Module org.jhotdraw8.graph
Package org.jhotdraw8.graph.algo

Interface AddToSet<E>

Type Parameters:
E - the element type of the set.
All Known Subinterfaces:
AddToIntSet
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface AddToSet<E>
A function that adds an element to a set if not already present.

The set can be implemented in various ways. For example:

  • The set can be an implementation of one of the collection classes provided by the Java API. 
             AddToSet<E> = new HashSet<>()::add;
  • The set can be a marker bit on an element object. 
             class Element {
             private boolean marked;
             public boolean mark() {
                 boolean wasMarked = false;
                 marked = true;
                 return wasMarked;
             }
         }
        AddToSet<Element> = Element::mark;

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    add(E e)
    Adds the specified element to the set if it is not already present.

  • Method Details

    • add

      boolean add(E e)
      Adds the specified element to the set if it is not already present.
      Parameters:
      e - element to be added to the set
      Returns:
      true if this set did not already contain the specified element