Lambda表达式使用场景

1、集合中的排序效果

// list集合
ArrayList<Person>  list = new ArrayList<>();
list.add(new Person("xiaoming", 12));
list.add(new Person("xiaoli", 11));
list.add(new Person("xiaogang", 15));
// 自定义排序规则
list.sort((o1, o2) -> o2.age - o1.age);
 
 
// set集合
TreeSet<Person> set = new TreeSet<>((o1, o2) -> o1.age - o2.age );
set.add(new Person("xiaoming", 12));
set.add(new Person("xiaoli", 11));
set.add(new Person("xiaogang", 15));
System.out.println(set);

 

 

2、集合中的遍历效果

// 遍历查询
ArrayList<Integer> list = new ArrayList<>();
Collections.addAll(list, 1,2,3,4,5,6,7,8);
list.forEach(ele -> {
    System.out.println(ele);
});
 
// 遍历删除
ArrayList<Integer> list = new ArrayList<>();
Collections.addAll(list, 1,2,3,4,5,6,7,8);
list.removeIf(ele -> {
    // true为删除
    return ele > 4;
});

 

3、线程实例化

Thread t = new Thread(() -> {
    for(int i = 0; i < 100; i++){
        System.out.println("======“ + i);
    }
});
t.start();