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

s1.contains(s2) returns true;
s1.indexOf(s2) returns 0. 
s1.indexOf("foo") returns -1

For more sophisticated cases use class Pattern.