iterator on list

Sun Oct 21, 2012 12:28 pm

Iterator on java list

Code:: import java.util.ArrayList; import java.util.Iterator; import java.util.List; public class Main { /** * @param args the command line arguments */ public static void main(String[] args) { List<Float> floatList = new ArrayList<Float>(); for (float num = 0; num < 1; num+=0.05) { floatList.add(num); } Iterator listIterator = floatList.iterator(); while (listIterator.hasNext()) // check if it has next { System.out.println(listIterator.next()); } } }

the output is :

Code:: 0.0 0.05 0.1 0.15 0.2 0.25 0.3 0.35000002 0.40000004 0.45000005 0.50000006 0.5500001 0.6000001 0.6500001 0.7000001 0.7500001 0.80000013 0.85000014 0.90000015 0.95000017

You can also fill the list using random class:

Code:: List<Float> floatList = new ArrayList<Float>(); for (float num = 0; num < 1; num+=0.05) { floatList.add(new Random().nextFloat()*num); } Iterator listIterator = floatList.iterator(); while (listIterator.hasNext()) // check if it has next { System.out.println(listIterator.next()); }

You can use for loop (for keyword) with iterator like this:

Code:: Iterator listIterator = floatList.iterator(); for (;listIterator.hasNext();) // check if it has next { System.out.println(listIterator.next()); }

You can work on element by element like this (with generic data type added to the iterator):

Code:: Iterator<Float> listIterator = floatList.iterator(); while (listIterator.hasNext()) // check if it has next { Float fnum= listIterator.next(); fnum+=0.1f; System.out.println(fnum); }