Make boot faster

Mixer2Engine m2e = new Mixer2Engine();

The above code takes 3-5 seconds. JAXBContext initialization performance causes it. Happily, There are some workaround.

com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.fastBoot system property

The system property can make it faster.

System.setProperty("com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.fastBoot","true");
Mixer2Engine m2e = new Mixer2Engine();

or you can use CLI option 

java -Dcom.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.fastBoot=true ...

Singleton pattern and asynchronous initialization on your application startup code.

public class Mixer2EngineSingleton {

    private Mixer2EngineSingleton() {}

    private static class SingletonHolder {
        private static final Mixer2Engine instance = new Mixer2Engine();
    }

    public static Mixer2Engine getInstance() {
        return SingletonHolder.instance;
    }
}
// in your application startup code (Java8)

CompletableFuture<Mixer2Engine> mixer2EngineCompletableFuture
 = CompletableFuture.supplyAsync(() -> Mixer2EngineSingleton.getInstance());

// other startup sequence...

The above code does NOT interrupt other application start up sequence. Of course, you can combine fastBoot system property with this.

// in other code, use Mixer2Engine from Singleton class.
Mixer2Engine m2e = Mixer2EngineSingleton.getInstance();