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如何从 hashmap 迭代 object 数组

[英]How to iterate over object array from hashmap

I have two hashmap of type我有两个 hashmap 类型

Hashmap<String,Object[]> hasOne = new Hashmap<String,Object[]>();
Hashmap<String,Object[]> hasTwo = new Hashmap<String,Object[]>();

I've added values in both of them,我在它们中都添加了值,

hasOne.put("anyKey", new Object[1,"Two",3.14]);
hasTwo.put("anyKey", new Object[1,"Two"]);

My requirement is I need to compare values from the object array of both hashmaps and need to print missing data from the object array of the second hashmap ( Ex. 3.14 is missing in the second array on comparing new Object[1,"Two",3.14] && new Object[1,"Two"] ).我的要求是我需要比较两个哈希图的 object 数组中的值,并且需要打印第二个 hashmap 中的object数组中的缺失数据(例如,比较new Object[1,"Two",3.14] && new Object[1,"Two"] )。

Using Arrays.asList(hasOne.get("anyKey"));使用Arrays.asList(hasOne.get("anyKey")); // will get details of object array but i'm not sure how to iterate over that array. // 将获得 object 数组的详细信息,但我不确定如何迭代该数组。

PFB code snippet PFB 代码片段

Map<String, Object[]> one = new HashMap<String, Object[]>();
Map<String, Object[]> two = new HashMap<String, Object[]>();
one.put("firstArray", new Object[]  {1, "Two", 3.14});
two.put("secondArray", new Object[] {1, "Two"});
for(int k=0;k<one.size();k++)
{   
    System.out.println(Arrays.asList(one.get("firstArray")));
}

Try this.尝试这个。 References I used are:我使用的参考文献是:

  1. https://www.javatpoint.com/how-to-compare-two-arraylist-in-java https://www.javatpoint.com/how-to-compare-two-arraylist-in-java
  2. Why do I get an UnsupportedOperationException when trying to remove an element from a List? 尝试从列表中删除元素时,为什么会收到 UnsupportedOperationException?
        // create and insert into maps
        Map<String, Object[]> one = new HashMap<String, Object[]>();
        Map<String, Object[]> two = new HashMap<String, Object[]>();
   
        one.put("firstArray", new Object[]  {1, "Two", 3.14});
        two.put("secondArray", new Object[] {1, "Two"});

        for(int k=0;k<one.size();k++)
        {
            List<Object> arrList1 = new ArrayList<>(Arrays.asList(one.get("firstArray"))); // get the value from the map "one" as arrayList
            List<Object> arrList2 = new ArrayList<>(Arrays.asList(two.get("secondArray"))); // get the value from the map "two" as arrayList
            // System.out.println(arrList1 + " " + arrList2);
            arrList1.removeAll(arrList2); // removes all different values as you require
            System.out.println(arrList1);
        }

I think your requirement is that for each key in the first map you want to find any objects in the value array which are not in the second map:我认为您的要求是,对于第一个 map 中的每个键,您希望在值数组中找到不在第二个 map 中的任何对象:

for (String entry: one.entrySet()) {
    for (Object val: entry.getValue()) {
        if (Arrays.stream(two.get(entry.getKey()).noneMatch(val::equals))) {
            ...
        }
    }
}

You can do all this in nested streams but explicit for loops are easier to understand.您可以在嵌套流中完成所有这些操作,但显式for循环更容易理解。

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