Intersection of two strings in Java

Question

Need a Java function to find intersection of two strings. i.e. characters common to the strings.

Example:

String s1 = new String(\"Sychelless\");
St         


        

Answer 1

I have used TreeSet. And retainAll() in TreeSet to get matched elements.

Oracle Doc:

retainAll(Collection c)

Retains only the elements in this set that are contained in the specified collection (optional operation).

String s1 = new String("Sychelless");
String s2 = new String("Sydney");

Set firstSet = new TreeSet();
for(int i = 0; i < s1.length(); i++) {
    firstSet.add(s1.charAt(i));
}

Set anotherSet = new TreeSet();
for(int i = 0; i < s2.length(); i++) {
    anotherSet.add(s2.charAt(i));
}

firstSet.retainAll(anotherSet);
System.out.println("Matched characters are " + firstSet.toString());//print common strings

//output > Matched characters are [S, e, y]