Java is a high-level, platform-independent, object-oriented programming language originally developed by Sun Microsystems. Java is currently owned by Oracle, which purchased Sun in 2010.

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349
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Why isn't Java used for modern web application development? [closed]

As a professional Java programmer, I've been trying to understand - why the hate toward Java for modern web applications? I've noticed a trend that out of modern day web startups, a relatively small ...
169
votes
13answers
49k views

Should we avoid object creation in Java?

I was told by a colleague that in Java object creation is the most expensive operation you could perform. So I can only conclude to create as few objects as possible. This seems somewhat to defeat ...
160
votes
10answers
21k views

Mono is frequently used to say “Yes, .NET is cross-platform”. How valid is that claim? [closed]

In What would you choose for your project between .NET and Java at this point in time? I say that I would consider the "Will you always deploy to Windows?" the single most important technical decision ...
152
votes
7answers
155k views

What does the Spring framework do? Should I use it? Why or why not?

So, I'm starting a brand-new project in Java, and am considering using Spring. Why am I considering Spring? Because lots of people tell me I should use Spring! Seriously, any time I've tried to get ...
128
votes
5answers
50k views

Choosing between Single or multiple projects in a git repository?

In a git environment, where we have modularized most projects, we're facing the one project per repository or multiple projects per repository design issue. Let's consider a modularized project: ...
127
votes
5answers
24k views

What exactly makes the Haskell type system so revered (vs say, Java)?

I'm starting to learn Haskell. I'm very new to it, and I am just reading through a couple of the online books to get my head around its basic constructs. One of the 'memes' that people familiar with ...
122
votes
16answers
77k views

When are Getters and Setters Justified

Getters and setters are often criticized as being not proper OO. On the other hand most OO code I've seen has extensive getters and setters. When are getters and setters justified? Do you try to ...
110
votes
10answers
86k views

How do you unit test private methods?

I am working on a java project. I am new to unit testing. What is the best way to unit test private methods in java classes?
103
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15answers
20k views

Why did memory-managed languages like Java, Javascript, and C# retain the `new` keyword?

The new keyword in languages like Java, Javascript, and C# creates a new instance of a class. This syntax seems to have been inherited from C++, where new is used specifically to allocate a new ...
100
votes
11answers
33k views

What backs up the claim that C++ can be faster than a JVM or CLR with JIT? [closed]

A reoccurring theme on SE I've noticed in many questions is the ongoing argument that C++ is faster and/or more efficient than higher level languages like Java. The counter-argument is that modern JVM ...
95
votes
13answers
15k views

Should we avoid language features that C++ has but Java doesn't to increase maintainability?

Suppose I am limited to use C++ by the environment in the project. Is it good to prevent the use of some language features that C++ has but Java doesn't have (e.g.: multiple inheritance, operator ...
85
votes
18answers
15k views

Is it poor programming practice to pass parameters as Objects? [duplicate]

So, we've got a guy who likes to write methods that take Objects as parameters, so they can be 'very flexible.' Then, internally, he either does direct casting, reflection or method overloading to ...
85
votes
9answers
19k views

Why is it hard to make a Java program 'appear native'?

Most Java applications don't look the same as C/C++ applications. Swing might have been designed on purpose to have a distincitve look, but based on what I've read, SWT for example tried to 'look ...
81
votes
16answers
13k views

Do the young minds need to learn the pointer concepts?

Why did the C master Dennis Ritchie introduce pointers in C? And why did the other programming languages like VB.NET or Java or C# eliminate them? I have found some points in Google, and I want to ...
80
votes
5answers
22k views

Why doesn't Java 8 include immutable collections?

The Java team has done a ton of great work removing barriers to functional programming in Java 8. In particular, the changes to the java.util Collections do a great job of chaining transformations ...
76
votes
4answers
43k views

How is a Java reference different from a C pointer?

C has pointers and Java has what is called references. They have some things in common in the sense that they all point to something. I know that pointers in C store the addresses they point to. Do ...
75
votes
6answers
12k views

Why are floats still part of the Java language when doubles are mostly recommended instead?

In every place I've looked, it says that double is superior to float in almost every way. float has been made obsolete by double in Java, so why is it still used? I program a lot with Libgdx, and ...
70
votes
15answers
19k views

Why would it ever be possible for Java to be faster than C++?

Sometimes Java outperforms C++ in benchmarks. Of course, sometimes C++ outperforms. See the following links: http://keithlea.com/javabench/ ...
69
votes
17answers
8k views

Is imposing the same code format for all developers a good idea?

We are considering to impose a single standard code format in our project (auto format with save actions in Eclipse). The reason is that currently there is a big difference in the code formats used by ...
68
votes
11answers
5k views

Never use Strings in Java? [closed]

I stumbled upon a blog entry discouraging the use of Strings in Java for making your code lack semantics, suggesting that you should use thin wrapper classes instead. This is the before and after ...
67
votes
12answers
8k views

I've been told that Exceptions should only be used in exceptional cases. How do I know if my case is exceptional?

My specific case here is that the user can pass in a string into the application, the application parses it and assigns it to structured objects. Sometimes the user may type in something invalid. ...
67
votes
1answer
9k views

What's the difference between Scala and Red Hat's Ceylon language? [closed]

Red Hat's Ceylon language has some interesting improvements over Java: The overall vision: learn from Java's mistakes, keep the good, ditch the bad The focus on readability and ease of learning/use ...
66
votes
16answers
7k views

How much freedom should a programmer have in choosing a language and framework?

I started working at a company that is primarily C# oriented. We have a few people who like Java and JRuby, but a majority of programmers here like C#. I was hired because I have a lot of experience ...
65
votes
13answers
85k views

Why isn't Java more widely used for game development? [closed]

I'm not a game developer or anything, but I know that Java is not very widely used for game development. Java should be fast enough for most games, so where's the catch? I can think of some reasons: ...
64
votes
9answers
15k views

How do you avoid getters and setters?

I'm having something of a hard time with designing classes in an oo way. I've read that objects expose their behavior, not their data; therefore, rather than using getter/setters to modify data, the ...
64
votes
5answers
9k views

Is Haskell's type system formally equivalent to Java's? [closed]

I realize some things are easier/harder in one language than the other, but I'm only interested in type-related features that are possible in one and impossible/irrelevant in the other. To make it ...
62
votes
11answers
8k views

Did the developers of Java consciously abandon RAII?

As a long-time C# programmer, I have recently come to learn more about the advantages of Resource Acquisition Is Initialization (RAII). In particular, I have discovered that the C# idiom: using (var ...
61
votes
21answers
34k views

“Don't do programming after a few years of starting career”. Is this a fair advice? [closed]

I am a little experienced developer having approximately 5 years experience in PHP and somewhat less in Java, C# and trying to learn some Python nowadays. Since the start of my career as a programmer ...
61
votes
11answers
24k views

Why is String immutable in Java?

I couldn't understand the reason of it. I always use String class like other developers, but when I modify the value of it, new instance of String created. What might be the reason of immutability ...
61
votes
7answers
64k views

Why use try … finally without a catch clause?

The classical way to program is with try ... catch. When is it appropriate to use try without catch? In Python the following appears legal and can make sense: try: #do work finally: #do ...
61
votes
5answers
102k views

Stack and Heap memory in Java

As I understand, in Java, stack memory holds primitives and method invocations and heap memory is used to store objects. Suppose I have a class class A { int a ; String b; ...
60
votes
4answers
5k views

Why were Java collections implemented with “optional methods” in the interface?

During my first implementation extending the Java collection framework, I was quite surprised to see that the collection interface contains methods declared as optional. The implementer is expected ...
58
votes
1answer
13k views

What are these different Java versions for?

I am just about to start my Java journey, ( I've already dabbled in C++) but I am getting really confused about all the different versions of Java: JavaSE JavaEE JavaFX etc. Can someone explain ...
56
votes
9answers
20k views

Why should I use a factory class instead of direct object construction?

I have seen the history of several С# and Java class library projects on GitHub and CodePlex, and I see a trend of switching to factory classes as opposed to direct object instantiation. Why should I ...
55
votes
4answers
6k views

Is functional programming faster in multithreading because I write things differently or because things are compiled differently?

I'm diving into the world of functional programming and I keep reading everywhere that functional languages are better for multithreading/multicore programs. I understand how functional languages do a ...
55
votes
7answers
26k views

Excessive use “final” keyword in Java [duplicate]

While I understand what the final keyword is used for in the context of classes and methods as well as the intent of its use for in regards to variables; however, the project I just started working on ...
53
votes
6answers
8k views

Should a getter throw an exception if its object has invalid state?

I often run into this problem, especially in Java, even if I think it's a general OOP issue. That is: raising an exception reveals a design problem. Suppose that I have a class that has a String name ...
53
votes
6answers
20k views

What is the point of having every service class have an interface? [duplicate]

At the company I work at, every service class has a corresponding interface. Is this necessarily? Most of these interfaces are only used by a single class and we are not creating any sort of public ...
53
votes
7answers
83k views

Why declare final variables inside methods? [duplicate]

Studying some classes of Android, I realized that most of the variables of methods are declared as final. Example code taken from the class android.widget.ListView: /** * @return Whether the list ...
52
votes
10answers
3k views

Is it wise to ask about design decisions made on a product during an interview? [closed]

I've been thinking about interview questions lately and I've been reflecting on bad interview experiences I've had in the past. One of particular note is where I had asked the interviewer why the team ...
52
votes
5answers
20k views

In Java, should I use “final” for parameters and locals even when I don't have to?

Java allows marking variables (fields / locals / parameters) as final, to prevent re-assigning into them. I find it very useful with fields, as it helps me quickly see whether some attributes - or an ...
51
votes
10answers
16k views

Is better Show() + Hide() or SetVisible(bool visible)?

What is better and why? (From interface-design point of view) : a) To have two Show() and Hide() functions b) To have one SetVisible(bool visible) function EDIT: For example some object have ...
51
votes
4answers
27k views

Is it better to use assert or IllegalArgumentException for required method parameters?

In Java, which is more highly recommended, and why? Both types will throw exceptions, so in that regard handling them is the same. assert is slightly shorter, but I'm not sure how much that matters. ...
50
votes
11answers
21k views

Why is it good to split a program into multiple classes? [closed]

I'm still a student in high school (entering 10th grade), and I have yet to take an actual computer course in school. Everything I've done so far is through books. Those books have taught me concepts ...
50
votes
4answers
59k views

Reasons NOT to use JSF [closed]

I am new to StackExchange, but I figured you would be able to help me. We're crating a new Java Enterprise application, replacing an legacy JSP solution. Due to many many changes, the UI and parts of ...
49
votes
2answers
28k views

When not to use Google Web Toolkit? [closed]

I'm considering use of GWT on a major in-house web app development project, namely it's major advantage in my eyes is the cross-compilation to Javascript which would (at least theoretically) help my ...
49
votes
11answers
4k views

I don't understand how TDD helps me get a good design if I need a design to start testing it

I'm trying to wrap my head around TDD, specifically the development part. I've looked at some books, but the ones I found mainly tackle the testing part - the History of NUnit, why testing is good, ...
48
votes
10answers
3k views

When does “proper” programming no longer matter?

I've been building an android game in my spare time. It's using the libgdx library so quite a bit of the heavy lifting is done for me. While developing, I carelessly selected datatypes for some ...
46
votes
8answers
6k views

Why a static main method in Java and C#, rather than a constructor?

I’m Looking for a definitive answer from a primary or secondary source for why (notably) Java and C# decided to have a static method as their entry point, rather than representing an application ...
46
votes
7answers
10k views

How to deal with static utility classes when designing for testability

We are trying to design our system to be testable and in most parts developed using TDD. Currently we are trying to solve the following problem: In various places it is necessary for us to use static ...