NotificationLikeDO.java

package com.tanpu.community.dao.entity;

import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.TreeSet;

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
public class NotificationLikeDO {

    private Integer count=0;

    private TreeSet<String> set=new TreeSet<>();

    public void addItem(String item) {
        if (this.set.size() >= 3) {
            set.pollFirst();
        }
        set.add(item);
        count++;
    }
}