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Comment by vincnetas | Hacker News Reader

I recently discovered Java streams. Love it and couldn't notice that example readme could be easily written with streams :

  List<ProductDisplayInfo> list = Arrays
    .asList(products)
    .stream()
    .filter(p -> p.getCategory() == 2 || p.getCategory() == 5 && isProductUnderDiscount(p))
    .map(p -> new ProductDisplayInfo(p))
    .collect(Collectors.toList());

https://docs.oracle.com/javase/8/docs/api/java/util/stream/p...

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Java streams are great. Having to go from collections to streams (`.stream()`) and back (`.collect(...)`) is annoying, but understandable from a compositional point of view.

For fun, you can further reduce the size of the code above (and IMO, make it clearer), but using `Arrays.stream(product)` and a method reference for the `map`:

    List<ProductDisplayInfo> list = Arrays
        .stream(products)
        .filter(p -> p.getCategory() == 2 || p.getCategory() == 5 && isProductUnderDiscount(p))
        .map(ProductDisplayInfo::new)
        .collect(Collectors.toList());

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