LinkedHashMap 反向遍历

import java.util.*;

public class Test {

    public static void main(String[] args) {
//        Map hashMap = new HashMap<>(16);
//        for(int i=0;i<10000;i++){
//            hashMap.put(i+"",i);
//        }
//        for(Map.Entry entry : hashMap.entrySet()){
//            System.out.println("key:"+entry.getKey()+",value:"+entry.getValue());
//        }

        Map linkedHashMap = new LinkedHashMap<>(16);
        for (int i = 0; i < 10000; i++) {
            linkedHashMap.put(i + "", i);
        }
        for (Map.Entry entry : linkedHashMap.entrySet()) {
            System.out.println("key:" + entry.getKey() + ",value:" + entry.getValue());
        }

        System.out.println("============================");

        // 使用的是迭代器 ListIterator
        ListIterator.Entry> i=
                new ArrayList.Entry>(
                        linkedHashMap.entrySet()).listIterator(linkedHashMap.size());
        while(i.hasPrevious()) {
            Map.Entry entry=i.previous();
            System.out.println("key:" + entry.getKey() + ",value:" + entry.getValue());
        }



    }
}

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