Book Image

Java 9 Data Structures and Algorithms

By : Debasish Ray Chawdhuri
Book Image

Java 9 Data Structures and Algorithms

By: Debasish Ray Chawdhuri

Overview of this book

Java 9 Data Structures and Algorithms covers classical, functional, and reactive data structures, giving you the ability to understand computational complexity, solve problems, and write efficient code. This book is based on the Zero Bug Bounce milestone of Java 9. We start off with the basics of algorithms and data structures, helping you understand the fundamentals and measure complexity. From here, we introduce you to concepts such as arrays, linked lists, as well as abstract data types such as stacks and queues. Next, we’ll take you through the basics of functional programming while making sure you get used to thinking recursively. We provide plenty of examples along the way to help you understand each concept. You will also get a clear picture of reactive programming, binary searches, sorting, search trees, undirected graphs, and a whole lot more!
Table of Contents (19 chapters)
Java 9 Data Structures and Algorithms
About the Author
About the Reviewer
Customer Feedback


Java has been one of the most popular programming languages for enterprise systems for decades now. One of the reasons for the popularity of Java is its platform independence, which lets one write and compile code on any system and run it on any other system, irrespective of the hardware and the operating system. Another reason for Java's popularity is that the language is standardized by a community of industry players. The latter enables Java to stay updated with the most recent programming ideas without being overloaded with too many useless features.

Given the popularity of Java, there are plenty of developers actively involved in Java development. When it comes to learning algorithms, it is best to use the language that one is most comfortable with. This means that it makes a lot of sense to write an algorithm book, with the implementations written in Java. This book covers the most commonly used data structures and algorithms. It is meant for people who already know Java but are not familiar with algorithms. The book should serve as the first stepping stone towards learning the subject.

What this book covers

Chapter 1, Why Bother? – Basic, introduces the point of studying algorithms and data structures with examples. In doing so, it introduces you to the concept of asymptotic complexity, big O notation, and other notations.

Chapter 2, Cogs and Pulleys – Building Blocks, introduces you to array and the different kinds of linked lists, and their advantages and disadvantages. These data structures will be used in later chapters for implementing abstract data structures.

Chapter 3, Protocols – Abstract Data Types, introduces you to the concept of abstract data types and introduces stacks, queues, and double-ended queues. It also covers different implementations using the data structures described in the previous chapter.

Chapter 4, Detour – Functional Programming, introduces you to the functional programming ideas appropriate for a Java programmer. The chapter also introduces the lambda feature of Java, available from Java 8, and helps readers get used to the functional way of implementing algorithms. This chapter also introduces you to the concept of monads.

Chapter 5, Efficient Searching – Binary Search and Sorting, introduces efficient searching using binary searches on a sorted list. It then goes on to describe basic algorithms used to obtain a sorted array so that binary searching can be done.

Chapter 6, Efficient Sorting – Quicksort and Mergesort, introduces the two most popular and efficient sorting algorithms. The chapter also provides an analysis of why this is as optimal as a comparison-based sorting algorithm can ever be.

Chapter 7, Concepts of Tree, introduces the concept of a tree. It especially introduces binary trees, and also covers different traversals of the tree: breadth-first and depth-first, and pre-order, post-order, and in-order traversal of binary tree.

Chapter 8, More About Search – Search Trees and Hash Tables, covers search using balanced binary search trees, namely AVL, and red-black trees and hash-tables.

Chapter 9, Advanced General Purpose Data Structures, introduces priority queues and their implementation with a heap and a binomial forest. At the end, the chapter introduces sorting with a priority queue.

Chapter 10, Concepts of Graph, introduces the concepts of directed and undirected graphs. Then, it discusses the representation of a graph in memory. Depth-first and breadth-first traversals are covered, the concept of a minimum-spanning tree is introduced, and cycle detection is discussed.

Chapter 11, Reactive Programming, introduces the reader to the concept of reactive programming in Java. This includes the implementation of an observable pattern-based reactive programming framework and a functional API on top of it. Examples are shown to demonstrate the performance gain and ease of use of the reactive framework, compared with a traditional imperative style.

What you need for this book

To run the examples in this book, you need a computer with any modern popular operating system, such as some version of Windows, Linux, or Macintosh. You need to install Java 9 in your computer so that javac can be invoked from the command prompt.

Who this book is for

This book is for Java developers who want to learn about data structures and algorithms. A basic knowledge of Java is assumed.


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