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I have an ArrayList and want sort it in descending order. I use for it java.util.stream.Stream.sorted(Comparator) method. Here is a description according Java API:
Returns a stream consisting of the elements of this stream, sorted according to the provided
Comparator.
this methods return me a sort with ascending order. Which parameter should I change, just to have the descending order?
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You can use Comparator. reverseOrder() to have a comparator giving the reverse of the natural ordering. If you want to reverse the ordering of an existing comparator, you can use Comparator. reversed() .
naturalOrder(), which returns a Comparator that sorts by placing capital letters first, and String. CASE_INSENSITIVE_ORDER, which returns a case-insensitive Comparator. Basically, in Java 7, we were using Collections. sort() that was accepting a List and, eventually, a Comparator – in Java 8 we have the new List.
You can use Comparator.reverseOrder() to have a comparator giving the reverse of the natural ordering.
If you want to reverse the ordering of an existing comparator, you can use Comparator.reversed().
Sample code:
Stream.of(1, 4, 2, 5) .sorted(Comparator.reverseOrder()); // stream is now [5, 4, 2, 1] Stream.of("foo", "test", "a") .sorted(Comparator.comparingInt(String::length).reversed()); // stream is now [test, foo, a], sorted by descending length If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
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