博客

数值集合排序

List<Integer> list = Lists.newArrayList(3, 1, 2, -1);
// 正序
list.sort(Integer::compareTo);
list.forEach((i) -> System.out.println(i));
// 倒叙
list.sort(Comparator.reverseOrder());
list.forEach((i) -> System.out.println(i));
// 正序
list.sort(Comparator.naturalOrder());
list.forEach((i) -> System.out.println(i));

根据对象中的某个属性进行排序

Orange orange = new Orange();
orange.setWeight(1.34);
Orange orange1 = new Orange();
orange1.setWeight(1.2);
Orange orange2 = new Orange();
orange2.setWeight(2.34);
List<Orange> list = Lists.newArrayList(orange, orange1, orange2);
// 正序
// weight属性为基本类型
list1.sort((Orange s, Orange o) -> s.getWeight() > o.getWeight() ? 1 : s.getWeight() == o.getWeight() ? 0 : -1);
// weight属性为封装类型
list1.sort((o1,o2)->o1.getWeight().compareTo(o2.getWeight()));
// 2.34-1.34-1.2
list1.forEach((o) -> System.out.println(o.getWeight()));
// 倒叙
// weight属