Kotlin集合—Map/MutableMap

Map：

package com.init.demo.collection

fun main(args: Array) {

    /**
     * Map的定义：mapof(Pair(key,value),Pair(key,value),Pair(key,value),...)
     *  键值对类型 不建议省略 防止圆括号里面的元组Pair初始化时误输入不同的类型
     * 常规属性： size-元素计数  isEmpty -空否
     * 专有属性：entires  代表Map中所有条目组成的set 每一条类型都是Map.Entry
     * Map中的Entry类型定义一个接口（interface） 借口描述了一个如何实现key和value的标准
     * Pair 具体实现需要符合这个接口标准的实体类型
     */
    val airPorts = mapOf(Pair("name","小明"),Pair("age","18")
            ,Pair("gender","男"),Pair("birthday","19930708"),Pair("job","computer")
            ,Pair("city","重庆"),Pair("country","china"),Pair("high","180"),Pair("weight","135"))
    println("获取某个key对应的value：get getOrderDefault 下标方法")
    println(airPorts.get("name"))
    println(airPorts.getOrDefault("sec","您获取错误"))
    println(airPorts["name"])
    println(airPorts["gender"])
    //getOrDefault key有可能不存在或者类型输入错误 查询不到对应的值，就可以输入提示信息
    println("获取所有的key:keys属性")
    println(airPorts.keys)
    println("获取所有的value:values属性")
    println(airPorts.values)
    println("获取所有的条目:entires属性")
    println(airPorts.entries)
    println("检查key和value存在情况:containsKey  containsValue")
    println(airPorts.containsKey("job"))
    println(airPorts.containsValue("computer"))
    //在获取具体的可以和value时，可应用containsKey  containsValue方法先行判断存在性
    //既可以在数组中的高阶函数中使用，也可以在Map中使用
    println("筛选器：filter filterValues filterValues")
    println(airPorts.filter { it.value.contains("computer") })
    println(airPorts.filterValues { it.contains("computer") })
    println(airPorts.filterValues { it.contains("city") })
    //filterNot是filter的变种 不符合条件的筛选出来
    //filterTo  filterNotTo 可以把结果map直接存储到另一个map中
    println(airPorts.filterNot { it.value.contains("computer") })
    println("变形的函数：map")
    val newPorts = airPorts.map { "个性特征："+it.key +"，特征值："+it.value }
    println(newPorts)
    println("变形的key：mapKeys")
    val newPortsKey = airPorts.mapKeys { "个性特征："+it.key  }
    println(newPortsKey)
    println("变形的value：mapValues")
    val newPortsValue = airPorts.mapValues { "特征值："+it.value }
    println(newPortsValue)
    println("极值函数最大值：maxBy")
    println(airPorts.maxBy { it.value.length })
    println("极值函数最小值：mapValues")
    println(airPorts.minBy { it.key.length })
    println("排序 默认按key（字母）来排序：toSortedMap")
    println(airPorts.toSortedMap())
    println("转换成其他集合：toList")
    println(airPorts.toList())
    println("转换成其他集合：toMutableMap")
    println(airPorts.toMutableMap())

    //输出：
    /*获取某个key对应的value：get getOrderDefault 下标方法
    小明
    您获取错误
    小明
    男
    获取所有的key:keys属性
    [name, age, gender, birthday, job, city, country, high, weight]
    获取所有的value:values属性
    [小明, 18, 男, 19930708, computer, 重庆, china, 180, 135]
    获取所有的条目:entires属性
    [name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135]
    检查key和value存在情况:containsKey  containsValue
    true
    true
    筛选器：filter filterValues filterValues
    {job=computer}
    {job=computer}
    {}
    {name=小明, age=18, gender=男, birthday=19930708, city=重庆, country=china, high=180, weight=135}
    变形的函数：map
    [个性特征：name，特征值：小明, 个性特征：age，特征值：18, 个性特征：gender，特征值：男, 个性特征：birthday，
    特征值：19930708, 个性特征：job，特征值：computer, 个性特征：city，特征值：重庆, 个性特征：country，特征值：china,
     个性特征：high，特征值：180, 个性特征：weight，特征值：135]
    变形的key：mapKeys
    {个性特征：name=小明, 个性特征：age=18, 个性特征：gender=男, 个性特征：birthday=19930708, 个性特征：job=computer,
     个性特征：city=重庆, 个性特征：country=china, 个性特征：high=180, 个性特征：weight=135}
    变形的value：mapValues
    {name=特征值：小明, age=特征值：18, gender=特征值：男, birthday=特征值：19930708, job=特征值：computer, city=特征值
    ：重庆, country=特征值：china, high=特征值：180, weight=特征值：135}
    极值函数最大值：maxBy
    birthday=19930708
    极值函数最小值：mapValues
    age=18
    排序 默认按key（字母）来排序：toSortedMap
            {age=18, birthday=19930708, city=重庆, country=china, gender=男, high=180, job=computer, name=小明, weight=135}
    转换成其他集合：toList
    [(name, 小明), (age, 18), (gender, 男), (birthday, 19930708), (job, computer),
     (city, 重庆), (country, china), (high, 180), (weight, 135)]
    转换成其他集合：toMutableMap
    {name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135}*/
}

MutableMap

package com.init.demo.collection

fun main(args: Array) {
    /**
     * MutableMap
     *  定义：mutableMapOf(Pair(key,value),Pair(key,value),Pair(key,value),...)
     */
    val airPorts = mapOf(Pair("name","小明"),Pair("age","18")
            ,Pair("gender","男"),Pair("birthday","19930708"),Pair("job","computer")
            ,Pair("city","重庆"),Pair("country","china"),Pair("high","180"),Pair("weight","135"))
    val muAirPorts = airPorts.toMutableMap()

    println("添加或更新:put 下标")
    muAirPorts["kk"]= "kkhh"
    muAirPorts["AVG"]= "1823"
    muAirPorts.put("TURN","OFF")
    muAirPorts.putIfAbsent("TURN1","ON")
    println(muAirPorts)
    println("添加其他Map:putAll 或 += 两者等价")
    val airPorts1 = mapOf(Pair("name1","小明"),Pair("age1","18")
            ,Pair("gender1","男"),Pair("birthday1","19930708"),Pair("job1","computer"))
    muAirPorts.putAll(airPorts1)
    println(muAirPorts)
    val airPorts2 = mapOf(Pair("name2","小明"),Pair("age2","18")
            ,Pair("gender2","男"),Pair("birthday2","19930708"))
    muAirPorts += airPorts2
    println(muAirPorts)
    println("移除键值对: remove")
    muAirPorts.remove("name2")
    println(muAirPorts)
    println("清空Map: clear")
    muAirPorts.clear()
    println(muAirPorts)

    //输出：
    /*添加或更新:put 下标
    {name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135,
     kk=kkhh, AVG=1823, TURN=OFF, TURN1=ON}
    添加其他Map:putAll 或 += 两者等价
    {name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135,
     kk=kkhh, AVG=1823, TURN=OFF, TURN1=ON, name1=小明, age1=18, gender1=男, birthday1=19930708, job1=computer}
    {name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135,
    kk=kkhh, AVG=1823, TURN=OFF, TURN1=ON, name1=小明, age1=18, gender1=男, birthday1=19930708, job1=computer,
     name2=小明, age2=18, gender2=男, birthday2=19930708}
    移除键值对: remove
    {name=小明, age=18, gender=男, birthday=19930708, job=computer, city=重庆, country=china, high=180, weight=135,
    kk=kkhh, AVG=1823, TURN=OFF, TURN1=ON, name1=小明, age1=18, gender1=男, birthday1=19930708, job1=computer,
    age2=18, gender2=男, birthday2=19930708}
    清空Map: clear
    {}*/


}