import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class Program
{
public static void main(String[] args) {
List<String> arrayList=new ArrayList<String>();
arrayList.add("a");
arrayList.add("b");
Iterator<String> iterator= arrayList.iterator();
while(iterator.hasNext()){
System.out.println(iterator.next());
arrayList.add("c");
}
}
}

import java.util.Collections;
import java.util.Enumeration;
import java.util.Vector;
public class Program
{
public static void main(String[] args) {
Vector<String> vector=new Vector<String>();
vector.add("1");
vector.add("2");
Enumeration<String> listEnum= Collections.enumeration(vector);
while(listEnum.hasMoreElements()){
vector.add("3"); System.out.println(listEnum.nextElement());

}
}
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
class Employee{
String name;
public Employee(){}
public Employee(String name){
this.name=name;
}
public String toString(){
return "name"+name;
}
static class comparatorName implements Comparator<Employee>{
public int compare(Employee obj1,Employee obj2){
return obj1.name.compareTo(obj2.name);
}
}
}
public class Program
{
public static void main(String[] args) {
Employee e1=new Employee("ankit");
Employee e2=new Employee("brad");

ArrayList<Employee> list=new ArrayList<Employee>();
list.add(e1);
list.add(e2);
Collections.sort(list,new Employee.comparatorName());
System.out.println(list);
}
}