Java 8 Lambdas - equivalent of c# OfType

Question

I am learning the new java 8 features now, after 4 years exclusively in C# world, so lambdas are on top for me. I am now struggling to find an equivalent for C#\'s \"OfType\" me

Answer 1

There is no exact match in Java for the .OfType() method, but you can use the Java8's filtering features:

IList myNodes = new ArrayList();
myNodes.add(new SpecificNode());
myNodes.add(new OtherNode());

List filteredList = myNodes.stream()
                                         .filter(x -> x instanceof SpecificNode)
                                         .map(n -> (SpecificNode) n)
                                         .collect(Collectors.toList());

If you want to get of the explicit cast, you can do:

List filteredList = myNodes.stream()
                                             .filter(SpecificNode.class::isInstance)
                                             .map(SpecificNode.class::cast)
                                             .collect(Collectors.toList());