Functional Programming in Java

Functional Programming in Java
Author: Venkat Subramaniam
Publsiher: Pragmatic Bookshelf
Total Pages: 196
Release: 2014-02-19
Genre: Computers
ISBN: 9781680503548

Download Functional Programming in Java Book in PDF, Epub and Kindle

Intermediate level, for programmers fairly familiar with Java, but new to the functional style of programming and lambda expressions. Get ready to program in a whole new way. Functional Programming in Java will help you quickly get on top of the new, essential Java 8 language features and the functional style that will change and improve your code. This short, targeted book will help you make the paradigm shift from the old imperative way to a less error-prone, more elegant, and concise coding style that's also a breeze to parallelize. You'll explore the syntax and semantics of lambda expressions, method and constructor references, and functional interfaces. You'll design and write applications better using the new standards in Java 8 and the JDK. Lambda expressions are lightweight, highly concise anonymous methods backed by functional interfaces in Java 8. You can use them to leap forward into a whole new world of programming in Java. With functional programming capabilities, which have been around for decades in other languages, you can now write elegant, concise, less error-prone code using standard Java. This book will guide you though the paradigm change, offer the essential details about the new features, and show you how to transition from your old way of coding to an improved style. In this book you'll see popular design patterns, such as decorator, builder, and strategy, come to life to solve common design problems, but with little ceremony and effort. With these new capabilities in hand, Functional Programming in Java will help you pick up techniques to implement designs that were beyond easy reach in earlier versions of Java. You'll see how you can reap the benefits of tail call optimization, memoization, and effortless parallelization techniques. Java 8 will change the way you write applications. If you're eager to take advantage of the new features in the language, this is the book for you. What you need: Java 8 with support for lambda expressions and the JDK is required to make use of the concepts and the examples in this book.

Java Closures and Lambda

Java Closures and Lambda
Author: Robert Fischer
Publsiher: Apress
Total Pages: 220
Release: 2015-03-09
Genre: Computers
ISBN: 9781430259992

Download Java Closures and Lambda Book in PDF, Epub and Kindle

Java Closures and Lambda introduces you to significant new changes to the Java language coming out of what is termed Project Lambda. These new changes make their debut in Java 8, and their highlight is the long-awaited support for lambda expressions in the Java language. You’ll learn to write lambda expressions and use them to create functional interfaces and default methods for evolving APIs, among many other uses. The changes in Java 8 are significant. Syntax and usage of the language are changed considerably with the introduction of closures and lambda expressions. This book takes you through these important changes from introduction to mastery. Through a set of clear examples, you’ll learn to refactor existing code to take advantage of the new language features. You’ll learn what those features can do for you, and when they are best applied. You’ll learn to design and write new code having these important new features in mind from the very beginning. Clearly explains the fantastic benefits resulting from Project Lambda Explains the syntax and IDE support for the new features Shows how to streamline your code by bringing some of the benefits of functional programming to the Java language Illustrates parallelism in closures through Stream and Spliterator objects Explains API evolution by adding methods to existing interfaces without breaking existing interface implementations, a technique addressing potential multiple inheritance issues

Java 8 Lambdas

Java 8 Lambdas
Author: Richard Warburton,Richard Warburton, (Co
Publsiher: "O'Reilly Media, Inc."
Total Pages: 182
Release: 2014-03-18
Genre: Computers
ISBN: 9781449370862

Download Java 8 Lambdas Book in PDF, Epub and Kindle

If you’re a developer with core Java SE skills, this hands-on book takes you through the language changes in Java 8 triggered by the addition of lambda expressions. You’ll learn through code examples, exercises, and fluid explanations how these anonymous functions will help you write simple, clean, library-level code that solves business problems. Lambda expressions are a fairly simple change to Java, and the first part of the book shows you how to use them properly. Later chapters show you how lambda functions help you improve performance with parallelism, write simpler concurrent code, and model your domain more accurately, including building better DSLs. Use exercises in each chapter to help you master lambda expressions in Java 8 quickly Explore streams, advanced collections, and other Java 8 library improvements Leverage multicore CPUs and improve performance with data parallelism Use techniques to “lambdify” your existing codebase or library code Learn practical solutions for lambda expression unit testing and debugging Implement SOLID principles of object-oriented programming with lambdas Write concurrent applications that efficiently perform message passing and non-blocking I/O

Java Closures and Lambda

Java Closures and Lambda
Author: Robert Fischer
Publsiher: Apress
Total Pages: 250
Release: 2015-03-24
Genre: Computers
ISBN: 1430260009

Download Java Closures and Lambda Book in PDF, Epub and Kindle

Java Closures and Lambda introduces you to significant new changes to the Java language coming out of what is termed Project Lambda. These new changes make their debut in Java 8, and their highlight is the long-awaited support for lambda expressions in the Java language. You’ll learn to write lambda expressions and use them to create functional interfaces and default methods for evolving APIs, among many other uses. The changes in Java 8 are significant. Syntax and usage of the language are changed considerably with the introduction of closures and lambda expressions. This book takes you through these important changes from introduction to mastery. Through a set of clear examples, you’ll learn to refactor existing code to take advantage of the new language features. You’ll learn what those features can do for you, and when they are best applied. You’ll learn to design and write new code having these important new features in mind from the very beginning. Clearly explains the fantastic benefits resulting from Project Lambda Explains the syntax and IDE support for the new features Shows how to streamline your code by bringing some of the benefits of functional programming to the Java language Illustrates parallelism in closures through Stream and Spliterator objects Explains API evolution by adding methods to existing interfaces without breaking existing interface implementations, a technique addressing potential multiple inheritance issues

Java Programming 24 Hour Trainer

Java Programming 24 Hour Trainer
Author: Yakov Fain
Publsiher: John Wiley & Sons
Total Pages: 480
Release: 2015-03-30
Genre: Computers
ISBN: 9781118951453

Download Java Programming 24 Hour Trainer Book in PDF, Epub and Kindle

As one of the most popular software languages for building Web applications, Java is often the first programming language developers learn.Completely revised and packed with updates for new versions of Java, the Java Programming 24-Hour Trainer, Second Edition self-paced book + video package provides everything beginners need to get started programming Java with no prior programming experience needed. As with the first edition, Java Programming 24-Hour Trainer features easy-to-follow lessons, reinforced by step-by-step instructions, screencasts, and supplemental exercises, all of which allow readers of all learning styles to master Java programming quickly and painlessly. The more than 10 hours of popular Java programming screencasts from the first edition are completely updated and revised to be more watchable than ever. This edition includes updates for Java SE 8 and Java EE 7 but continues to be useful whatever recent version of Java you choose to learn with. Lessons include: Object-Oriented Programming with Java Class Methods and Constructors Java Syntax: Bits and Pieces Packages, Interfaces, and Encapsulation Programming with Abstract Classes and Interfaces Error handling GUI Basics with Swing Event Handling in Swing GUI GUI Basics with JavaFX - NEW! Developing a game with JavaFX - NEW! Collections Generics Lambda Expressions - NEW! Working with Streams Java Serialization Network Programming Basics Streaming API - NEW! Introduction to Multi-Threading More on Concurrency Working with Databases Using JDBC Rendering Table Data to GUI Annotations and Reflection Remote Method Invocation Java EE 7 Overview - NEW! Programming with Servlets JavaServer Pages Web Applications with WebSockets - NEW! Java Messaging Service Java Naming and Directory Interface Enterprise JavaBeans Java Persistence API RESTful Web Services With JAX-RS Introduction to Spring MVC Framework Introduction to Spring Security - NEW! Build Automation with Gradle - NEW! Java Technical Interviews strong style="color:

Learning Java Lambdas

Learning Java Lambdas
Author: Toby Weston
Publsiher: Packt Publishing Ltd
Total Pages: 114
Release: 2017-03-31
Genre: Computers
ISBN: 9781787281028

Download Learning Java Lambdas Book in PDF, Epub and Kindle

Understand and utilize Java Lambdas About This Book Take a deep dive into one of the single most important additions to modern Java Master Java lambdas, and fully understand functions, classes, and scope. Improve your programming skills, which will enable you to write cleaner and more dynamic code Who This Book Is For Learning Java Lambdas is for developers looking to upgrade their Java skills and familiarize themselves with one of the most important new features of Java. This book is not for absolute beginners and will be more suited to professionals who are already comfortable with Java coding. You should have a basic knowledge of Java before reading this book. What You Will Learn What a lambda is and how it differs from other Java features How to use lambdas effectively in your own projects The use of method references and advanced scoping The difference between lambdas and closures The differences in bytecode produced when using lambdas In Detail In this short book, we take an in-depth look at lambdas in Java, and their supporting features. The book covers essential topics, such as functional interfaces and type inference, and the key differences between lambdas and closures. You will learn about the background to functional programming and lambdas, before moving on to understanding the basic syntax of lambdas and what differentiates these anonymous functions from standard anonymous classes. Lastly, you'll learn how to invoke lambdas and look at the bytecode generated. After reading this book, you'll understand lambdas in depth, their background, syntax, implementation details, and how and when to use them. You'll also have a clear knowledge of the difference between functions and classes, and why that's relevant to lambdas. This knowledge will enable you to appreciate the improvements to type inference that drive a lot of the new features in modern Java, and will increase your understanding of method references and scoping. Style and approach This book is a deep dive into one of the core new features of the Java language – Lambdas. It covers them in great details, making sure that you fully understand how lambdas work, and how they can be put to use in your own programs.

Modern Java in Action

Modern Java in Action
Author: Raoul-Gabriel Urma,Alan Mycroft,Mario Fusco
Publsiher: Simon and Schuster
Total Pages: 592
Release: 2018-09-26
Genre: Computers
ISBN: 9781638356974

Download Modern Java in Action Book in PDF, Epub and Kindle

Summary Manning's bestselling Java 8 book has been revised for Java 9! In Modern Java in Action, you'll build on your existing Java language skills with the newest features and techniques. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Technology Modern applications take advantage of innovative designs, including microservices, reactive architectures, and streaming data. Modern Java features like lambdas, streams, and the long-awaited Java Module System make implementing these designs significantly easier. It's time to upgrade your skills and meet these challenges head on! About the Book Modern Java in Action connects new features of the Java language with their practical applications. Using crystal-clear examples and careful attention to detail, this book respects your time. It will help you expand your existing knowledge of core Java as you master modern additions like the Streams API and the Java Module System, explore new approaches to concurrency, and learn how functional concepts can help you write code that's easier to read and maintain. What's inside Thoroughly revised edition of Manning's bestselling Java 8 in Action New features in Java 8, Java 9, and beyond Streaming data and reactive programming The Java Module System About the Reader Written for developers familiar with core Java features. About the Author Raoul-Gabriel Urma is CEO of Cambridge Spark. Mario Fusco is a senior software engineer at Red Hat. Alan Mycroft is a University of Cambridge computer science professor; he cofounded the Raspberry Pi Foundation. Table of Contents PART 1 - FUNDAMENTALS Java 8, 9, 10, and 11: what's happening? Passing code with behavior parameterization Lambda expressions PART 2 - FUNCTIONAL-STYLE DATA PROCESSING WITH STREAMS Introducing streams Working with streams Collecting data with streams Parallel data processing and performance PART 3 - EFFECTIVE PROGRAMMING WITH STREAMS AND LAMBDAS Collection API enhancements Refactoring, testing, and debugging Domain-specific languages using lambdas PART 4 - EVERYDAY JAVA Using Optional as a better alternative to null New Date and Time API Default methods The Java Module System PART 5 - ENHANCED JAVA CONCURRENCY Concepts behind CompletableFuture and reactive programming CompletableFuture: composable asynchronous programming Reactive programming PART 6 - FUNCTIONAL PROGRAMMING AND FUTURE JAVA EVOLUTION Thinking functionally Functional programming techniques Blending OOP and FP: Comparing Java and Scala Conclusions and where next for Java

Beginning Java 8 Language Features

Beginning Java 8 Language Features
Author: Kishori Sharan
Publsiher: Apress
Total Pages: 704
Release: 2014-08-18
Genre: Computers
ISBN: 9781430266594

Download Beginning Java 8 Language Features Book in PDF, Epub and Kindle

Beginning Java 8 Language Features covers essential and advanced features of the Java programming language such as the new lambda expressions (closures), inner classes, threads, I/O, Collections, garbage collection, streams, and more. Author Kishori Sharan provides over 60 diagrams and 290 complete programs to help you visualize and better understand the topics covered in this book. The book starts with a series of chapters on the essential language features provided by Java, including annotations, inner classes, reflection, and generics. These topics are then complemented by details of how to use lambda expressions, allowing you to build powerful and efficient Java programs. The chapter on threads follows this up and discusses everything from the very basic concepts of a thread to the most advanced topics such as synchronizers, the fork/join framework, and atomic variables. This book contains unmatched coverage of Java I/O, including NIO 2.0, the Path API, the FileVisitor API, the watch service and asynchronous file I/O. With this in-depth knowledge, your data- and file-management programs will be able to take advantage of every feature of Java's powerful I/O framework. Finally, you'll learn how to use the Stream API, a new, exciting addition to Java 8, to perform aggregate operations on collections of data elements using functional-style programming. You'll examine the details of stream processing such as creating streams from different data sources, learning the difference between sequential and parallel streams, applying the filter-map-reduce pattern, and dealing with optional values.

Java Language Features

Java Language Features
Author: Kishori Sharan
Publsiher: Apress
Total Pages: 895
Release: 2018-02-24
Genre: Computers
ISBN: 9781484233481

Download Java Language Features Book in PDF, Epub and Kindle

Work with essential and advanced features of the Java programming language such as Java modules development, lambda expressions (closures), inner classes, threads, I/O, Collections, garbage collection, and more. Author Kishori Sharan provides over 50 diagrams and 290 complete programs to help you visualize and better understand the topics covered in this book. Java Language Features, Second Edition starts with a series of chapters on the essential language features provided by Java, including annotations, reflection, and generics. These topics are then complemented by details of how to use lambda expressions, allowing you to build powerful and efficient Java programs. The chapter on threads follows this up and discusses everything from the very basic concepts of a thread to the most advanced topics such as synchronizers, the fork/join framework, and atomic variables. This book contains unmatched coverage of Java NIO, the Stream API, the Path API, the FileVisitor API, the watch service, and asynchronous file I/O. With this in-depth knowledge, your data- and file-management programs will be able to take advantage of every feature of Java's powerful I/O framework and much more. Additionally, three appendices are available for free via the Download Source Code on apress.com. These appendices will give you a head start on the most important features of Java 10 and the new Java versioning scheme. What You’ll Learn Use essential and advanced features of the Java language Code Java annotations and inner classes Work with reflection, generics, and threads Take advantage of the garbage collector Manage streams with the Stream API Who This Book Is For Those new to Java programming and continues the learning Java journey; it is recommended that you read an introductory Java programming book first, such as Beginning Java Fundamentals, from Apress.

C in Depth

C  in Depth
Author: Jonathan Skeet
Publsiher: Simon and Schuster
Total Pages: 528
Release: 2019-03-07
Genre: Computers
ISBN: 9781638356981

Download C in Depth Book in PDF, Epub and Kindle

Effective techniques and experienced insights to maximize your C# 6 and 7 programming skills Key Features Written by C# legend and top StackOverflow contributor Jon Skeet Unlock the new features of C# 6 and 7 Insights on the future of the C# language Master asynchronous functions, interpolated strings, tuples, and more Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. ”An excellent overview of C# with helpful and realistic examples that make learning the newest features of C# easy.” —Meredith Godar About The Book C# is the foundation of .NET development. New features added in C# 6 and 7 make it easier to take on big data applications, cloud-centric web development, and cross-platform software using .NET Core. Packed with deep insight from C# guru Jon Skeet, this book takes you deep into concepts and features other C# books ignore. C# in Depth, Fourth Edition is an authoritative and engaging guide that reveals the full potential of the language, including the new features of C# 6 and 7. It combines deep dives into the C# language with practical techniques for enterprise development, web applications, and systems programming. As you absorb the wisdom and techniques in this book, you’ll write better code, and become an exceptional troubleshooter and problem solver. What You Will Learn Comprehensive guidance on the new features of C# 6 and 7 Important legacies and greatest hits of C# 2–5 Expression-bodied members Extended pass-by-reference functionality Writing asynchronous C# code String interpolation Composition with tuples Decomposition and pattern matching This Book Is Written For For intermediate C# developers. About The Author Jon Skeet is a senior software engineer at Google. He studied mathematics and computer science at Cambridge, is a recognized authority in Java and C#, and maintains the position of top contributor to Stack Overflow. Table of Contents 1. Survival of the sharpest 2. C# 2 3. C# 3: LINQ and everything that comes with it 4. C# 4: Improving interoperability 5. Writing asynchronous code 6. Async implementation 7. C# 5 bonus features 8. Super-sleek properties and expression-bodied members 9. Stringy features 10. A smörgåsbord of features for concise code 11. Composition using tuples 12. Deconstruction and pattern matching 13. Improving efficiency with more pass by reference 14. Concise code in C# 7 15. C# 8 and beyond PART 1 C# IN CONTEXT PART 2 C# 2–5 PART 3 C# 6 PART 4 C# 7 AND BEYOND

Java SE8 for the Really Impatient

Java SE8 for the Really Impatient
Author: Cay S. Horstmann
Publsiher: Addison-Wesley Professional
Total Pages: 240
Release: 2014-01-10
Genre: Computers
ISBN: 9780133430196

Download Java SE8 for the Really Impatient Book in PDF, Epub and Kindle

Eagerly anticipated by millions of programmers, Java SE 8 is the most important Java update in many years. The addition of lambda expressions (closures) and streams represents the biggest change to Java programming since the introduction of generics and annotations. Now, with Java SE 8 for the Really Impatient , internationally renowned Java author Cay S. Horstmann concisely introduces Java 8’s most valuable new features (plus a few Java 7 innovations that haven’t gotten the attention they deserve). If you’re an experienced Java programmer, Horstmann’s practical insights and sample code will help you quickly take advantage of these and other Java language and platform improvements. This indispensable guide includes Coverage of using lambda expressions (closures) to write computation “snippets” that can be passed to utility functions The brand-new streams API that makes Java collections far more flexible and efficient Major updates to concurrent programming that make use of lambda expressions (filter/map/reduce) and that provide dramatic performance improvements for shared counters and hash tables A full chapter with advice on how you can put lambda expressions to work in your own programs Coverage of the long-awaited introduction of a well-designed date/time/calendar library (JSR 310) A concise introduction to JavaFX, which is positioned to replace Swing GUIs, and to the Nashorn Javascript engine A thorough discussion of many small library changes that make Java programming more productive and enjoyable This is the first title to cover all of these highly anticipated improvements and is invaluable for anyone who wants to write tomorrow’s most robust, efficient, and secure Java code.

JavaFX 9 by Example

JavaFX 9 by Example
Author: Carl Dea,Gerrit Grunwald,José Pereda,Sean Phillips,Mark Heckler
Publsiher: Apress
Total Pages: 557
Release: 2017-09-06
Genre: Computers
ISBN: 9781484219614

Download JavaFX 9 by Example Book in PDF, Epub and Kindle

Create media-rich client applications using JavaFX 9 and the Java 9 platform. Learn to create GUI-based applications for mobile devices, desktop PCs, and even the web. Incorporate media such as audio and video into your applications. Interface with hardware devices such as Arduino and Leap Motion. Respond to gesture control through devices such as the Leap Motion Controller. Take advantage of the new HTTP2 API to make RESTful web requests and WebSockets calls. New to this edition are examples of creating stylized text and loading custom fonts, guidance for working with Scene Builder to create visual layouts, and new content on developing iOS and Android applications using Gluon mobile. The book also covers advanced topics such as custom controls, JavaFX 3D, gesture devices, printing, and animation. Best of all, the book is full of working code that you can adapt and extend to all your future projects. Is your goal to develop visually exciting applications in the Java language? Then this is the book you want at your side. JavaFX 9 by Example is chock-full of engaging, fun-to-work examples that bring you up to speed on the major facets of JavaFX 9. You'll learn to create applications that look good, are fun to use, and that take advantage of the medium to present data of all types in ways that engage the user and lead to increased productivity. The book: Has been updated with new content on modular development, new APIs, and an example using the Scene Builder tool Is filled with fun and practical code examples that you can modify and drop into your own projects Includes an example using Arduino and an accelerometer sensor to track motion in 3D Helps you create JavaFX applications for iOS and Android devices What You'll Learn Work with touch-based interfaces Interpret gesture-based events Use shapes, color, text, and UI controls to create a simple click and point game Add audio and video to your projects Utilize JavaFX 3D Create custom controls using CSS, SVG, and Canvas APIs Organize code into modules using Java Platform Module System (Project Jigsaw) Who This Book Is For Java developers developing visual and media-rich applications to run on PCs, phones, tablets, Arduino controllers, and more. This includes developers tasked with creating visualizations of data from statistical analysis and from sensor networks. Any developer wanting to develop a polished user-interface in Java will find much to like in this book.

Java Programming

Java Programming
Author: Yakov Fain
Publsiher: John Wiley & Sons
Total Pages: 624
Release: 2015-04-28
Genre: Computers
ISBN: 9781118951460

Download Java Programming Book in PDF, Epub and Kindle

Quick and painless Java programming with expert multimedia instruction Java Programming 24-Hour Trainer, 2nd Edition is your complete beginner's guide to the Java programming language, with easy-to-follow lessons and supplemental exercises that help you get up and running quickly. Step-by-step instruction walks you through the basics of object-oriented programming, syntax, interfaces, and more, before building upon your skills to develop games, web apps, networks, and automations. This second edition has been updated to align with Java SE 8 and Java EE 7, and includes new information on GUI basics, lambda expressions, streaming API, WebSockets, and Gradle. Even if you have no programming experience at all, the more than six hours of Java programming screencasts will demonstrate major concepts and procedures in a way that facilitates learning and promotes a better understanding of the development process. This is your quick and painless guide to mastering Java, whether you're starting from scratch or just looking to expand your skill set. Master the building blocks that go into any Java project Make writing code easier with the Eclipse tools Learn to connect Java applications to databases Design and build graphical user interfaces and web applications Learn to develop GUIs with JavaFX If you want to start programming quickly, Java Programming 24-Hour Trainer, 2nd Edition is your ideal solution.

JavaFX 8 Introduction by Example

JavaFX 8  Introduction by Example
Author: Mark Heckler,Gerrit Grunwald,José Pereda,Sean Phillips,Carl Dea
Publsiher: Apress
Total Pages: 420
Release: 2014-06-14
Genre: Computers
ISBN: 9781430264613

Download JavaFX 8 Introduction by Example Book in PDF, Epub and Kindle

JavaFX 8: Introduction by Example shows you how to use your existing Java skills to create graphically exciting client applications with the JavaFX 8 platform. The book is a new and much improved edition of JavaFX 2.0: Introduction by Example, taking you through a series of engaging, fun-to-work examples that bring you up to speed on the major facets of the platform. It will help you to create applications that look good, are fun to use, and that take advantage of the medium to present data of all types in ways that engage the user and lead to increased productivity. Entirely example-based, JavaFX 8: Introduction by Example begins with the fundamentals of installing the software and creating a simple interface. From there, you'll move in progressive steps through the process of developing applications using JavaFX’s standard drawing primitives. You'll then explore images, animations, media, and web. This new edition incorporates the changes resulting from the switch to Java 8 SDK. It covers advanced topics such as custom controls, JavaFX 3D, gesture devices, and embedded systems. Best of all, the book is full of working code that you can adapt and extend to all your future projects. Entirely example-based Filled with fun and practical code examples Covers all that's new in Java 8 relating to JavaFX such as Lambda expressions and Streams Covers gesture devices, 3D display, embedded systems, and other advanced topics

Scala for Java Developers

Scala for Java Developers
Author: Toby Weston
Publsiher: Apress
Total Pages: 245
Release: 2017-12-12
Genre: Computers
ISBN: 9781484231081

Download Scala for Java Developers Book in PDF, Epub and Kindle

Master the fundamentals of Scala and understand its emphasis on functional programming that sets it apart from Java. This book will help you translate what you already know in Java to Scala to start your functional programming journey. Learn Scala is split into four parts: a tour of Scala, a comparison between Java and Scala, Scala-specific features and functional programming idioms, and finally a discussion about adopting Scala in existing Java teams and legacy projects. After reading and using this tutorial, you'll come away with the skills in Scala to kick-start your productivity with this growing popular language. What You'll Learn Tour Scala and learn the basic syntax, constructs, and how to use the REPL Translate Java syntax that you already know into Scala Learn what Scala offers over and above Java Become familiar with functional programming concepts and idioms Gain tips and advice useful when transitioning existing Java projects to Scala Who This Book Is For Java developers looking to transition to Scala. No prior experience necessary in Scala.