Concurrent Programming in Java

Go to Course: https://www.coursera.org/learn/concurrent-programming-in-java

Introduction

### Course Review: Concurrent Programming in Java on Coursera **Introduction** If you're delving into the intricacies of software development, understanding concurrent programming is indispensable for effectively managing resources in a multi-threaded environment. "Concurrent Programming in Java" offered through Coursera serves as a robust foundation, especially for learners ranging from students to industry professionals eager to enhance their skills in Java 8. **Course Overview** This course unfolds over three segments, immersing participants in the essential constructs and techniques of concurrent programming. The central theme revolves around how to leverage the capabilities of Java to manage shared resources without the pitfalls of concurrency bugs. Ultimately, by the course's end, learners will grasp a vital skill set that allows them to construct efficient, reliable, and scalable applications. **Syllabus Breakdown** 1. **Welcome to the Course!** - The course kickstarts with an overview of concurrent programming's relevance in modern computing environments. You'll get accustomed to the course structure, including video lectures, coding projects, and demonstrations that enrich the learning experience. 2. **Threads and Locks** - Dive deep into the foundational elements of concurrent programming. This module elaborates on creating and managing threads, synchronization mechanisms, and exploring bugs like deadlock, livelock, and starvation. The engaging study of the "Dining Philosophers" problem helps crystallize these concepts, making them relatable and memorable. 3. **Critical Sections and Isolation** - Here, you'll learn advanced strategies for managing access to shared resources. The critical sections and object-based isolation concepts shed light on how to avoid common concurrency pitfalls. The introduction of Java's atomic variables is particularly insightful, showcasing their practical application and efficiency across different hardware platforms. 4. **Talking to Two Sigma: Using it in the Field** - An engaging video conversation with industry professionals contextualizes the theoretical aspects covered, relating them to real-world applications and challenges in concurrent programming. 5. **Actors** - The course introduces the "Actor" model, emphasizing its distinctiveness from traditional shared-variable models. By eliminating data races, the Actor model provides a fresh perspective on concurrent programming. Practical examples like the Sieve of Eratosthenes algorithm and producer-consumer scenarios demonstrate its utility in design patterns. 6. **Concurrent Data Structures** - A critical examination of concurrent data structures forms the backbone of this module. You'll gain insights into Optimistic Concurrency and experience the implementation complexities of concurrent queues and hash maps. By understanding linearizability, you will appreciate the importance of correctness in concurrent programming. 7. **Continue Your Journey with the Specialization "Parallel, Concurrent, and Distributed Programming in Java"** - As the course wraps up, it encourages learners to explore further into parallel and distributed programming, fostering a comprehensive understanding of complex multi-threading concepts. **Recommendations** Whether you're a seasoned software engineer or a student embarking on your programming journey, "Concurrent Programming in Java" is highly recommended. Its in-depth exploration and practical applications make complex topics accessible and engaging. The blend of theoretical foundations with real-world examples equips learners with the skills to tackle modern software challenges. This course not only enhances your knowledge of Java but also prepares you for the increasingly demanding field of concurrent programming, setting you apart in the tech industry. For anyone looking to upskill or specialize in Java programming for concurrent systems, this course offers an invaluable pathway to mastery. Overall, this course stands out due to its structured approach, comprehensive syllabus, and quality of instruction, making it an essential addition to your educational portfolio on Coursera. Don't miss the opportunity to deepen your understanding of concurrent programming—enroll today!

Syllabus

Welcome to the Course!

Welcome to Concurrent Programming in Java! This course is designed as a three-part series and covers a theme or body of knowledge through various video lectures, demonstrations, and coding projects.

In this module, we will learn about threads and locks, which have served as primitive building blocks for concurrent programming for over five decades. All computing platforms today include some form of support for threads and locks, and make them available for use by developers in a wide range of programming languages. We will learn how threads can be created, joined, and synchronized using structured (e.g., synchronized statements/methods) and unstructured (e.g., java.util.concurrent libraries) locks in Java. We will also learn about new classes of bugs that can arise when concurrent programs need to access shared resources. These bugs are referred to as violations of liveness/progress guarantees, and include deadlock, livelock, and starvation. We will conclude this module by studying different solutions to the classical "Dining Philosophers" problem, and use these solutions to illustrate instances of deadlock, livelock and starvation.

In this module, we will learn different approaches to coordinating accesses to shared resources without encountering the deadlock or livelock bugs studied earlier. Critical/isolated sections are higher-level concurrent programming constructs (relative to locks) that simplify the implementation of mutual exclusion by guaranteeing the absence of deadlocks and livelocks. Object-based isolation relaxes the constraints imposed by critical sections by allowing mutual exclusion to be specified on a per-object basis, as illustrated in the Spanning Tree example. Java's atomic variables represent an important, but restricted, case of object-based isolation that is implemented efficiently on all hardware platforms. Finally, we will learn how object-based isolation can be further relaxed with read/write access modes.

Join Professor Vivek Sarkar as he talks with Software Engineer, Dr. Shams Imam, at their downtown Houston, Texas office about threads, locks, deadlocks, high-level and low-level constructs, and the importance of concurrent programming.

In this module, we will learn another high-level approach to concurrent programming called the "Actor" model. A major difference between the Actor model and the Isolated Sections model is that there are no data races possible in the Actor model because it does not allow for any form of shared variables. However, as in all concurrent programming models, higher-level forms of nondeterminism are still possible in the Actor model due to an inherent asynchrony in the order in which messages may be delivered. We will study multiple examples of concurrency using the Actor model, including the classical Sieve of Eratosthenes algorithm to generate prime numbers, as well as producer-consumer patterns with both unbounded and bounded buffers.

In this module, we will study Concurrent Data Structures, which form an essential software layer in all multithreaded programming systems. First, we will learn about Optimistic Concurrency, an important multithreaded pattern in which two threads can "optimistically" make progress on their assigned work without worrying about mutual conflicts, and only checking for conflicts before "committing" the results of their work. We will then study the widely-used Concurrent Queue data structure. Even though the APIs for using concurrent queues are very simple, their implementations using the Optimistic Concurrency model can be complex and error-prone. To that end, we will also learn the formal notion of Linearizability to better understand correctness requirements for concurrent data structures. We will then study Concurrent Hash Maps, another widely-used concurrent data structure. Finally, we discuss a concurrent algorithm for finding a Minimum Spanning Tree of an undirected graph, an algorithm that relies on the use of Concurrent Data Structures under the covers.

The next two videos will showcase the importance of learning about Parallel Programming and Distributed Programming in Java. Professor Vivek Sarkar will speak with industry professionals at Two Sigma about how the topics of our other two courses are utilized in the field.