Updated 27 Aug
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Collections in Java
Gain insights into Java Collections Framework. Delve into lists, sets, and hashmaps. Learn about data modification, sorting, thread-safety, and internal workings for efficient usage.
4.6
57 lessons
5h
Created by Saurav Aggarwal
What's included
- 57 lessons across 12 modules
- 5 quizzes with instant feedback
- AI Tutor on every lesson
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What You'll Learn
- Identify core Java collection interfaces and distinguish Collection from the Collections utility class
- Implement ArrayList operations: insert, retrieve, update, remove, and iterate safely with Iterator/ListIterator
- Sort lists using Collections.sort or streams with Comparable and Comparator (lambdas and anonymous classes)
- Use LinkedList and explain its node-based structure and time complexity for common operations
- Apply Set types (HashSet, TreeSet) to manage uniqueness, iterate, sort, and solve duplicate-detection tasks
- Manipulate Map types (HashMap, TreeMap, LinkedHashMap) including iteration, sorting, and key design with equals/hashCode
- Use Arrays and Collections utilities for searching, sorting, copying, min/max, unmodifiable, and thread-safe wrappers
Learning Roadmap
1.
Let's Begin
Let's Begin
Get familiar with Java collections, their types, functions, and usage for better coding.
2.
Lists in Java
Lists in Java
Get started with managing, iterating, and sorting ArrayLists, and applying basic operations.
3.
LinkedList in Java
LinkedList in Java
2 Lessons
2 Lessons
Examine Java's LinkedList structure, operations, methods for fetching, removing, and sorting elements.
4.
CopyOnWriteArrayList in Java
CopyOnWriteArrayList in Java
3 Lessons
3 Lessons
Enhance your skills in using CopyOnWriteArrayList for thread-safe Java collections.
5.
Sets in Java
Sets in Java
6 Lessons
6 Lessons
Solve problems in creating, managing, and iterating HashSet; identify duplicates efficiently.
6.
TreeSet in Java
TreeSet in Java
4 Lessons
4 Lessons
Follow the process of creating, managing, and solving problems using TreeSets in Java.
7.
HashMap In Java
HashMap In Java
10 Lessons
10 Lessons
Master the steps to create, update, and optimize HashMaps, including key design and iteration.
8.
TreeMap in Java
TreeMap in Java
4 Lessons
4 Lessons
Step through creating, inserting, fetching, removing, and sorting elements in Java TreeMap.
9.
LinkedHashMap in Java
LinkedHashMap in Java
2 Lessons
2 Lessons
Explore the structure and behavior of LinkedHashMap, maintaining insertion order in Java collections.
10.
Additional Map Implementations
Additional Map Implementations
3 Lessons
3 Lessons
Work your way through ConcurrentHashMap, IdentityHashMap, and EnumMap for efficient and specialized Map usage.
11.
Arrays Class
Arrays Class
5 Lessons
5 Lessons
Grasp the fundamentals of Java's Arrays class, including searching, sorting, copying, and performing operations.
12.
Collections Class
Collections Class
5 Lessons
5 Lessons
Make Java collections efficient and secure with min, max, and thread-safe methods.
Certificate of Completion
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About this course
WHY I WROTE THIS COURSE
Collection is one of the most important topics for Java programming. Without the proper knowledge of every collection type in Java, it becomes difficult for you to decide which option to pick in a particular scenario.
This course will give you a great understanding of all collection types available in the Collections Framework like lists, linked lists, sets, and hashmaps.
After completing this course, you will know how data can be modified within a collection, how to sort a collection, and how it can be made thread-safe. You will also cover the internal working of each Java collection so you can work with them more efficiently.
ABOUT THE AUTHOR
Saurav Aggarwal
Extensive experience of 10 years working on technologies like Java, Spring, Hibernate, Web Services, Redis, Kafka and AWS.
Trusted by 3.1 million developers working at companies
A
Anthony Walker
@_webarchitect_
E
Evan Dunbar
ML Engineer
S
Software Developer
Carlos Matias La Borde
S
Souvik Kundu
Front-end Developer
V
Vinay Krishnaiah
Software Developer
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