In Java 11 and later, you can use the Map.of factory method to create an immutable Map object with a fixed number of elements.
To create an immutable Map using the Map.of factory method, you can use the following syntax:
Map<KeyType, ValueType> map = Map.of(key1, value1, key2, value2, ...);
Here, KeyType and ValueType are the types of the keys and values in the Map, key1, key2, etc. are the keys, and value1, value2, etc. are the values.
The Map.of factory method returns a Map object that contains the specified key-value pairs.
Here is an example of how you can use the Map.of factory method to create an immutable Map:
Map<String, Integer> map = Map.of("apple", 1, "banana", 2, "cherry", 3);
In this example, the map object is an immutable Map that contains the following key-value pairs: "apple" -> 1, "banana" -> 2, "cherry" -> 3.
It is important to note that the Map.of factory method is available only in Java 11 and later, and it can be used to create Map objects with up to 10 key-value pairs.
If you need to create a Map object with more than 10 key-value pairs, or if you need to create a mutable Map object, you can use the Map interface's put method or the HashMap class's constructor.
For example, to create a mutable Map object using the HashMap class, you can use the following syntax:
Map<String, Integer> map = new HashMap<>();
map.put("apple", 1);
map.put("banana", 2);
map.put("cherry", 3);