SimpleFileBridge.java

public static void main(String... args) throws MuleException {
    Mule myMule = Mule.newInstance(new MyModule());

    myMule.start(); //start mule
}

public static class MyModule extends AbstractModule { // config module
    @Override
    protected void configure() {
        flow("SimpleFilePollAndMove") //defines a named flow
            .from("file:///opt/my_app/out") //source folder
            .send("file:///opt/other_app/in"); //destiny folder
    }
}