A methodology that enables a system to be modeled as a set of objects that can be controlled and manipulated in a modular manner

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18
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What is the principle of least astonishment?

In programming what is called Principle of Least Astonishment? How is this concept related to designing good APIs? Is this something applicable to only object oriented programming or does it permeate ...
10
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4answers
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How does thinking on design patterns and OOP practices change in dynamic and weakly-typed languages?

There is a fairly helpful question already along these lines ("Non-OOP Design Patterns?"), but I am more curious about a transitional point of view for someone just getting started with dynamic and ...
28
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12answers
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Why should a class be anything other than “abstract” or “final/sealed”?

After 10+ years of java/c# programming, I find myself creating either: abstract classes: contract not meant to be instantiated as-is. final/sealed classes: implementation not meant to serve as base ...
25
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13answers
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Why are objects passed by reference?

A young co-worker who was studying OO has asked me why every object is passed by reference, which is the opposite of primitive types or structs. It is a common characteristic of languages such as Java ...
16
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5answers
1k views

Is SRP (Single Responsibility Principle) objective?

Consider two UI designers who want to design "user attractive" designs. "User attraction" is a concept that is not objective and only resides in the mind of designers. Thus designer A could for ...
9
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4answers
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What's the difference between overloading a method and overriding it in Java?

What's the difference between overloading a method and overriding it in Java? Is there a difference in method signature, access specifier, return type, etc.?
28
votes
3answers
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Which is a better practice - helper methods as instance or static?

This question is subjective but I was just curious how most programmers approach this. The sample below is in pseudo-C# but this should apply to Java, C++, and other OOP languages as well. Anyway, ...
6
votes
3answers
6k views

When is method overloading appropriate?

Suppose I am working on an existing, reasonably large system. I have an object, myObject of class MyClass (for the example's sake, suppose I'm working in Java). myObject is a composition containing a ...
5
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4answers
2k views

Why are public and private accessors considered good practice? [duplicate]

Possible Duplicate: When are Getters and Setters Justified Why exactly is having public and private accessors like these: private string foo; public string Foo { get { return ...
4
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2answers
487 views

Designing a library that is easy to use: composition or inheritance

I have designed a small library for work that consists of a few exposed classes. These can basically be thought of as a server class and client class. But now that I am writing all the test cases and ...
3
votes
4answers
974 views

Explanation of the definition of interface inheritance as described in GoF book

I am reading the first chapter of the Gof book. Section 1.6 discusses about class vs interface inheritance: Class versus Interface Inheritance It's important to understand the difference between ...
2
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2answers
4k views

Object oriented immutability: final classes or final methods

One of the things you see in numerous places in the standard java library is final classes. It is claimed that this is for immutability which I understand...to an extent. Suppose you have a class: ...
8
votes
1answer
7k views

Why is imperative programming preferred over functional programming? [closed]

Background: I am proponent of functional programming who works at a VB.NET shop where the prevailing mental model is imperative programming. Being that foundation of our system is WinForms I can ...
0
votes
4answers
3k views

Is there really Object-relational impedance mismatch?

It is always stated that it is hard to store applications objects in relational databases - the object-relational impedance mismatch - and that is why Document databases are better. However, is there ...
86
votes
22answers
9k views

Is OOP hard because it is not natural?

One can often hear that OOP naturally corresponds to the way people think about the world. But I would strongly disagree with this statement: We (or at least I) conceptualize the world in terms of ...
39
votes
2answers
6k views

What did Alan Kay mean by “assignment” in The Early History of Smalltalk?

I have been reading The Early History of Smalltalk and there are a few mentions of "assignment" which make me question my understanding of its meaning: Though OOP came from many motivations, two ...
35
votes
2answers
7k views

Does the ActiveRecord pattern follow/encourage the SOLID design principles?

I'm interested in whether ActiveRecord pattern, made famous from Ruby on Rails, encourages or discourages the use of SOLID design principles. For example, it seems to me that ActiveRecord objects ...
40
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8answers
9k views

What should be allowed inside getters and setters?

I got into an interesting internet argument about getter and setter methods and encapsulation. Someone said that all they should do is an assignment (setters) or a variable access (getters) to keep ...
24
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5answers
4k views

How to make the transition to functional programming?

Lately, I have been very intrigued with F# which I have been working a bit with. Coming mostly from Java and C#, I like how concise and easily understandable it is. However, I believe that my ...
31
votes
4answers
7k views

What exactly is procedural programming? How exactly is it different from OOP? Is it the same as functional programming?

I am programming in Java in a very object-oriented (OO) style. OOP comes very intuitively to me, but I have very little knowledge about other kinds of programming. What exactly is procedural ...
22
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10answers
30k views

Why use an interface when the class can directly implement the functions? [duplicate]

Possible Duplicate: Why are interfaces useful? Like most faculty, my java faculty introduced interface without explaining or even mentioning its practical use. Now I imagine interfaces have a ...
34
votes
3answers
3k views

Why is an anemic domain model considered bad in C#/OOP, but very important in F#/FP?

In a blog post on F# for fun and profit, it says: In a functional design, it is very important to separate behavior from data. The data types are simple and "dumb". And then separately, you ...
20
votes
5answers
6k views

Is objected oriented programming paradigm outdated since it is anti-modular and anti-parallel? [closed]

I have read the controversial article Teaching FP to freshmen posted by Robert Harper who is a professor in CMU. He claimed that CMU would no longer teach object oriented programming in the ...
38
votes
6answers
5k views

How to think as a C programmer after biased with OOP language? [closed]

Previously, I've only used Object Oriented Programming languages (C++, Ruby, Python, PHP), and am now learning C. I'm finding it difficult to figure out the proper way to do things in a language with ...
20
votes
1answer
5k views

What did they call Object-Oriented Programming before Alan Kay invented the term?

Alan Kay claims that "I made up the term "object-oriented", and I can tell you I did not have C++ in mind." What he had in mind, of course, was Smalltalk. But he did not make up object-oriented ...
46
votes
10answers
6k views

Should we avoid custom objects as parameters?

Suppose I have a custom object, Student: public class Student{ public int _id; public String name; public int age; public float score; } And a class, Window, that is used to show ...
26
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6answers
4k views

Does learning a functional language make a better OOP programmer? [closed]

As a Java/C#/C++ programmer I hear a lot of talk about functional languages, but have never found a need to learn one. I've also heard that the higher level of thinking introduced in functional ...
26
votes
12answers
2k views

How large is ok for a Class?

I’m a long time developer (I’m 49) but rather new to object oriented development. I’ve been reading about OO since Bertrand Meyer’s Eiffel, but have done really little OO programming. The point is ...
19
votes
11answers
3k views

is OOP the dominant programming model in real world?

Objects Never? Well, Hardly Ever In the VIEWPOINT section of Communications of The ACM, I found an interesting article entitled "Objects Never? Well, Hardly Ever". It’s a radically different ...
14
votes
4answers
3k views

How does the Law of Demeter apply to object-oriented systems regarding coupling and cohesion? [closed]

How does the Law of Demeter applied to object-oriented systems with coupling and cohesion? I was reading a book "Software development and professional practice" and came across the chapter about LoD, ...
32
votes
7answers
4k views

Complete immutability and Object Oriented Programming

In most OOP languages, objects are generally mutable with a limited set of exceptions (like e.g. tuples and strings in python). In most functional languages, data is immutable. Both mutable and ...
13
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1answer
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How to verify the Liskov substitution principle in an inheritance hierarchy?

Inspired by this answer: Liskov Substitution Principle requires that Preconditions cannot be strengthened in a subtype. Postconditions cannot be weakened in a subtype. Invariants ...
28
votes
8answers
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Is splitting up a function into several inner functions an anti-pattern? [duplicate]

Imagine a long and complicated process, which is started by calling function foo(). There are several consecutive steps in this process, each of them depending on result of the previous step. The ...
20
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4answers
5k views

Clarify the Open/Close Principle

As I have had it explained, the open/close principle states that once written code should not be modified (aside from bug fixes). But if my business rules change shouldn't I modify the code ...
17
votes
4answers
1k views

Empty interface to combine multiple interfaces

Suppose you have two interfaces: interface Readable { public void read(); } interface Writable { public void write(); } In some cases the implementing objects can only support one of these ...
10
votes
7answers
2k views

OOP principles and method names

class Boxer: def punch(self, punching_bag, strength): punching_bag.punch(strength) class PunchingBag: def punch(self, strength): print "Punching bag punched with strength", ...
13
votes
3answers
1k views

Pure virtual or abstract, what's in a name?

While discussing a question about virtual functions on Stack Overflow, I wondered whether there was any official naming for pure (abstract) and non-pure virtual functions. I always relied on ...
12
votes
3answers
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Dependency Inversion Principle: How to define “high-level policy” and “low-level detail” to other people?

I am trying to explain the dependency inversion principle to my (mostly junior) colleagues. How can we define which one is the "high-level policy" and which one is the "low-level detail" in a software?...
7
votes
6answers
5k views

How to avoid downcasting?

My question is about a special case of the super class Animal. My Animal can moveForward() and eat(). Seal extends Animal. Dog extends Animal. And there's a special creature that also extends ...
4
votes
2answers
1k views

How does MVC work with the principle “Tell, Don't ask”?

Procedural code gets information then makes decisions. Object-oriented code tells objects to do things. — Alec Sharp So, when a view wants to display some information that is suppose to be ...
2
votes
4answers
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Why 'List<E>' is an 'interface' but not 'abstract class'?

Amidst defining the hierarchy, firstly, one can think to embed the abstract method(behavior) in abstract class only because the derive concrete class possess that behavior as core behavior with it's ...
17
votes
7answers
2k views

To rewrite or slowly refactor old C++ project [duplicate]

Our team has recently inherited a relatively large project from another company (~250k lines). It was developed using C++Builder and we intend to port the Ui side to Qt. Most of the Ui code is ...
13
votes
8answers
2k views

Mental Models or Real-World-Metaphors for Functional Programming

Does anyone have a good mental model or metaphor for functional programming which references something in the real world? Object Oriented programing intuitively makes sense to me. There are things ...
7
votes
3answers
1k views

Unit testing time-bound code

I'm currently working on an application that does a lot of time-bound operations. That is, based on long now = System.currentTimeMillis();, and combined with an scheduler, it will calculate periods of ...
6
votes
6answers
8k views

Is there any difference between interfaces and abstract classes that have abstract methods only?

Let's say we have an abstract class and let this class has only abstract methods. Is this abstract class different from an interface that has same methods only? What I am looking to know is if there ...
6
votes
5answers
1k views

Should I always encapsulate an internal data structure entirely?

Please consider this class: class ClassA{ private Thing[] things; // stores data // stuff omitted public Thing[] getThings(){ return things; } } This class exposes the ...
5
votes
6answers
6k views

What are abstract classes and abstract methods?

I got several explanations but so far I'm not able to understand that what are the abstract classes and methods in Java. Some said it has to do something with the security of the program, other said ...
4
votes
5answers
3k views

Why is Encapsulation considered a primary principle in OOP?

I am currently trying to understand more deeply the 4 principles of OOP: Abstraction, Encapsulation, Inheritance, and Polymorphism. After studying the four principles, I don't fully understand why ...
4
votes
3answers
3k views

How to use multiple programming languages together in the same program? [closed]

Such a simple question, but I have not found a reasonable answer to this. I currently program in Python, an interpreted language. I always hear of people using multiple languages in the same program? ...
3
votes
4answers
3k views

PHP, structural or OOP based language? [closed]

I would like to discuss why is PHP called a structural language? what are the OO concepts that cannot be implemented using PHP?