How to determine whether map is empty in java

The way to determine whether a map is empty in Java is: you can use the isEmpty() function to determine. The isEmpty() function is a system library function in Java that is used to determine whether a certain container has elements. For example, it is used to determine whether ArrayList, HashSet, HashMap has elements, etc.

The way to determine whether a map is empty in Java is to use the isEmpty() function to determine.

(Recommended learning: java introductory program)

Function introduction:

IsEmpty() is used in Java to determine a certain container Is there a system library function for elements. For example, it can be used to determine whether ArrayList, HashSet, HashMap has elements, etc.

In Java, you can use isEmpty(); to determine whether there are elements in a sequence container ArrayList. If there are elements, return a Boolean value false, otherwise return true.

Sample code:

public static void main(String[] args) {
        Map<String, String> map = new HashMap<String, String>();
        System.out.println("map为空：" + map.isEmpty());
        //加入元素
        map.put("1", "1");
        System.out.println("map为空：" + map.isEmpty());
    }

Output result:

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