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The Map interface is an important part of the Java Collections Framework and represents a key-value mapping. It is used to store and retrieve values based on their associated keys.

One of the commonly used implementations of the Map interface is the HashMap class. The HashMap class provides a hash-based mechanism for storing and accessing key-value pairs.

To use the Map interface with the HashMap class, you first need to import the necessary classes:

TEXT/X-JAVA

1import java.util.HashMap;
2import java.util.Map;

Here's an example of using the Map interface with the HashMap class:

TEXT/X-JAVA

1import java.util.HashMap;
2import java.util.Map;
3
4public class Main {
5    public static void main(String[] args) {
6        // Creating a Map
7        Map<String, Integer> studentScores = new HashMap<>();
8
9        // Adding key-value pairs to the Map
10        studentScores.put("Alice", 95);
11        studentScores.put("Bob", 80);
12        studentScores.put("Charlie", 75);
13
14        // Getting the value for a specified key
15        int aliceScore = studentScores.get("Alice");
16
17        // Updating the value for a specified key
18        studentScores.put("Alice", 90);
19
20        // Removing a key-value pair from the Map
21        studentScores.remove("Charlie");
22
23        // Checking if a specified key exists in the Map
24        boolean containsBob = studentScores.containsKey("Bob");
25
26        // Printing the key-value pairs in the Map
27        for (Map.Entry<String, Integer> entry : studentScores.entrySet()) {
28            String name = entry.getKey();
29            int score = entry.getValue();
30            System.out.println(name + " - " + score);
31        }
32    }
33}

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}
 
import java.util.HashMap;
import java.util.Map;
​
public class Main {
    public static void main(String[] args) {
        // Creating a Map
        Map<String, Integer> studentScores = new HashMap<>();
​
        // Adding key-value pairs to the Map
        studentScores.put("Alice", 95);
        studentScores.put("Bob", 80);
        studentScores.put("Charlie", 75);
​
        // Getting the value for a specified key
        int aliceScore = studentScores.get("Alice");
​
        // Updating the value for a specified key
        studentScores.put("Alice", 90);
​
        // Removing a key-value pair from the Map
        studentScores.remove("Charlie");
​
        // Checking if a specified key exists in the Map
        boolean containsBob = studentScores.containsKey("Bob");
​
        // Printing the key-value pairs in the Map
        for (Map.Entry<String, Integer> entry : studentScores.entrySet()) {
            String name = entry.getKey();
            int score = entry.getValue();

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