How to implement a reverse mapping Java using lambdas? -


As far as I know, in Java 8, the mapping works as follows

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For example:

  List & lt; String & gt; ObjList = Arrays.asList ("1," 2, 3, 4, 5, 6, 7); ObjList.stream (). Map (i - & gt; i) For every (i -> System.out.print ("+ i)");   

Output:

  1 2 3 4 5 6 7   

But my question is: how Can I reverse mapping? Like

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Then it will be output

  7 6 5 4 3 2 1   

Or is it not possible to do this?

In this example, I submit the list to one.

Enters Linkedist (Double End Quote) which allows me to attach items to the last-in-first-out (LIFO) order.

I store the collected method using Linkedist List :: Adjust that reads the item, close the section at the top of the list.

  public static zero main (last string ... args) {final list & lt; String & gt; ObjList = Arrays.asList ("1," 2, 3, 4, 5, 6, 7); Last list & lt; String & gt; Reverse = objList.stream () .collect (linked list: new, linked list: addFirst, linkedlist: addAll); // [7, 6, 5, 4, 3, 2, 1] System.out.println (reverse); }   

The solution below is OK, but I do not like to close the original list.

  public static zero main (final string .. rgs) {final list & lt; String & gt; ObjList = Arrays.asList ("1," 2, 3, 4, 5, 6, 7); Last list & lt; String & gt; Reversed = IntStream.range (- (objList.size) - 1), 1) .mapToObj (i -> objList.get (-i)) .collect (collectors list); // [7, 6, 5, 4, 3, 2, 1] System.out.println (reverse); }    

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