Find common elements in 2 ArrayLists - Java 7

package commoner;

import java.util.ArrayList;

/**
 *
 * @author srihari
 */
public class Commoner {

    ArrayList<Integer> a1 = new ArrayList<>();
    ArrayList<Integer> a2 = new ArrayList<>();
    ArrayList<Integer> common = new ArrayList<>();
    public void init(){
        for(int i=0;i<101;i++){
            if(i%2 == 0)
                a1.add(i);
            if(i%3 == 0)
                a2.add(i);
        }
    }
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Commoner c = new Commoner();
        c.init();
        for(int i : c.a1){
            if(c.a2.contains(i))
                c.common.add(i);
        }
        System.out.println("Even :: "+c.a1.toString());
        System.out.println("Odd :: "+c.a2.toString());
        System.out.println("Common :: "+c.common.toString());
    }
}