使用Map时进行有序输入

方法

Map map=new LinkedHashMap();

说明

LinkedHashMap继承自 HashMap,具有高效性,同时在 HashMap 的基础上,又在内部增加了一个链表,用以存放元素的顺序

实例


 		Map hashMap=new HashMap();
        hashMap.put("key1","values1");
        hashMap.put("key2","values2");
        hashMap.put("key3","values3");
        hashMap.put("key4","values4");
        hashMap.put("key5","values5");

        log.info("HashMap :{}",JSONObject.toJSONString(hashMap));

        Map map=new LinkedHashMap();

        map.put("key1","values1");
        map.put("key2","values2");
        map.put("key3","values3");
        map.put("key4","values4");
        map.put("key5","values5");

        log.info("LinkedHashMap :{}",JSONObject.toJSONString(map));

输出

HashMap  :{"key1":"values1","key2":"values2","key5":"values5","key3":"values3","key4":"values4"}

LinkedHashMap :{"key1":"values1","key2":"values2","key3":"values3","key4":"values4","key5":"values5"}

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