TreeSet排序规则

自然排序Comparable的使用

使用空参构造方法创建TreeSet集合

自定义的Student类实现Comparable接口，接口对他实现的每一个类创建了一个接口

package algorithm.set;

import java.util.HashSet;

/**
 * @author xiaowang
 * @creat 2024/6/7 23:05
 * @Description Java Lotus
 */
public class HashSetDemo01 {
    public static void main(String[] args) {
        HashSet<String> set=new HashSet<>();
        set.add("html");
        set.add("javascript");
        set.add("java");
        set.add("mysql");

        if(set.contains("html")){
            set.remove("html");
        }

        for (String s : set) {
            System.out.println(s);

        }
    }
}


package algorithm.set;

import java.util.HashSet;

/**
 * @author xiaowang
 * @creat 2024/6/7 23:05
 * @Description Java Lotus
 */
public class HashSetDemo02 {
    public static void main(String[] args) {
        HashSet<Student> studentSet=new HashSet<>();

        studentSet.add(new Student("熊大", 23));
        studentSet.add(new Student("光头强", 24));
        studentSet.add(new Student("熊二", 22));
        studentSet.add(new Student("熊大", 24));

        for (Student student : studentSet) {
            System.out.println(student);

        }
    }
}


package algorithm.set;

import java.util.LinkedHashSet;

/**
 * @author xiaowang
 * @creat 2024/6/7 23:06
 * @Description Java Lotus
 */
public class LinkedHashSetDemo01 {
    public static void main(String[] args) {
        LinkedHashSet<Integer>set=new LinkedHashSet<>();
        set.add(200);
        set.add(300);
        set.add(100);
        set.add(100);

        for (Integer integer : set) {
            System.out.println(integer);

        }
    }
}


package algorithm.set;

/**
 * @author xiaowang
 * @creat 2024/6/7 23:06
 * @Description Java Lotus
 */
public class Student implements Comparable<Student>{
    private String name;
    private int age;
    public Student(){

    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public int compareTo(Student stu) {
        int result = this.name.compareTo(stu.name);
        if(result==0){
            result = this.age - stu.age;
        }


        return result;
    }
}


package algorithm.set;

import java.util.HashSet;
import java.util.Set;

/**
 * @author xiaowang
 * @creat 2024/6/7 23:06
 * @Description Java Lotus
 */
public class SetDemo01 {
    public static void main(String[] args) {
        Set<String>set=new HashSet<>();
        set.add("html");
        set.add("mysql");
        set.add("java");
        set.add("mysql");
        System.out.println(set);

        for (String s : set) {
            System.out.println(s);

        }
    }
}

对于排序的过程中，可能是会出现报错的，使用我们可以去使用comparable接口去进行方法的重载