To combine 2 HashSets the method addAll()
is used. It is called via a HashSet object and expects a second HashSet object as a parameter. The addAll()
method adds all elements of the specified collection to another collection.
import java.util.HashSet;
class Cube {
public static void main(String[] args) {
HashSet<Integer> set1 = new HashSet<Integer>(),
set2 = new HashSet<Integer>();
set1.add(1);
set1.add(2);
set1.add(3);
set2.add(4);
set2.add(5);
set2.add(6);
// output elements using enhanced for loop
for (Integer s : set1) {
System.out.println(s);
}
System.out.println("Combined sets:");
// Adds all of the elements in the specified collection to this collection (optional operation).
// The behavior of this operation is undefined if the specified collection is modified while
// the operation is in progress. (This implies that the behavior of this call is undefined
// if the specified collection is this collection, and this collection is nonempty.)
set1.addAll(set2);
for (Integer s : set1) {
System.out.println(s);
}
}
}
1
2
3
Combined sets:
1
2
3
4
5
6