public void start(JmeContext.Type contextType, boolean waitFor) {
        if (context != null && context.isCreated()) {
            logger.warning("start() called when application already created!");
            return;
        }

        if (settings == null) {
            settings = new AppSettings(true);
        }

        logger.log(Level.FINE, "Starting application: {0}", getClass().getName());
        context = JmeSystem.newContext(settings, contextType);
        context.setSystemListener(this);
        context.create(waitFor);
    }
Starts the application.
Creating a rendering context and executing
the main loop in a separate thread.

@param contextType the type of context to create
@param waitFor true&rarr;wait for the context to be initialized,
false&rarr;don't wait
jme3-core/src/main/java/com/jme3/app/LegacyApplication.java