public static void main(String[] args) throws IOException { Path path = Paths.get("../alice.txt"); String contents = new String(Files.readAllBytes(path), StandardCharsets.UTF_8); Stream<String> words = Stream.of(contents.split("[\\P{L}]+")); show("words", words); Stream<String> song = Stream.of("gently", "down", "the", "stream"); show("song", song); Stream<String> silence = Stream.empty(); silence = Stream.<String>empty(); // Explicit type specification show("silence", silence); Stream<String> echos = Stream.generate(() -> "Echo"); show("echos", echos); Stream<Double> randoms = Stream.generate(Math::random); show("randoms", randoms); Stream<BigInteger> integers = Stream.iterate(BigInteger.ONE, n -> n.add(BigInteger.ONE)); show("integers", integers); Stream<String> wordsAnotherWay = Pattern.compile("[\\P{L}]+").splitAsStream(contents); show("wordsAnotherWay", wordsAnotherWay); try (Stream<String> lines = Files.lines(path, StandardCharsets.UTF_8)) { show("lines", lines); } }
static <T> Stream<T> inOrder(Tree<T> tree) { if (tree.isLeaf()) { return Stream.of(tree.getValue()); } else { final List<Node<T>> children = tree.getChildren(); return children .tail() .foldLeft(Stream.<T>empty(), (acc, child) -> acc.appendAll(inOrder(child))) .prepend(tree.getValue()) .prependAll(inOrder(children.head())); } }
static <T> Stream<T> preOrder(Tree<T> tree) { return tree.getChildren() .foldLeft(Stream.of(tree.getValue()), (acc, child) -> acc.appendAll(preOrder(child))); }