org.apache.commons.collections.MapUtils Map集合工具类

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我是靠谱客的博主大气电话，最近开发中收集的这篇文章主要介绍org.apache.commons.collections.MapUtils Map集合工具类，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-collections4</artifactId>
    <version>4.2</version>
</dependency>

包：org.apache.commons.collections4

public static void main(String[] args) {
    // 批量赋值
    Map<String, Object> colorMap = MapUtils.putAll(new HashMap<>(),
            new Object[] { "str", "我是字符串", "boo", true, "num", 1000 });
    System.out.println("colorMap：" + colorMap.toString()); // colorMap：{str=我是字符串, boo=true, num=1000}
    System.out.println("colorMap-isEmpty：" + MapUtils.isEmpty(colorMap)); // colorMap-isEmpty：false
    System.out.println("colorMap-isNotEmpty：" + MapUtils.isNotEmpty(colorMap)); // colorMap-isNotEmpty：true

    // 获取值，还有其他类型可以看MapUtils的API方法
    String str = MapUtils.getString(colorMap, "str");
    System.out.println("str：" + str); // str：我是字符串

    Boolean boo = MapUtils.getBoolean(colorMap, "boo");
    System.out.println("boo：" + boo); // boo：true

    Integer num = MapUtils.getInteger(colorMap, "num");
    System.out.println("num：" + num); // num：1000

    String not = MapUtils.getString(colorMap, "not");
    System.out.println("not：" + not); // not：null

    not = MapUtils.getString(colorMap, "not", "未知");
    System.out.println("not：" + not); // not：未知

    // 为NULL的情况设置值
    colorMap = MapUtils.emptyIfNull(null);
    System.out.println("colorMap：" + colorMap.toString()); // colorMap：{}
    System.out.println("colorMap-isEmpty：" + MapUtils.isEmpty(colorMap)); // colorMap-isEmpty：true
    System.out.println("colorMap-isNotEmpty：" + MapUtils.isNotEmpty(colorMap)); // colorMap-isNotEmpty：false

    // 判断值
    colorMap = null;
    System.out.println("colorMap-isEmpty：" + MapUtils.isEmpty(colorMap)); // colorMap-isEmpty：true
    System.out.println("colorMap-isNotEmpty：" + MapUtils.isNotEmpty(colorMap)); // colorMap-isNotEmpty：false
}