Building a Native Image

Download GraalVM and install it (add the bin dir to you path and set the JAVA_HOME to point to GraalVM). You can also use sdkman to download it. You will need GraalVM 1.0.0-rc5.

Then build an image:

$ native-image --no-server -H:Name=target/app -H:ReflectionConfigurationFiles=graal-netty.json,graal-sample.json -Dio.netty.noUnsafe=true -H:+ReportUnsupportedElementsAtRuntime -Dfile.encoding=UTF-8 -cp ".:$(echo target/dependency/BOOT-INF/lib/*.jar | tr ' ' ':')":target/dependency/BOOT-INF/classes:target/dependency com.example.FuApplication

Then run it:

$ ./target/app

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::

...
14:30:45.278 [reactor-http-nio-1] DEBUG reactor.netty.tcp.TcpServer - [id: 0xdc9e0f8b, L:/0:0:0:0:0:0:0:0:8080] Bound new server
14:30:45.278 [main] INFO org.springframework.boot.web.embedded.netty.NettyWebServer - Netty started on port(s): 8080
14:30:45.278 [main] INFO org.springframework.boot.SpringApplication - Started application in 0.013 seconds (JVM running for 0.013)

You can add -H:IncludeResources='META-INF/spring.factories|org/springframework/boot/logging/.*' and also add the graal-boot.json reflection config file to the list, if you want to see what happens with the full Boot init sequence:

$ native-image --no-server -H:Name=target/app -H:ReflectionConfigurationFiles=graal-netty.json,graal-boot.json,graal-sample.json -Dio.netty.noUnsafe=true -H:+ReportUnsupportedElementsAtRuntime -Dfile.encoding=UTF-8 -cp ".:$(echo target/dependency/BOOT-INF/lib/*.jar | tr ' ' ':')":target/dependency/BOOT-INF/classes:target/dependency -H:IncludeResources='META-INF/spring.factories|org/springframework/boot/logging/.*' com.example.FuApplication
$ ./target/app -Dorg.springframework.boot.logging.LoggingSystem=org.springframework.boot.logging.java.JavaLoggingSystem

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::

...
14:30:45.278 [reactor-http-nio-1] DEBUG reactor.netty.tcp.TcpServer - [id: 0xdc9e0f8b, L:/0:0:0:0:0:0:0:0:8080] Bound new server
14:30:45.278 [main] INFO org.springframework.boot.web.embedded.netty.NettyWebServer - Netty started on port(s): 8080
14:30:45.278 [main] INFO org.springframework.boot.SpringApplication - Started application in 0.013 seconds (JVM running for 0.013)