What are some examples of using collections in Java?

What are some examples of using collections in Java?

Java Collections Framework provides various classes and interfaces for storing and manipulating groups of objects. For example, you can use an ArrayList to store a dynamic list of items.

Can you give me a code example of using an ArrayList?

Sure! Here's a simple example:

import java.util.ArrayList;

public class Main {
    public static void main(String[] args) {
        ArrayList<String> fruits = new ArrayList<>();
        fruits.add("Apple");
        fruits.add("Banana");
        fruits.add("Cherry");
        System.out.println(fruits);
    }
}

This code creates an ArrayList of fruits and prints it.

What about using a HashMap?

A HashMap is great for storing key-value pairs. Here's an example:

import java.util.HashMap;

public class Main {
    public static void main(String[] args) {
        HashMap<String, Integer> ageMap = new HashMap<>();
        ageMap.put("Alice", 30);
        ageMap.put("Bob", 25);
        System.out.println(ageMap);
    }
}

This code creates a HashMap that associates names with ages.