How to iterate nested lists with lambda streams?

Question

I\'m trying to refactor the following code to lambda expressions with `stream, especially the nested foreach loops:

public static Result match (Response rsp) {
          


        

Answer 1

Try to use map which transform the original source.

   rsp.getFirstNodes().stream().map(FirstNode::getSndNodes)
               .filter(sndNode-> sndNode.isValid())
               .forEach(sndNode->{
   // No do the sndNode parsing operation Here.
   })