public

sanaulla123 / gist:2794193

Last active 2013-03-28

import java.util.*;
public class EnhancedCollections{
  public static void main(String[] args){
    List<Integer> counts = new ArrayList<Integer>();
    for(int i=1;i <= 10; i++){
      counts.add(i);
    }
    
    //Using external iterators
    System.out.println("Using external iterator");
    for(Integer i : counts){
      System.out.print(i+" ");
    }
    System.out.println();
    
    //Using internal iterators
    System.out.println("Using internal iterator");
    counts.forEach(i -> {System.out.print(i*2+" ");});
    System.out.println();
    
    //Printing only Even numbers- Using external iterator
    System.out.println("Printing Even numbers- Using External iterator");
    for ( Integer i : counts){
      if ( i % 2 == 0 ){
        System.out.print(i+" ");
      }
      
    }
    System.out.println();
    
    System.out.println("Printing Even numbers- Using Internal iterator");
    counts.filter(i -> i%2 == 0)
          .forEach(i-> {System.out.print(i+" ");});
    System.out.println();
    
    System.out.println("Odd numbers doubled, a new list created-"+
                      "Using external Iterator");
    List<Integer> newCounts = new ArrayList<Integer>();
    for(Integer i : counts){
        if ( i % 2 != 0 ){
            newCounts.add(i*2);
        }
    }
    for(Integer i : newCounts){
      System.out.print(i+" ");
    }
    System.out.println();
    
    System.out.println("Odd numbers doubled, a new list created-"+
                      "Using internal Iterator");
    List<Integer> newCountsNew = new ArrayList<Integer>();
    counts.filter(i -> i % 2 != 0)
          .map(i -> i*2)
          .into(newCountsNew);
    newCountsNew.forEach(i -> {System.out.print(i+" ");});
    System.out.println();
  }
}