Java:for loop appears for (int i:arr)

When reading a book, notice that the for loop used by the author appears for (int I:arr), did not contact before, do not know its role, and then wrote a test of its role. It turns out that this is a traversal loop.

1  Public classTest {2      Public Static voidMain (string[] args) {3         int[] arr =New int[] {1, 2, 3};4          for(intI:arr) {5 System.out.println (i);6         }7     }8}

upon access to the information, For (:) {...} The JDK1.5 enhanced for loop is also called For-each. is to facilitate traversal of arrays and collection. Because collection implements the Iterable (iterative) interface, you can use For-each to traverse the container class.

Java:for loop appears for (int i:arr)