Java-enhanced for loop for each

The For-each loop is also called an enhanced for loop, or a foreach Loop.

The For-each loop is a new feature of JDK5.0 (other new features such as generics, auto-boxing, etc.).

The addition of the For-each loop simplifies the traversal of the Collection.

Its syntax is as Follows:

For (type Element:array)

{

System.out.println (element);

}

Disadvantages of the For-each loop: The index information is Discarded.

When traversing a collection or array, if you need to access the index of a collection or array, it is best to use the old-fashioned way to loop or traverse, rather than using an enhanced for loop, because it loses subscript information.

Importjava.util.ArrayList;Importjava.util.Iterator;Importjava.util.List; public classforeachtest{ public Static voidmain (string[] Args) {int[] arr = {1, 2, 3, 4, 5}; System.out.println ("traverse----------------------old way"); //Old Style         for(inti=0; i<arr.length; i++) {System.out.println (arr[i]); } System.out.println ("---------new Way to traverse-------------"); //new style, enhanced for loop         for(intElement:arr)        {System.out.println (element); } System.out.println ("---------traverse a two-dimensional array-------------"); //traversing a two-dimensional array                int[] arr2 = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}} ;  for(int[] Row:arr2) {             for(intElement:row)            {System.out.println (element); }        }                //iterate through the collection list in three different waysList<String> list =NewArraylist<string>(); List.add (A); List.add ("b"); List.add (C); System.out.println ("----------way 1-----------"); //the first way, the normal for loop         for(inti = 0; I < list.size (); i++) {System.out.println (list.get (i)); } System.out.println ("----------way 2-----------"); //the second way, using iterators         for(iterator<string> iter =list.iterator (); Iter.hasnext ();)        {System.out.println (iter.next ()); } System.out.println ("----------way 3-----------"); //Third way, Use the enhanced for loop         for(String Str:list) {System.out.println (str); }    }}

Java-enhanced for loop for each