To compile and run this demo you will need:
- JDK 17+
- GraalVM
In addition, you will need either a PostgreSQL database, or Docker to run one.
Make sure that both the GRAALVM_HOME
and JAVA_HOME
environment variables have
been set, and that a JDK 17+ java
command is on the path.
See the Building a Native Executable guide for help setting up your environment.
Launch the Maven build on the checked out sources of this demo:
./mvnw package
The Maven Quarkus plugin provides a development mode that supports live coding. To try this out:
./mvnw quarkus:dev
This command will leave Quarkus running in the foreground listening on port 8080.
In this mode you can make changes to the code and have the changes immediately applied, by just refreshing your browser.
Hot reload works even when modifying your JPA entities.
Try it! Even the database schema will be updated on the fly.
When you're done iterating in developer mode, you can run the application as a conventional jar file.
First compile it:
./mvnw package
Next we need to make sure you have a PostgreSQL instance running (Quarkus automatically starts one for dev and test mode). To set up a PostgreSQL database with Docker:
docker run -it --rm=true --name quarkus_test -e POSTGRES_USER=quarkus_test -e POSTGRES_PASSWORD=quarkus_test -e POSTGRES_DB=quarkus_test -p 5432:5432 postgres:13.3
Connection properties for the Agroal datasource are defined in the standard Quarkus configuration file,
src/main/resources/application.properties
.
Then run it:
java -jar ./target/quarkus-app/quarkus-run.jar
Have a look at how fast it boots.
Or measure total native memory consumption...
You can also create a native executable from this application without making any source code changes. A native executable removes the dependency on the JVM: everything needed to run the application on the target platform is included in the executable, allowing the application to run with minimal resource overhead.
Compiling a native executable takes a bit longer, as GraalVM performs additional
steps to remove unnecessary codepaths. Use the native
profile to compile a
native executable:
./mvnw package -Dnative
After getting a cup of coffee, you'll be able to run this binary directly:
./target/spring-data-rest-quickstart-1.0.0-SNAPSHOT-runner