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Java 8 - Streams - Transformations - Map


  • map operation on a stream returns a new stream whose items are transformed.
  • There is also mapToInt, mapToDouble and mapToLong which yield IntStream, DoubleStream and LongStream respectively.

int stream one to three
Stream<Integer> oneToThree = Stream.of(1, 2, 3);

int stream one to two
Stream<Integer> oneToTwo = Stream.of(1, 2);
USAGE

 Stream<Integer> oneToThree_transformed = oneToThree.map(i -> i + 1);

 DoubleStream oneToTwo_transformed = oneToTwo.mapToDouble(i -> i.doubleValue());
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