Java8之集合(Collection)遍历 forEach()、stream()

list.forEach(System.out::println);

list.forEach(new Consumer<Object>() {
    @Override
    public void accept(Object s) {
        System.out.println(s);
    }
});

list.stream()
        .map(item -> "Mapped_Value_" + item)
        .collect(Collectors.toList()).stream()
        .forEach(System.out::println);

list.stream()
        .filter(item -> item.toString() == "Html")
        .map(item -> "new_" + item)
        .collect(Collectors.toList()).stream()
        .forEach(System.out::println);

/*int sum = widgets.stream()
        .filter(w -> w.getColor() == RED)
        .mapToInt(w -> w.getWeight())
        .sum();*/

System.out.println(" Before JAVA8 ===================================>"); System.out.println(">>>> for loop:"); for (int i = 0; i < list.size(); i++) { System.out.println("list.get(i) = " + list.get(i)); } System.out.println(">>>> for loop enhanced:"); for (String ele : list) { System.out.println("ele = " + ele); } System.out.println(">>>> iterator:"); Iterator<String> iterator = list.iterator(); while (iterator.hasNext()){ System.out.println("iterator.next() = " + iterator.next()); }