Collections

Tags: #◇Computer Science #◇CCPROG3 #◇Collections #◇Code Snippets #◇M4

◇Key Definitions

The Java Collections Framework is a unified architecture for representing and manipulating collections (groups of objects). It contains interfaces, implementations, and algorithms.

◇Theoretical Framework

Core interfaces include:
List: An ordered collection (e.g., ArrayList, LinkedList). Can contain duplicates.
Set: A collection that cannot contain duplicate elements (e.g., HashSet, TreeSet).
Map: An object that maps keys to values (e.g., HashMap, TreeMap). Cannot contain duplicate keys.

◇Code Implementation

import java.util.*;

public class CollectionExample {
    public static void main(String[] args) {
        // List Example
        List<String> list = new ArrayList<>();
        list.add("Apple");
        list.add("Banana");
        
        // Set Example
        Set<Integer> set = new HashSet<>();
        set.add(1);
        set.add(2);
        set.add(1); // Ignored
        
        // Map Example
        Map<String, Integer> map = new HashMap<>();
        map.put("Alice", 90);
        map.put("Bob", 85);
    }
}

◇Syntax Breakdown

<Type>: Generics are used to specify the type of objects the collection will hold, ensuring type safety at compile time.
new ArrayList<>(): The diamond operator <> infers the generic type from the variable declaration.

◇Complexity Analysis

◇References & Navigation

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• Related Notes: ◇Overview of Programming Languages