How to compare 2 Strings that have different content in them..

Question

I have 2 Strings:
String st1 = "1,2,3,4,6,7,9,10,11";
String st2 = "4,5,10,11";
I want to compare these 2 Strings where the result should be. Basically, any item from st2 is in st1: String res = "4,10,11";
How can I do this in an efficient way?
I was thinking of using StringTokenizer on st2 and compare each item to st1.... any help is appreciated. Thanks.

Answer 1

import java.util.ArrayList;
import java.util.Iterator;
import java.util.StringTokenizer;
* @author BADRINARAYAN
public class stringTok {
public static void main(String[] ar)
    String st1 = "1,2,3,4,6,7,9,10,11";
    String st2 = "4,5,10,11";
    TreeSet<String> value=new TreeSet<String>();
    ArrayList<String> set1=new ArrayList<String>();
    ArrayList<String> set2=new ArrayList<String>();
    StringTokenizer s1=new StringTokenizer(st1,",");
    StringTokenizer s2=new StringTokenizer(st2,",");
    while(s1.hasMoreTokens())
        set1.add(s1.nextToken());
    while(s2.hasMoreTokens())
        set2.add(s2.nextToken());
    for(Iterator it1=set1.iterator();it1.hasNext();)
        String temp1=it1.next().toString();
        for(Iterator it2=set2.iterator();it2.hasNext();)
            if(temp1.equals(it2.next().toString()))
                value.add(temp1);
    System.out.println(value);
}Edited by: badri.m on Feb 15, 2010 3:25 AM