Validation and throwing an exception inside a Flux is not working

Question

I am trying to validate the values of a list using a reactor.core.publisher.Flux inside a try catch, but when map throws the exception the catch doesn't catch it at all. I don't really understand what's happening here. Some help would be appreciate.

This is exactly what I am trying to do:

 public Flux<Something> execute(final List<Line> lines) {
        try {
          return this.getFlux(lines)
              .map(line -> this.validateLine(line))//this throws my custom exception if the condition applies
              .map(line -> this.doSomething(line))
              .map(line -> this.doSomethingElse(line));

        } catch (myCustomException e) {
            return something;
        }
  }

I can see the validate method works well and throws the exception by debugging but the catch doesn't seem to be working and I can't see what is wrong.

Answer 1

You would need a terminal operation applied onto the end of the stream. Streams are evaluated lazily.