Java_基础—TreeMap集合键是Student值是String的案例

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Student类，属性为name,age
实现接口Comparable，重写comparTo()方法，通过年龄的大小进行排序实现

public class Student implements Comparable<Student>{        @Override        public int compareTo(Student o) {            int num = this.age - o.age;            return num == 0 ? this.name.compareTo(o.name) : num;        }       }

TreeMap类

package com.soar.map;import java.util.Comparator;import java.util.TreeMap;import com.soar.bean.Student;public class Demo7_TreeMap {    /*     * * A:案例演示     * TreeMap集合键是Student值是String的案例     */    public static void main(String[] args) {        //comparator();        TreeMap<Student,String> tm = new TreeMap<>(new Comparator<Student>(){            @Override            public int compare(Student s1, Student s2) {                int num = s1.getName().compareTo(s2.getName());     //按照姓名的Unicode码比较                return num == 0 ? s1.getAge() - s2.getAge() : num;            }           });        tm.put(new Student("张三",23),"北京");        tm.put(new Student("李四",24),"上海");        tm.put(new Student("王五",25),"广州");        tm.put(new Student("赵六",26),"深圳");        System.out.println(tm);         //在Student对象类中重写comparTo方法，按照年龄的大小比较进行排序    }    private static void comparator() {        TreeMap<Student,String> tm = new TreeMap<>();        tm.put(new Student("张三",23),"北京");        tm.put(new Student("李四",24),"上海");        tm.put(new Student("王五",25),"广州");        tm.put(new Student("赵六",26),"深圳");        System.out.println(tm);    }}

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