Simple tutorial ECMAScript doesn't work (java.lang.NullPointerException)

It doesn’t so much disable as it breaks them.

There is an issue open with a great discussion on how to deal with this problem and a bit on the future or rules development in general.

The important thing to look for there is a post from Yannick with some lines of code that can be added that will nominally make Nashorn scripts work in GraalVM JavaScript too.

However, one has to manually create a folder (there’s an issue open to fix that part) for now to get GraalVM JavaScript to work. There is also a problem getting access to certain OH classes in GraalVM which we don’t yet understand. So I don’t know if GraalVM is ready for general use just yet, but it will be soon hopefully.

@Sergey_Afanasiev, I recommend not installing the GraalVM JavaScript and just using Nashorn, or be patient and wait until these issues GraalVM JavaScript are fixed.