Can Java 8 Streams operate on an item in a collection, and then remove it?

Question

Like just about everyone, I\'m still learning the intricacies (and loving them) of the new Java 8 Streams API. I have a question concerning usage of streams. I\'ll provide a

Answer 1

I see Paul's clarity concern when using streams, stated in the top answer. Perhaps adding explaining variable clarifies intentions a little bit.

set.removeIf(item -> {
  boolean removeItem=item.qualify();
  if (removeItem){
    item.operate();
  }
  return removeItem;
});

Answer 2

After the operation, they serve no further purpose, and should be removed from the original set. The code works well, but I can't shake the feeling that there's an operation in Stream that could do this for me, in a single line.

You cannot remove elements from the source of the stream with the stream. From the Javadoc:

Most stream operations accept parameters that describe user-specified behavior..... To preserve correct behavior, these behavioral parameters:

• must be non-interfering (they do not modify the stream source); and
• in most cases must be stateless (their result should not depend on any state that might change during execution of the stream pipeline).