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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Learning to write DSLs utilities for unit tests and am worried about extensablity

I'm trying to simplify our unit tests with hand written DSL's. So far I have DSL's that walk developers through processing a service after setting up all preconditions and the construction of an ...
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0answers
73 views

Avoiding IllegalStateException in MVP when view is not ready yet

In an effort to improve my coding skills I am trying to make use of the MVP pattern in one of my first Android applications. It is going well but I have hit one issue that I am not sure what is the "...
2
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3answers
362 views

Uses for System.gc() in Java [closed]

In Java, there is a method called System.gc(), which calls the garbage collector (or rather, "suggests" to the JVM to run the GC). Are there valid reasons to call this method? I'm thinking that it ...
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1answer
489 views

Implementation of strategy design pattern

Here is my code: public class StrategyDemo { public static void main(String[] args) { Phone ipPhone = new IPPhone("1234", "ProviderA"); Phone tdmPhone = new TDMPhone(...
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2answers
552 views

Does the pattern of passing in one object instead of many parameters to a constructor have a name?

If you have a constructor that takes a lot of parameters, like this: public OrgUnitsHalRepresentation(List<OrgUnitSummaryHalRepresentation> orgUnitSummaryHalRepresentationList, int count, ...
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1answer
122 views

How to define the motion path of one object on a surface of the other one?

I have an uncommon problem. There are 2 3D objects, which are represented by arrays of vertices and triangles (.stl files). Each of them contains a big enough amount of vertices: 1-10 mln ones. The ...
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4answers
286 views

When copy/pasting private methods is it necessary to carry along the Javadoc? [closed]

So, unfortunately, I'm stuck with code where I'm doing this: @Override method A{ //calls private methods 1-8 } private method 1{ //copy/pasted } And so on for all of the private methods. I'...
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1answer
230 views

Does lots of Instance Variables within my class suggest flawed Design?

Ok so I am setting out to consolidate some learning I have been doing. What I am going to do is create a small game relating to a game I enjoy called Persona. For reference a persona you can think of ...
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1answer
900 views

Which patterns/architecture to apply for “Import Data, Process Data, Export Result”

I was wondering which architecture/patterns to choose for the following problem divided into three steps: Import TestScript Description from File (e.g. .xls, .txt) Process Described TestScript ...
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1answer
259 views

Should I separate a web api from the webserver?

Lets say I'm building a site similar to this or Quora (or some arbitrary blog-like site). I need a real-time component that will be using web-sockets/long-polling to notify the user of new posts, ...
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2answers
279 views

SOAP message testing

I am working in Scala/Java. I'm testing the messaging infrastructure of a part of my system that I did several years ago with CXF and Java. More specifically, I'm re-writing the specification of the ...
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2answers
503 views

Is it necessary to memorize every line of code when it comes to game development? [closed]

I am currently following along a youtube tutorial here and from what I understand we are starting out by creating an engine to run the game. Should I be able to implement all of this by myself without ...
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3answers
492 views

Filtering a List

I will try to simplify my problem. Let say I have a collection (more specifically a List) with different types of elements, for explanation purpose let say we have objects "Person" with different age ...
2
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1answer
96 views

How to allow multiple plugins to provide data for multiple aggregation processes?

I'm working on a Java project in which we want to have data collection plugins that collect data to be processed by one or more data aggregation modules. The plugins will all written in-house. Say for ...
5
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2answers
2k views

docker-izing a classical db-based webapp - single or multiple containers?

I have a classic Java webapp. It is composed of a database (PostgreSQL), a servlet container (Tomcat) and my code (deployed on Tomcat as a *.war file). I want to package/deploy it using Docker (...
2
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2answers
3k views

Do I need to care about 'Thread safety' in java web applications

I have general understanding that what thread safety means , but I don't know much about threads in context of a java webapplication. I am just curious to know that do I need to concern about thread ...
2
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1answer
378 views

Java and rest OOP languages - when to use super or this keywords

I have been programming java for like a year or more, and i have always used the this and super keywords. And yesterday my mate read one source of mine, and told me not to over use it unless you are ...
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5answers
3k views

Should each method have a seperate JUnit test class?

I am writing JUnit unit tests for my classes. Is it better to have a separate class for each method, or have just one test class for every actual class?
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3answers
164 views

How should I approach storing single boolean results for a whole table?

I previously asked this question on stack overflow. But have not received any responses that might help me. So I thought I would try here. http://stackoverflow.com/questions/24883527/best-way-for-me-...
4
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3answers
942 views

What is the best use case for selenium?

I've been trying to develop web applications while at the same time creating the testing. I understand unit testing, I can declare a test method and test specific methods in my application. But I don'...
0
votes
1answer
535 views

In a REST service project, where should we put code that calls a third party REST API?

My project is organized in layers like Configuration Controller Service Repository Domain Our REST Controller is in the Controller layer. We need to connect to another API via REST calls and I'm ...
-1
votes
1answer
338 views

What is design pattern/paradigm for ASP.NET web-apps? [closed]

I don't actually know if my question is correct, but working on a webapp porting from ASP.NET world to Java + Spring platform I came up with this question in mind. Using Spring MVC, the new version ...
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3answers
412 views

Trying to understand how MySQL license applies to code I wrote

I have an ERP, coded with Java and the database in MYSQL Community edition. When I was going to sell it to a client he asked me for the sources to my application (with the belief that it is GPLed). I ...
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3answers
343 views

Passing data between hundreds of objects in java [closed]

Currently, I'm working with a group on building a model. This model simulates interactions between many "agents" in a region. Agents can be any entity such as a city, a farmer, a business etc. Each ...
5
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2answers
2k views

Why to declare a String (as final) and then use it?

In a typical spring mvc validator class, while inserting an errorCode value in the Errors object, what difference does it make between using a String (props.somefield.req) like so errors.rejectValue("...
2
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3answers
308 views

Duck typing in statically-typed languages

Is it a fair assumption to say that an overloaded constructor for a class can be thought of as a 'duck' for duck typing? Let's say that ClassA has an overloaded constructor, it would stand to reason ...
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2answers
3k views

Is “continue” and “break” in loops antipattern/bad practice in Java? [duplicate]

I see the main purpose of continue in programming, it can get you out from the rest of loop steps like: while(condition1){ ... code ... if(!condition2){ continue; } ... code ... if(...
2
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1answer
639 views

Several enum classes that declare constants with the same names

I'm working on a Java library for sorts for Magic: the Gathering. Well, without going into a lot of detail, in the game there are five different colors of magic: white, blue, black, red, and green. ...
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1answer
193 views

Web-services REST security clarification

I'm newbie of web services programming and I have some problem to understand how to work authentication/security for REST WS pattern. I had read about OAuth but I haven't understand how it work in ...
15
votes
12answers
3k views

Why use getters only as opposed to marking things final? [duplicate]

I'm working in a java role after working a couple years in functional programming. Our company was bought by google and I took a java role after the acquisition. Coming back to java as a polyglot ...
5
votes
2answers
364 views

What's the easiest way to comply with open source licenses? [closed]

I'm really confused by all the open source licensing details like "I wrote a web application, which should run on a computer not owned by me. My software uses the library/language xxx. Is this ...
34
votes
2answers
5k views

Do modern languages still use parser generators?

I was researching about the gcc compiler suite on wikipedia here, when this came up: GCC started out using LALR parsers generated with Bison, but gradually switched to hand-written recursive-...
0
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1answer
100 views

Confusion about instance in an interface

I'm trying to learn OGSi framework (Equinox distribution). I have registered my service, but I'm confused about a piece of code that I've copied: IAgendaService service = new AgendaService(); What ...
3
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2answers
3k views

What happens if I close an InputStream that is passed as an argument?

I have read that Java is pass-by-value, and I've been reading about it in this question at StackOverflow, but I'm still a bit confused, regarding the close() or shutdown() methods in various classes. ...
0
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1answer
860 views

Differences between Direct, Composition, Aggregation, and Temporary Association

I am looking to take my java certification very soon, and I have a question about the different types of associations described in the official oracle guide book. The book describes the 4 as the ...
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votes
4answers
517 views

Why can you have statefulness inside a static class in java?

I was playing around with Java today and I read about static inner classes. Why can you have 'statefulness' inside of a static inner class. For instance: class outerClass { static class ...
0
votes
3answers
5k views

Nested maps vs. combined keys

in the project I am currently working on we had three different types of prices depending on the age of the user (adult, child, etc...). So we had on the DB a table looking like this: PRICES type ...
0
votes
1answer
134 views

Huge long addition overhead compared to Native call?

A run a simple test JDK 1.7.0_45 (Windows 7, 64bit): Test 1: long start = System.nanoTime(); for (int i=0; i < 1000000; i++) { System.currentTimeMillis(); } elapsed = System.nanoTime() - ...
4
votes
1answer
383 views

If a dependency is not in the maven repository should I add it to source control?

One of the jar files that I use in my code is not in the maven repository(and yes I tried to avoid using it). I have installed it locally so when I build the project it gets picked up by maven. I also ...
3
votes
1answer
3k views

Builder pattern inside interface. Bad design decision?

I am having trouble evaluating an implementation of the builder pattern I just came up with. The context is an API library, so I am trying not to expose any implementations in order to have a stable ...
0
votes
1answer
435 views

Interactive session with a command line program using Java?

I plan to write a website frontend for a free computer algebra system (Reduce, http://reduce-algebra.com/). On the webserver I have a Java virtual machine running, and Reduce is also installed. I can ...
41
votes
9answers
4k views

Programming for future use of interfaces

I have a colleague sitting next to me who designed an interface like this: public interface IEventGetter { public List<FooType> getFooList(String fooName, Date start, Date end) ...
0
votes
1answer
187 views

Why does this method return 2 values if I only ask for one and there is no sort of conditional statement anywhere?

I'm writing this very simple program from this one PDF called Think AP Java, and I can't seem to wrap my head around this: When I write public static double method_1(double x) { double ...
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votes
1answer
990 views

How Jetbrain Phpstorm IDE is working without installed java? [closed]

As far as I know Jetbrains PHPStorm is programmed in Java but while I don't have Java installed in my Windows 7 PC, PHPstorm is installed and working without any problem. How It's done?
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2answers
865 views

how to approach pharmacy software project [closed]

I would like to complete a pharmacy software proof concept. But I have a few questions I do not know. Physician information In order to refill or dispense a new RX the software needs to have access ...
0
votes
2answers
3k views

Way for java program to read file from when it was stopped

I am working on an application that reads a log file, looks for a specific string, sends alert emails and saves data from the file into a database. The reading functionality is working well, but I am ...
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votes
1answer
181 views

How can I perform a logical test to ensure that MY CUSTOM ERROR gets thrown instead of the NumberFormatException? [closed]

I am working on something that should be fairly simple. I have 95% of my program working, but one piece is still not fulfilling the requirement. (FYI, this is for a homework assignment, but I will ...
3
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2answers
167 views

Program Design clearness vs convenience

I've recently disputed with my colleague about the following situation: I've developed a framework that processes the resources (in java, although its not really important). It goes (simplified, ...
4
votes
3answers
192 views

Returning results of method on batch list?

The title is a bit vague so I'll try to elaborate. I have a function makeFoo(int bar) -> returns Foo or throws Exception. I also have a batch version of this makeFoos(int[] bars) -> ...
0
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3answers
289 views

When to use default access modifier?

I want to understand, from design point of view, in what situations I should use default access modifier, and when I shouldn't. I found this related question, that provides some basic explanations, ...