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package com.cntool.core.map;

import com.cntool.core.map.emau.MinOrMaxEnum;

import java.math.BigDecimal;
import java.util.*;

/**
 * @program: cn-tool
 * @description: map集合工具类
 * @author: ID-Tang
 * @create: 2022-01-18 11:16
 * @copyright: Copyright (c) [2022] [ID-tang]
 * [cntool] is licensed under Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 * http://license.coscl.org.cn/MulanPSL2
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PSL v2 for more details.
 **/
public class MapUtils {
    /**
     * Map是否为空
     *
     * @param map 集合
     * @return 是否为空
     */
    public static boolean isBlank(Map map) {
        return null == map || map.isEmpty();
    }

    /**
     * 获取map集合最大或最小值对应的key
     * 该方法仅用来判断value为BigDecimal类型的Map集合
     *
     * @param map          集合
     * @param minOrMaxEnum 最大最小值枚举类 MIN最小值 MAX最大值
     * @return 最大或最小值的key
     */
    public static String minOrMaxValueKeyBigDecimal(Map map, MinOrMaxEnum minOrMaxEnum) {
        List> list = new ArrayList<>(map.entrySet());
        list.sort(Comparator.comparingDouble(o -> o.getValue().doubleValue()));
        if (MinOrMaxEnum.MIN.equals(minOrMaxEnum)) {
            return String.valueOf(list.get(0).getKey());
        }
        return String.valueOf(list.get(list.size() - 1).getKey());
    }

    /**
     * 获取map集合最大或最小值对应的key
     * 该方法仅用来判断value为Integer类型的Map集合
     *
     * @param map          集合
     * @param minOrMaxEnum 最大最小值枚举类 MIN最小值 MAX最大值
     * @return 最大或最小值的key
     */
    public static String minOrMaxValueKeyInteger(Map map, MinOrMaxEnum minOrMaxEnum) {
        List> list = new ArrayList<>(map.entrySet());
        list.sort(Comparator.comparingInt(Map.Entry::getValue));
        if (MinOrMaxEnum.MIN.equals(minOrMaxEnum)) {
            return String.valueOf(list.get(0).getKey());
        }
        return String.valueOf(list.get(list.size() - 1).getKey());
    }

    /**
     * 求Map中Value(值)的最大值
     *
     * @param map 集合
     * @return 最大值
     */
    public static Object maxValue(Map map) {
        if (isBlank(map)) {
            return null;
        }
        int length = map.size();
        Collection c = map.values();
        Object[] obj = c.toArray();
        Arrays.sort(obj);
        return obj[length - 1];
    }
}