I saw the class. You already made 10 threads about it. The correct thing to do is to convert it to B4A. There is nothing special in that class.
If you do want to waste some time then compile it into a jar and run desugar to remove the Java 8 features.
Another option is to learn Java and understand how to convert lambdas. It is quite simple.
I solved it using Eclipse. I set the compiler to version 1.7, I linked to the android.jar project from add external jar, after which in the class positioned the cursor on lambda and pressing the yasto ctrl 1 the popup for the conversion appears