jdk1.8表达式学习

package 域名.client;

import 域名.*;
import 域名域名icate;
import 域名域名ector;
import 域名域名ectors;
import 域名域名am;

/**
 * @author liyongqiang
 * @title: Test1
 * @description: TODO
 * @date 2019/9/209:43
 */
public class Test1 {

    public static void main(String[] args) {
        List<User> list=new ArrayList<>();
        域名(new  User("1","张三","一年级",95));
        域名(new  User("2","李四","二年级",96));
        域名(new  User("3","王五","三年级",97));
        域名(new  User("4","朱留","四年级",100));

        //遍历
        域名ach((o)-> 域名tln(""+域名ring()));
        //遍历
        域名ach(o-> 域名tln(""+域名ring()));
        //转 hashSet
        Set<User> set1=域名am().collect(域名t());
        //转  hashSet
        Set<String> set2=域名am().map(User::getName).collect(域名t());

        //转treeSet
        TreeSet<String> set3=域名am().map(User::getName).collect(域名llection(TreeSet::new));

        //转 map
        Map<String,String> map1=域名am().collect(域名p(User::getId,User::getLevel));

        //转map
        Map<String,String> map2=域名am().collect(域名p(User::getId,User::getName,(token, token2) -> token));

        //分组
        Map<String,List<User>> map3=域名am().collect(域名pingBy(User::getName));

        //分组count

        Map<String,Long> map4=域名am().collect(域名pingBy(User::getName,域名ting()));

        //分组求和

        Map<String,Integer>map5=域名am().collect(域名pingBy(User::getName,域名ingInt(User::getScore)));


        //过滤条件
        List<User> temp1=域名am().filter(o->"1".equals(域名d())).collect(域名st());

        //多个过滤条件
        Predicate<User> scoFilter=(o)->(域名core()>25);
        Predicate<User> clsFilter=(o)->("三年级".equals(域名evel()));
        List<User> temp2=域名am().filter(scoFilter).filter(clsFilter).collect(域名st());

        //取前多少个
        List<User> temp3=域名am().limit(2).collect(域名st());


        //升序排序
        List<User>temp4=域名am().sorted((u1,u2)->(域名core()-域名core())).collect(域名st());

        //降序排序
        List<User>temp5=域名am().sorted((u1,u2)->(域名core()-域名core())).collect(域名st());

        //升序 第一个
        User user1=域名am().max((u1,u2)->(域名core()-域名core())).get();


        //降序第一个
        User user2=域名am().min((u1,u2)->(域名core()-域名core())).get();


        //求和
        int  sum=域名llelStream().mapToInt(p->域名core()).sum();

        IntSummaryStatistics stats=域名am().mapToInt((x)->域名core()).summaryStatistics();

        域名tf("最大的数字"+域名ax());
        域名tf("最小的数字"+域名in());
        域名tf("所有数字的综合"+域名um());
        域名tf("所有数字的平均值"+域名verage());







    }


}
class User{
    private  String id;
    private String name;
    private  String  level;
    private   int   score;

    public User(String id, String name, String level, int score) {
        域名 = id;
        域名 = name;
        域名l = level;
        域名e = score;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        域名 = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        域名 = name;
    }

    public String getLevel() {
        return level;
    }

    public void setLevel(String level) {
        域名l = level;
    }

    public int getScore() {
        return score;
    }

    public void setScore(int score) {
        域名e = score;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=\'" + id + \'\\'\' +
                ", name=\'" + name + \'\\'\' +
                ", level=\'" + level + \'\\'\' +
                ", score=" + score +
                \'}\';
    }
}