Domain-Driven Design Using Naked Objects
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Learning Functional Programming in Scala Alvin Alexander
Learning Functional Programming in Scala Alvin Alexander A logical, step by step approach to learning functional programming Copyright Learning Functional Programming in Scala Copyright 2017 Alvin J. Alexander All rights reserved. No part of this book may be reproduced without prior written permission from the author. Disclaimer: This book is presented solely for educational purposes, and it’s also a work in progress. While best efforts have been used in prepar- ing this book, the author makes no representations or warranties of any kind and assume no liabilities of any kind with respect to the accuracy or completeness of the contents, and specifically disclaim any implied war- ranties of merchantability or fitness of use for a particular purpose. The author shall not be held liable or responsible to any person or entity with respect to any loss or incidental or consequential damages caused, or al- leged to have been caused, directly or indirectly, by the information or programs contained herein. Any use of this information is at your own risk. The advice and strategies contained herein may not be suitable for your situation. Version 0.1.1, published May 15, 2017 (The cover photo was taken on the Dalton Highway in Alaska, some- where between Fairbanks and Prudhoe Bay.) Contents 1 Changelog 1 2 Preface 3 3 Introduction (or, Why I Wrote This Book) 5 4 WhoThisBookisFor 11 5 Goals 15 6 Question Everything 23 7 Rules for Programming in this Book 33 8 One Rule for Reading this Book 39 9 What is “Functional Programming”? 41 10 What is This Lambda -
Design Pattern Interview Questions
DDEESSIIGGNN PPAATTTTEERRNN -- IINNTTEERRVVIIEEWW QQUUEESSTTIIOONNSS http://www.tutorialspoint.com/design_pattern/design_pattern_interview_questions.htm Copyright © tutorialspoint.com Dear readers, these Design Pattern Interview Questions have been designed specially to get you acquainted with the nature of questions you may encounter during your interview for the subject of Design Pattern. As per my experience good interviewers hardly plan to ask any particular question during your interview, normally questions start with some basic concept of the subject and later they continue based on further discussion and what you answer: What are Design Patterns? Design patterns represent the best practices used by experienced object-oriented software developers. Design patterns are solutions to general problems that software developers faced during software development. These solutions were obtained by trial and error by numerous software developers over quite a substantial period of time. What is Gang of Four GOF? In 1994, four authors Erich Gamma, Richard Helm, Ralph Johnson and John Vlissides published a book titled Design Patterns - Elements of Reusable Object-Oriented Software which initiated the concept of Design Pattern in Software development. These authors are collectively known as Gang of Four GOF. Name types of Design Patterns? Design patterns can be classified in three categories: Creational, Structural and Behavioral patterns. Creational Patterns - These design patterns provide a way to create objects while hiding the creation logic, rather than instantiating objects directly using new opreator. This gives program more flexibility in deciding which objects need to be created for a given use case. Structural Patterns - These design patterns concern class and object composition. Concept of inheritance is used to compose interfaces and define ways to compose objects to obtain new functionalities. -
Naked Objects: a Technique for Designing More Expressive Systems
Naked objects: a technique for designing more expressive systems Richard Pawson Robert Matthews Computer Sciences Corporation NakedObjects.org and Computer Science Department, Tdnity College, Dublin, IE rpawson@csc;com ABSTRACT OOUIs provide a number of advantages to the user including Naked objects is an approach to systems design in which core reduced modality [6], and greater expressiveness for the user business objects show directly through to the user interface, and [10], and have become the norm for 'creative' applications such in which all interaction consists of invoking methods on those as drawing, computer aided design (CAD), page make-up and objects in the noun-verb style. One advantage of this approach multimedia editing. OOUIs are far less common in transactional is that it reaults in systems that arc more expressive from the business systems. This may be because the need for viewpoint of the user: they treat the user like a problem solver, expressiveness is less clear. It may also be because the not as merely a process-follower. Another advantage is that the underlying structure of most transactional business applications, 1:1 mapping between the user's representation and the comprising scripted procedures and data operations, does not underlying model means that it is possible to auto-generate the map well onto an OOUI. former from the latter, which yields benefits to the development Surprisingly, though, even where a transactional business process. The authors have designed a Java-based, open source system is based upon a true business object model, the core toolkit called Naked Objects which facilitates this style of business objects are typically hidden from the user. -
Design Patterns Design Patterns
Design Patterns CSC207 – Software Design Design Patterns • Design pattern: – A general description of the solution to a well- established problem using an arrangement of classes and objects. • Patterns describe the shape of code rather than the details. – There are lots of them in CSC 301 and 302. Loop patterns from first year • Loop pattern: – A general description of an algorithm for processing items in a collection. • All of you (hopefully) have some loop patterns in your heads. • You don’t really need to think about these any more; you just use them, and you should be able to discuss them with your fellow students. • Some first-year patterns: – Process List – Counted Loop – Accumulator – Sentinel Process list pattern • Purpose: to process every item in a collection where you don’t care about order or context; you don’t need to remember previous items. • Outline: • Example: • Other example: darken every pixel in a picture Counted loop pattern • Purpose: to process a range of indices in a collection. • Outline: • Example: • Other example: print indices of even-length string Accumulator pattern • Purpose: to accumulate information about items in a collection. • Outline: • Example: • Other examples: sum, min, accumulate a list of items meeting a particular criterion. Sentinel pattern • Purpose: to remove a condition in a loop guard. • Outline: • Example: Sentinel pattern, continued • Here is the code that Sentinal replaces; note that i != list.size() is evaluated every time through the loop, even though it is false only once. Design Pattern -
Presentación De Powerpoint
Software Architecture of Oviedoof University Modularity Science Computer of of Course 2018/2019 Jose E. Labra Gayo School Software Software School of Computer Science University of Oviedo Modularity Architecture Software Architecture of Oviedoof University Big Ball of Mud Modular decomposition Definitions Recommendations Modularity styles Layers Aspect Oriented decomposition Domain based decomposition Science Computer of of School Software Architecture Big Ball of Mud of Oviedoof Big Ball of Mud University Described by Foote & Yoder, 1997 Elements Lots of entities intertwined Constraints None Science Computer of of School Software Architecture Big Ball of Mud of Oviedoof Quality attributes (?) University Time-to-market Quick start It is possible to start without defining an architecture Incremental piecemeal methodology Solve problems on demand Cost Cheap solution for short-term projects Science Computer of of School Software Architecture Big Ball of Mud of Oviedoof Problems University High Maintenance costs Low flexibility at some given point At the beginning, it can be very flexible After some time, a change can be dramatic Inertia When the system becomes a Big Ball of Mud it is very difficult to convert it to another thing A few prestigious developers know where to touch Science Clean developers run away from these systems Computer of of School Software Architecture Big Ball of Mud of Oviedoof Some reasons University Throwaway code: You need an immediate fix for a small problem, a quick prototype or proof of concept When it is good -
Five Considerations for Software Developers
FiveFive ConsiderationsConsiderations forfor SoftwareSoftware DevelopersDevelopers Kevlin Henney [email protected] Presented at Jfokus, Stockholm, 30th January 2008. Kevlin Henney [email protected] [email protected] Curbralan Ltd http://www.curbralan.com Voice: +44 117 942 2990 Fax: +44 870 052 2289 Agenda • Introduction • Consideration 1: Economy • Consideration 2: Visibility • Consideration 3: Spacing • Consideration 4: Symmetry • Consideration 5: Emergence • Outroduction 2 What general qualities in a software architecture help to promote its success? We can of course focus on fitness for purpose, cost of change, organisational acceptance, and so on, but are there broad considerations that can be kept in mind when looking at the structural and developmental side of an architecture? Those involved in software have a lot to keep in mind as they negotiate the worlds inside and outside of their code and the relationship between them. For those interested in improving the state of their art there are many (many) sources of specific recommendations they can use to sharpen their practice. This talk takes a step back from the busy, overpopulated and often overwhelming world of such recommendations to focus on five general considerations that can inform more detailed recommendations and specific decisions. Introduction StructuralSoftwareStructural engineering engineering engineering is is theis the the science science science an and dand art art art of of designingof designing designing and and and making, making, making, with with with economyeconomy and and elegance, elegance, buildings,applications, buildings, bridges, bridges, bridges, frameworks, frameworks, frameworks, and and and other other other similar similar similar structuresstructures so so that that they they can can safely safely resist resist the the forces forces to to which which they they may may be be subjected. -
Declare Property Class Accept Null C
Declare Property Class Accept Null C Woesome and nontechnical Joshuah planned inveterately and pull-outs his frontiers sourly and daftly. Unquiet Bernard fly-by very instructively while Rick remains ectotrophic and chastened. Sometimes stereoscopic Addie unnaturalizes her acorns proportionally, but unlidded Cat invert heinously or orientalizes rancorously. Even experts are accepted types and positional parameters and references, and assigns to. Use HasValue property to check has value is assigned to nullable type sometimes not Static Nullable class is a. Thank you declare more freely, declare property class accept null c is useful to provide only one dispiriting aspect of. Here we're defining a suggest that extracts all non-nullable property keys from plant type. By disabling cookies to accept all? The car variable inside counter Person class shouldn't be declared type grass and. Use JSDoc type. Any class property name, null safe code token stream of properties and corresponds to accept a class! Why death concept of properties came into C The decline because not two reasons If the members of a class are private then select another class in C. JavaScript Properties of variables with null or undefined. Type cup type as should pickle the null value variable the pastry of the variable to which null. CS31 Intro to C Structs and Pointers. Using the New Null Conditional Operator in C 6 InformIT. Your extra bet is to get themselves the good group of initializing all variables when you disabled them. This class that null values can declare variables declared inside an exception handling is nullable context switches a varargs in. -
A Project to Model-Driven Development with Naked Objects and Domain-Driven Design
Elihu: A Project to Model-Driven Development with Naked Objects and Domain-Driven Design Samuel Alves Soares1 and Mariela Ines´ Cortes´ 2 1Federal Institute of Education, Science and Technology of Ceara,´ Taua,´ Ceara,´ Brazil 2State University of Ceara,´ Fortaleza, Ceara,´ Brazil Keywords: Model Driven Development, Naked Objects, Domain Driven Design, Domain Patterns, Design Patterns. Abstract: The model-driven development is a approach to creating software through well-defined models containing the information needed to generate the application. However, the software modeling in this approach requires the definition of application infrastructure artifacts in the model, such as user interface technologies and data persistence scheme, in order to transform modeling in final application. This makes the modeling complex, difficult to understand and maintain since new artifacts need to be added, failing to keep the focus on application business domain. To resolve this problem, we propose the Elihu project, a solution based on Naked Objects Pattern, Domain-Driven Design and software design patterns where the developer models just business objects and their characteristics related to the application domain. The full application is generated based on these software patterns and a Naked Objects Pattern framework is responsible for the application infrastructure code and the display of objects to users. The proposed solution benefits the creation of less complex models, that support evolution and modification of requirements along the development and the generation of full applications without manual intervention in the generated code. 1 INTRODUCTION 2006). On the other hand, the ambiguous nature of models and information redundancy along different The focus on the problem domain is pointed views of the same object make it difficult to maintain out as the ideal approach to the development of and make it difficult to adopt the MDD in the industry computer systems (Pawson, 2004). -
Design Patterns
CSE 403: Software Engineering, Winter 2016 courses.cs.washington.edu/courses/cse403/16wi/ Design Patterns Emina Torlak [email protected] Outline • Overview of design patterns • Creational patterns • Structural patterns • Behavioral patterns 2 introoverview of design patterns What is a design pattern? 4 What is a design pattern? • A standard solution to a common programming problem • a design or implementation structure that achieves a particular purpose • a high-level programming idiom 4 What is a design pattern? • A standard solution to a common programming problem • a design or implementation structure that achieves a particular purpose • a high-level programming idiom • A technique for making code more flexible or efficient • reduce coupling among program components • reduce memory overhead 4 What is a design pattern? • A standard solution to a common programming problem • a design or implementation structure that achieves a particular purpose • a high-level programming idiom • A technique for making code more flexible or efficient • reduce coupling among program components • reduce memory overhead • Shorthand for describing program design • a description of connections among program components • the shape of a heap snapshot or object model 4 Why should you care? • You could come up with these solutions on your own … • But you shouldn't have to! • A design pattern is a known solution to a known problem. 5 Types of design patterns • Creational patterns • how objects are instantiated • Structural patterns • how objects / classes can -
Pawson Thesis.Pdf
Naked objects A thesis submitted to the University of Dublin, Trinity College for the degree of Doctor of Philosophy Richard Pawson, Department of Computer Science, Trinity College, Dublin June 2004 1 Foreword by Trygve Reenskaug (Author’s note: Prof. Reenskaug was the external examiner for this thesis. One of the pioneers of object-oriented programming, he is best known as the inventor of the Model- View-Controller pattern. After the thesis was accepted, he generously agreed to write a foreword to the electronically-published version.) The world’s shipbuilding industry went through a heavy modernization program through the nineteen fifties and sixties. My colleague Kjell Kveim invented a control unit for the numerical control of machine tools such as flame cutters. The first unit was installed at the Stord shipyard in 1960 and opened the field for integrated computer aided design and manufacturing. The matching design system, Autokon, was first deployed at the Stord Yard in 1963. Autokon was subsequently adopted by most major shipyards around the world and was still in use by the late nineties. The purpose of Autokon was to empower the ship’s designers. It had a central database holding important information about the shape of the hull, the position of frames and decks, and the shapes of the parts. There was a language that permitted the designers to specify parts in shipbuilding terminology. There was a designer programming facility so that they could specify families of similar parts. Autokon was developed in close collaboration between shipbuilders and scientists. We considered ourselves as tool builders; the success criterion was that the tools should be handy, practicable, serviceable and useful. -
Table of Contents
Table of Contents ± -—T^jTp^om Object-Oriented to Functional Programming 5 Chajava- an introduction 5 java programming paradigms 6 CO imperative programming CD Real-life imperative example Object-oriented paradigm 7 Objects and classes 7 Encapsulation 7 Abstraction 8 Inheritance 8 Polymorphism 9 Declarative programming 10 Functional programming 11 Working with collections versus working with streams 11 An introduction to Unified Modeling Language 12 Class relations 14 Generalization 15 Realization 15 Dependency 16 Association 16 Aggregation 16 Composition 17 Design patterns and principles 17 Single responsibility principle 18 Open/closed principle 20 Liskov Substitution Principle 20 Interface Segregation Principle 22 Dependency inversion principle 23 Summary 24 Chapter 2: Creational Patterns 27 Singleton pattern 27 Synchronized singletons 29 Synchronized singleton with double-checked locking mechanism 30 Lock-free thread-safe singleton 30 tu * y and lazy loacling 31 i he factory pattern 31 Simple factory pattern 32 Table of Contents Static factory 33 Simple factory with class registration using reflection 34 Simple factory with class registration using Product.newlnstance 35 Factory method pattern 36 Anonymous concrete factory 38 Abstract factory 38 Simple factory versus factory method versus abstract factory 40 Builder pattern 40 Car builder example 41 Simplified builder pattern 43 Anonymous builders with method chaining 44 Prototype pattern 45 Shallow clone versus deep clone Object pool pattern Summary аэоэсБ Chapter 3: Behavioral Patterns -
Pharo by Example
Portland State University PDXScholar Computer Science Faculty Publications and Computer Science Presentations 2009 Pharo by Example Andrew P. Black Portland State University, [email protected] Stéphane Ducasse Oscar Nierstrasz University of Berne Damien Pollet University of Lille Damien Cassou See next page for additional authors Let us know how access to this document benefits ouy . Follow this and additional works at: http://pdxscholar.library.pdx.edu/compsci_fac Citation Details Black, Andrew, et al. Pharo by example. 2009. This Book is brought to you for free and open access. It has been accepted for inclusion in Computer Science Faculty Publications and Presentations by an authorized administrator of PDXScholar. For more information, please contact [email protected]. Authors Andrew P. Black, Stéphane Ducasse, Oscar Nierstrasz, Damien Pollet, Damien Cassou, and Marcus Denker This book is available at PDXScholar: http://pdxscholar.library.pdx.edu/compsci_fac/108 Pharo by Example Andrew P. Black Stéphane Ducasse Oscar Nierstrasz Damien Pollet with Damien Cassou and Marcus Denker Version of 2009-10-28 ii This book is available as a free download from http://PharoByExample.org. Copyright © 2007, 2008, 2009 by Andrew P. Black, Stéphane Ducasse, Oscar Nierstrasz and Damien Pollet. The contents of this book are protected under Creative Commons Attribution-ShareAlike 3.0 Unported license. You are free: to Share — to copy, distribute and transmit the work to Remix — to adapt the work Under the following conditions: Attribution. You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).