Operate on each element of a Java stream except the maximum value

Question

I am still learning Java streams and could not figure out a solution for my problem.

I have a list of objects which each object has an identifier called stageNo.

I am trying to filter out the max objects according to stageNo and call a method to set a specific value.

code:

Object currentObject = new Object();
List<Object> objects = new ArrayList<>();

objects
       .stream()
       .filter(object -> object.stageNoCalculate == currentObject.getStageNo)
       .filter(object -> object.executionDate != null)
       .max(Comparator.comparing(Object::getStageNo)
       .map(object -> {
            object.setFlag(1);
            return object;
         }).get();

This will result with the object that has the max stageNo and will set the flag method accordingly to 1. This works properly with no issues.

Now I am trying to find each other object that meets the same filtering criteria except the max: find everything apart from max and call setFlag(0) instead.

I am not entirely sure how to do so. I've tried looking for solutions, but I could not find one.

Answer 1

You could sort your stream from max to min, and skip the first element.

objects
  .stream()
  .filter(object -> object.stageNoCalculate == currentObject.getStageNo)
  .filter(object -> object.executionDate != null)
  .sorted(Comparator.comparing(Object::getStageNo).reversed())
  .skip(1) //Skip the first element, which is the max
  .forEach(object -> {
            object.setFlag(0);
            return object;
         });