HashMap的使用

package com.miller.datastructure.precious;

import java.util.HashMap;

import java.util.Iterator;

/**

* @program: data-structure

* @description: 哈希映射的练习

* @author: Miller.FAN

* @create: 2019-09-25 10:16

**/

public class HashMapTest {

public static void main(String[] args) {

HashMap people =new HashMap();

people.put("miller",32);

people.put("son" ,1);

people.put("niu",30);

HashMap miler =new HashMap(10, (float)0.80);

miler.put("google",89);

miler.put(34,"still");

if(miler.isEmpty()) {

System.out.println("miler is empty" + miler.toString());

}

else {

System.out.println("miler has elements, it has " + miler.size() +" 个元素。");

}

// 遍历方法

        Iterator iterator = miler.entrySet().iterator();

while(iterator.hasNext()) {

System.out.println("遍历哈希Map中的元素：" +  iterator.next());

}

//利用 forEach遍历

        for (Object entity: miler.entrySet()

) {

System.out.println("遍历哈希Map中的元素：" +  entity);

}

}

}