dive presentation by Graeme Rocher at Oracle CodeOne 2019

1. Micronaut Deep Dive
10 Things You Can Do with Micronaut

2. About Me
• Graeme Rocher
• Creator of Grails and Micronaut
• Principal Engineer at Object Computing
• 2018 Oracle Groundbreaker Award Winner
• Java Champion

3. Agenda
• Brief Introduction to Micronaut
• 10 Things You Can Do with Micronaut
• Demos, Demos and more demos
• Summary
• Q & A

4. Micronaut
• A Microservices and Serverless
Focused framework (hence the
branding)
• Also a Complete Application
Framework for any type of
Application
• Dependency Injection, Aspect
Oriented Programming (AOP),
Configuration Management,
Bean Introspection and more..

5. With Micronaut You
Can Build
• Microservices
• Serverless Applications
• Message-Driven Applications with
Kafka/Rabbit
• CLI Applications
• Even Android Applications
• Anything with
static void main(String..args)

6. So What is
Micronaut? Really?
• An Application Framework for the
Future
• Reflection Free, Runtime Proxy Free,
No Dynamic Classloading (in 1.1)
• Ahead of Time (AOT) Compilation
AOT APIs
• ... oh and let's you build
Microservices

7. ONEJust Use Dependency Injection

8. Dependency
Injection
• Reflection and Runtime Proxy Free
• Supports Configuration Injection
• Supports Aspect Oriented
Programming (AOP)
• Constructor, field, method injection
all supported

9. TWOBuild CLI Applications

10. CLI Apps
• Integration with PicoCLI
> https://picocli.info/
• Can use any Micronaunt component,
like the HTTP client.
• Supports going native with GraalVM
for ultra fast execution

11. THREEAs an HTTP Client

12. HTTP Client
• Low level, flexible client
• Also declaring compile time client
• Just declare an interface and have
it implemented for you!
• Uses Micronaut's low overead AOP

13. FOURBuild Microservices

14. FIVEBuild a Native Image with Graal

15. Micronaut Startup and Memory
Runtime Memory Startup
JDK 11 75MB 1.1s
JDK 13 75MB 900ms
JDK 13 + CDS 75MB 400ms
GraalVM Substrate 15MB 21ms

16. SIXGenerate Swagger / Open API

17. Swagger / OpenAPI
Support
• Compilation time computed
• Adds no overhead to the runtime
• Generated YAML can be imported
into Swagger UI
• Or use AutoREST to generate a JS
client

18. SEVENMessage Driven Microservices
with Kafka

19. Kafka Support
• Write headless Microservices that
just
listen for Kafka messages
• Great for real time processing
• Send Kafka messages with
@KafkaClient,
implemented automatically for you.

20. EIGHTQuery with Micronaut Data JDBC

21. Micronaut Data
• Precomputed SQL or JPA-QL
queries
• Uses Micronaut's zero overhead
AOP
• The JDBC implementation
completely reflection free
• Support for Oracle DB, MySQL,
Postgres and SQL Server

22. NINESchedule Jobs

23. TENGather Metrics and Traces

24. Metrics and Tracing
• Tracing: Support for Open Tracing,
Zipkin and Jaeger
• Metrics: Based on Micrometer with
support for
ever metric registry imaginable
• Instrumentation for the whole
framework (client and server
requests)

25. Where to Learn
More
• Website: https://micronaut.io
• Github: https://github.com/
micronaut-projects/micronaut-core
• Comprehensive Guides: https://
guides.micronaut.io
• Talk to us on Gitter: https://gitter.im/
micronautfw

26. Summary
• Micronaut provides a wealth of features
• Tackles a range of uses cases
• General purpose for whatever your needs
• Optimizes for reduced memory usage and startup time
• Works well with Graal native image

27. Q & A