Advanced Programming | 15. Collections and Generics by Abraham | Learn Smarter
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15. Collections and Generics

The chapter covers the Java Collections Framework and Generics, highlighting their architecture, usage, and best practices for efficient programming. It provides an overview of various collection types like List, Set, Map, along with their core interfaces and common methods. Additionally, it discusses Generics, including their syntax, wildcards, and best practices to ensure type safety and code reusability.

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Sections

  • 15

    Collections And Generics

    This section covers Java's Collections Framework and Generics, focusing on their architecture and applications for efficient data management.

    Learning Practice

  • 15.0

    Introduction

    The introduction highlights Java’s Collections Framework and Generics, which are crucial for effective management of grouped objects in programming.

    Learning Practice

  • 15.1

    The Java Collections Framework Overview

    The Java Collections Framework provides a set of classes and interfaces to store and manipulate groups of objects efficiently.

    Learning Practice

  • 15.1.1

    What Is A Collection?

    A collection is an object that groups multiple elements into a single unit, enabling the storage, retrieval, and manipulation of aggregate data.

    Learning Practice

  • 15.1.2

    Core Interfaces

    Core interfaces in Java Collections Framework facilitate diverse operations on collections of objects.

    Learning Practice

  • 15.2

    List Interface And Its Implementations

    The List interface in Java is an ordered collection that can contain duplicates, with various implementations including ArrayList, LinkedList, Vector, and Stack.

    Learning Practice

  • 15.2.1

    List Interface

    The List interface in Java represents an ordered collection that allows duplicate elements, facilitating dynamic data management.

    Learning Practice

  • 15.2.2

    Implementations

    This section discusses different implementations of the List interface in Java, focusing on ArrayList, LinkedList, Vector, and Stack.

    Learning Practice

  • 15.2.2.1

    Arraylist

    The ArrayList class is a dynamic array-based implementation of the List interface in Java, providing fast random access and flexible storage for elements.

    Learning Practice

  • 15.2.2.2

    Linkedlist

    A LinkedList is a doubly-linked data structure that facilitates efficient insertions and deletions compared to other list implementations in Java.

    Learning Practice

  • 15.2.2.3

    Vector

    The Vector class in Java is synchronized and provides dynamic array capabilities, making it suitable for thread-safe operations.

    Learning Practice

  • 15.2.2.4

    Stack

    A Stack is a LIFO (Last In, First Out) data structure implemented in Java.

    Learning Practice

  • 15.2.3

    Key Methods

    The section discusses the key methods of the List interface in Java's Collections Framework, including their functionalities and importance.

    Learning Practice

  • 15.3

    Set Interface And Its Implementations

    The Set interface in Java defines a collection that eliminates duplicates and is critical for unique data representation.

    Learning Practice

  • 15.3.1

    Set Interface

    The Set Interface in Java represents a collection that does not allow duplicate elements, playing a crucial role in maintaining unique entries.

    Learning Practice

  • 15.3.2

    Implementations

    This section outlines the various implementations of the Set interface in Java's Collections Framework, namely HashSet, LinkedHashSet, and TreeSet.

    Learning Practice

  • 15.3.2.1

    Hashset

    The HashSet class in Java implements the Set interface, allowing for storage of unique elements without any specific order.

    Learning Practice

  • 15.3.2.2

    Linkedhashset

    The LinkedHashSet is an implementation of the Set interface that maintains the order of elements as they are inserted into the collection.

    Learning Practice

  • 15.3.2.3

    Treeset

    A TreeSet in Java is a collection that implements the Set interface and stores elements in a sorted manner, maintaining their natural order or a specified comparator.

    Learning Practice

  • 15.4

    Queue And Deque

    This section covers the Queue and Deque interfaces in Java, explaining their functionality and common implementations.

    Learning Practice

  • 15.4.1

    Queue Interface

    The Queue interface in Java enables data structure operations based on FIFO (First-In-First-Out) order, allowing for efficient task management.

    Learning Practice

  • 15.4.2

    Deque Interface

    The Deque interface in Java provides a double-ended queue that supports FIFO and LIFO operations, allowing elements to be added or removed from both ends.

    Learning Practice

  • 15.4.3

    Implementations

    This section covers the various implementations of the Queue and Deque interfaces in Java, specifically focusing on PriorityQueue and ArrayDeque.

    Learning Practice

  • 15.4.3.1

    Priorityqueue

    The PriorityQueue is a specialized queue implementation in Java that allows elements to be processed based on their priority rather than their order of insertion.

    Learning Practice

  • 15.4.3.2

    Arraydeque

    This section discusses the ArrayDeque, a resizable array implementation of the Deque interface in Java, emphasizing its efficiency and versatility in handling elements from both ends.

    Learning Practice

  • 15.5

    Map Interface And Its Implementations

    The Map interface in Java provides a way to store key-value pairs, allowing for efficient data retrieval.

    Learning Practice

  • 15.5.1

    Map Interface

    The Map interface in Java represents a collection of key-value pairs, ensuring that keys are unique.

    Learning Practice

  • 15.5.2

    Implementations

    This section outlines the various implementations of the Map interface in Java's Collections Framework, detailing their characteristics and uses.

    Learning Practice

  • 15.5.2.1

    Hashmap

    HashMap is a widely used implementation of the Map interface in Java that stores key-value pairs without any defined order.

    Learning Practice

  • 15.5.2.2

    Linkedhashmap

    LinkedHashMap is a part of the Java Collections Framework that maintains the order of insertion while allowing fast access and modification of key-value pairs.

    Learning Practice

  • 15.5.2.3

    Treemap

    TreeMap is a part of Java's Collections Framework that implements the Map interface and maintains key-value pairs in a sorted order based on the natural ordering of keys or a specified comparator.

    Learning Practice

  • 15.5.2.4

    Hashtable

    A Hashtable is a legacy collection in Java, providing synchronized access to a hash-based storage mechanism for key-value pairs.

    Learning Practice

  • 15.5.3

    Common Methods

    This section covers common methods associated with the Map interface in Java, focusing on operations for managing key-value pairs efficiently.

    Learning Practice

  • 15.6

    Iterating Over Collections

    This section discusses various methods available in Java for iterating over collections, including enhanced for-loops, iterators, and streams.

    Learning Practice

  • 15.7

    Algorithms In Collections

    The section discusses various algorithms available in the Collections Framework, enabling efficient manipulation of data structures.

    Learning Practice

  • 15.8

    Comparators And Comparable

    This section introduces the Comparable and Comparator interfaces in Java, focusing on how they enable ordering of objects.

    Learning Practice

  • 15.8.1

    Comparable Interface

    The Comparable interface in Java defines a natural ordering for objects by providing a compareTo method for comparison.

    Learning Practice

  • 15.8.2

    Comparator Interface

    The Comparator interface in Java allows for custom ordering of objects, enhancing flexibility in sorting algorithms beyond natural ordering.

    Learning Practice

  • 15.9

    The Role Of Generics

    Generics in Java enhance type safety, eliminate casting, and promote code reusability.

    Learning Practice

  • 15.9.1

    Why Generics?

    Generics in Java enhance type safety and code reusability by allowing developers to specify object types when creating data structures.

    Learning Practice

  • 15.9.2

    Syntax

    This section introduces the syntax used in Java generics, focusing on how to define and create generic collections.

    Learning Practice

  • 15.9.3

    Generic Methods

    Generic methods in Java allow for type-safe operations on various data types within a single method definition.

    Learning Practice

  • 15.9.4

    Bounded Type Parameters

    Bounded type parameters restrict a generic type to a specific range of classes in Java, enabling greater type safety.

    Learning Practice

  • 15.10

    Wildcards In Generics

    This section covers the concept of wildcards in Java generics, detailing their types and uses for type safety.

    Learning Practice

  • 15.10.1

    Unbounded Wildcards

    Unbounded wildcards in Java generics allow for flexibility in type usage when the specific type is unknown.

    Learning Practice

  • 15.10.2

    Upper Bounded Wildcards

    Upper bounded wildcards allow for the reading of items of a specific type or its subtypes in Java generics.

    Learning Practice

  • 15.10.3

    Lower Bounded Wildcards

    Lower bounded wildcards in Java generics allow for writing items of a specified type or its supertypes.

    Learning Practice

  • 15.10.4

    Pecs Rule

    The PECS rule helps understand how to use wildcards in Java generics effectively, emphasizing that producers should extend and consumers should super.

    Learning Practice

  • 15.11

    Generic Classes And Interfaces

    This section covers the concept of generic classes and interfaces in Java, demonstrating their essential roles in type safety and reusable code.

    Learning Practice

  • 15.11.1

    Generic Class

    A generic class in Java allows for the creation of classes that can operate on typed parameters, enabling type-safe operations.

    Learning Practice

  • 15.11.2

    Generic Interface

    The Generic Interface section introduces the concept of defining interfaces in Java that can operate with different data types using generics.

    Learning Practice

  • 15.12

    Collections Vs Arrays

    This section compares Java Collections and Arrays, highlighting their differences in size, type safety, flexibility, and performance.

    Learning Practice

  • 15.13

    Best Practices

    This section outlines best practices for using Java's Collections Framework and Generics to achieve type safety and performance.

    Learning Practice

  • 15.14

    Summary

    The Java Collections Framework and Generics are essential for managing data groups in Java, ensuring type safety and code reusability.

    Learning Practice

References

Chapter_15_Colle.pdf

Class Notes

Memorization

What we have learnt

  • Collections group multiple ...
  • Generics enhance type safet...
  • Different collection interf...

Final Test

Revision Tests