利用List和Set添加

1.

package Day09;

public class Worker {
    String name;
    int age;
    double salary;

    public Worker() {
    }

    public Worker(String name, int age, double salary) {
        this.name = name;
        this.age = age;
        this.salary = salary;
    }

    public String getName() {
        return name;
    }

    public int getAge() {
        return age;
    }

    @Override
    public String toString() {
        return "Worker{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", salary=" + salary +
                '}';
    }
}

package Day09;

import java.util.*;
import java.util.stream.Collectors;

public class WorkerTest {
    public static void main(String[] args) {
        List<Worker> list = new ArrayList();
        list.add(new Worker("张三", 18, 20.0));
        list.add(new Worker("李四", 20, 40.0));
        list.add(new Worker("王二", 28, 50.0));
        list.add(new Worker("麻子", 38, 60.0));
        System.out.println(list);
        Collections.sort(list, new Comparator<Worker>() {
            @Override
            public int compare(Worker o1, Worker o2) {
                if (o1.getAge() > o2.getAge()) {
                    return 1;

                } else if (o1.getAge() < o1.getAge()) {
                    return -1;
                } else {
                    return 0;
                }
            }
        });
        Set set = new HashSet();

        set.add(new Worker("张三", 18, 20.0));
        set.add(new Worker("李四", 20, 40.0));
        set.add(new Worker("王二", 28, 50.0));
        set.add(new Worker("麻子", 38, 60.0));
        //迭代器
        for (Iterator itr = set.iterator(); itr.hasNext(); ) {
            System.out.println(itr.next());
        }
        

    }
}