Chapter 7. Native mode

By default, not all Charsets are available in native mode.

Charset.defaultCharset(), US-ASCII, ISO-8859-1, UTF-8, UTF-16BE, UTF-16LE, UTF-16

If you expect your application to need any encoding not included in this set or if you see an UnsupportedCharsetException thrown in the native mode, please add the following entry to your application.properties:

quarkus.native.add-all-charsets = true

See also quarkus.native.add-all-charsets in Quarkus documentation.

By default, only the building JVM default locale is included in the native image. Quarkus provides a way to set the locale via application.properties, so that you do not need to rely on LANG and LC_* environement variables:

quarkus.native.user-country=US
quarkus.native.user-language=en

There is also support for embedding multiple locales into the native image and for selecting the default locale via Mandrel command line options -H:IncludeLocales=fr,en, H:+IncludeAllLocales and -H:DefaultLocale=de. You can set those via the Quarkus quarkus.native.additional-build-args property.

Resources accessed via Class.getResource(), Class.getResourceAsStream(), ClassLoader.getResource(), ClassLoader.getResourceAsStream(), etc. at runtime need to be explicitly listed for including in the native executable.

This can be done using Quarkus quarkus.native.resources.includes and quarkus.native.resources.excludes properties in application.properties file as demonstrated below:

quarkus.native.resources.includes = docs/*,images/*
quarkus.native.resources.excludes = docs/ignored.adoc,images/ignored.png

In the example above, resources named docs/included.adoc and images/included.png would be embedded in the native executable while docs/ignored.adoc and images/ignored.png would not.

resources.includes and resources.excludes are both lists of comma separated Ant-path style glob patterns.

Refer to Red Hat build of Apache Camel for Quarkus Extensions Reference for more details.

When using Camel onException handling in native mode, it is your responsibility to register the exception classes for reflection.

For instance, having a camel context with onException handling:

onException(MyException.class).handled(true);
from("direct:route-that-could-produce-my-exception").throw(MyException.class);

The class mypackage.MyException should be registered for reflection. For more information, see Registering classes for reflection.

By default, dynamic reflection is not available in native mode. Classes for which reflective access is needed, have to be registered for reflection at compile time.

In many cases, application developers do not need to care because Quarkus extensions are able to detect the classes that require the reflection and register them automatically.

However, in some situations, Quarkus extensions may miss some classes and it is up to the application developer to register them. There are two ways to do that:

If serialization support is requested via quarkus.camel.native.reflection.serialization-enabled, the classes listed in CamelSerializationProcessor.BASE_SERIALIZATION_CLASSES are automatically registered for serialization.

You can register more classes using @RegisterForReflection(serialization = true).