HashMap - getting First Key value

To get the first key-value pair from a HashMap in Java, you can use the entrySet() method to get a set of the map's entries and then use the iterator() method to get an iterator for the set. You can then use the next() method of the iterator to get the first entry in the set.

Here is an example of how you can get the first key-value pair from a HashMap in Java:

HashMap<String, Integer> map = new HashMap<>();
map.put("key1", 1);
map.put("key2", 2);
map.put("key3", 3);

Map.Entry<String, Integer> firstEntry = map.entrySet().iterator().next();
String firstKey = firstEntry.getKey();
Integer firstValue = firstEntry.getValue();

System.out.println("First key: " + firstKey);
System.out.println("First value: " + firstValue);

In this example, the entrySet() method is used to get a set of the map's entries, and the iterator() method is used to get an iterator for the set. The next() method is used to get the first entry in the set, and the getKey() and getValue() methods are used to get the key and value of the entry.

Keep in mind that the HashMap does not maintain the order of the elements, so the first key-value pair may not be the one that was added first.

I hope this helps! Let me know if you have any questions.