Symmetric difference of two sets in Java

Question

There are two TreeSets in my app:

set1 = {501,502,503,504} set2 = {502,503,504,505} 

I want to get the symmetric difference of these sets so that my output would be the set:

set = {501,505} 

Answer 1

You're after the symmetric difference. This is discussed in the Java tutorial.

Set<Type> symmetricDiff = new HashSet<Type>(set1); symmetricDiff.addAll(set2); // symmetricDiff now contains the union Set<Type> tmp = new HashSet<Type>(set1); tmp.retainAll(set2); // tmp now contains the intersection symmetricDiff.removeAll(tmp); // union minus intersection equals symmetric-difference