Search Results

Search found 720 results on 29 pages for 'conventions'.

Page 10/29 | < Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >

  • Patterns: Local Singleton vs. Global Singleton?

    - by Mike Rosenblum
    There is a pattern that I use from time to time, but I'm not quite sure what it is called. I was hoping that the SO community could help me out. The pattern is pretty simple, and consists of two parts: A singleton factory, which creates objects based on the arguments passed to the factory method. Objects created by the factory. So far this is just a standard "singleton" pattern or "factory pattern". The issue that I'm asking about, however, is that the singleton factory in this case maintains a set of references to every object that it ever creates, held within a dictionary. These references can sometimes be strong references and sometimes weak references, but it can always reference any object that it has ever created. When receiving a request for a "new" object, the factory first searches the dictionary to see if an object with the required arguments already exits. If it does, it returns that object, if not, it returns a new object and also stores a reference to the new object within the dictionary. This pattern prevents having duplicative objects representing the same underlying "thing". This is useful where the created objects are relatively expensive. It can also be useful where these objects perform event handling or messaging - having one object per item being represented can prevent multiple messages/events for a single underlying source. There are probably other reasons to use this pattern, but this is where I've found this useful. My question is: what to call this? In a sense, each object is a singleton, at least with respect to the data it contains. Each is unique. But there are multiple instances of this class, however, so it's not at all a true singleton. In my own personal terminology, I tend to call the factory method a "global singleton". I then call the created objects "local singletons". I sometimes also say that the created objects have "reference equality", meaning that if two variables reference the same data (the same underlying item) then the reference they each hold must be to the same exact object, hence "reference equality". But these are my own invented terms, and I am not sure that they are good ones. Is there standard terminology for this concept? And if not, could some naming suggestions be made? Thanks in advance...

    Read the article

  • Is it good practice to name variables differently when defining more than one function?

    - by John
    For example, in this simple function where fun1 takes as input two numbers, adds them together and passes them to function 2 for printing the output. var1_in is local to each function, so is it OK to use the name var1_in in both functions, or is it better practice to call them different things? fun1 <- function (var1_in, var2_in) { var3 = var1_in + var2_in fun2(var3) } fun2 <- function (var1_in) { var4 = var1_in print(var4) }

    Read the article

  • Strange Java Coding??? Class in class???

    - by poeschlorn
    Hi guys, I got a question about Java coding in general... In some sample codes there are methods and classes declared WITHIN other methods and/or classes.... I've never heard/red about this...what effect does this kind of programming have? Wouldn't it be better to write down classes in a seperate file and methods side by side and not within each other (like every book tells you)? What are the advantages and disadvantages of this kind of programming? Here's an example of what I mean: Handler mHandler = new Handler() { public void handleMessage(android.os.Message msg) { TextView textView = (TextView) findViewById(R.id.description); textView.setText(mRoad.mName + " " + mRoad.mDescription); MapOverlay mapOverlay = new MapOverlay(mRoad, mapView); List<Overlay> listOfOverlays = mapView.getOverlays(); listOfOverlays.clear(); listOfOverlays.add(mapOverlay); mapView.invalidate(); }; };

    Read the article

  • Why do I get a "warning: no newline at end of file" ?

    - by user198729
    The file is a helloworld.cpp: #include <iostream> using namespace std; int main() { if(true) cout << "!!!Hello World!!!" << endl; // prints !!!Hello World!!! return 0; } But when I build it,get a warning: g++ -Wall -O2 -c -o hw.o hw.cpp hw.cpp:8:2: warning: no newline at end of file g++ -o myprog hw.o If I add a newline at the end,the warning will go. Why is that newline at end of file recommended in a cpp source file?

    Read the article

  • Which namespace does operator<< (stream) go to?

    - by aaa
    If I have have some overloaded ostream operators, defined for library local objects, is its okay for them to go to std namespace? If I do not declare them in std namespace, then I must use using ns:: operator <<. As a possible follow-up question, are there any operators which should go to standard or global namespace?

    Read the article

  • Is there a convention for organizing the include/exports in a large C++ project ?

    - by BlueTrin
    Hello, In a large C++ solution, is there a best/standard way to separate the include files necessary to build an intermediary DLL and the include files which will be used by the DLL clients ? We have grouped all the include files in a folder called Interface (for DLL interface), but there the customers have to either include the Interface folder as a default include folder or type the full name as: #include "ProjectName/Interface/myinterface.h" Wouldn't it be better to create a separate folder called exports where I would create a folder called ProjectName and put the include files there ? So that the customers would be typing: #include "ProjectName/myinterface.h" If I do the thing right above, then should I keep the files within the solution and produce a post build event (I use Visual Studio 2k5) to copy the files into the "export" folder (/ProjectName/) ? Or is it better to just include directly the files from this folder within my project (this is more direct and has less chances to cause maintenance issues ? I am more looking for advice than for a definite solution. Thank you for reading this ! Anthony

    Read the article

  • domain modeling naming problem

    - by cherouvim
    Hello There are some simple entities in an application (e.g containing only id and title) which rarely change and are being referenced by the more complex entities of the application. These are usually entities such as Country, City, Language etc. How are these called? I've used the following names for those in the past but I'm not sure which is the best way to call them: reference data lookup values dictionaries thanks

    Read the article

  • How to extract messages to translate from a Play! application

    - by Martin
    I'm writing my first application using the Play! framework and I was wondering if there was a tool that could extract the messages that need translation from my views and controllers for me ? It is rather cumbersome to fill the conf/messages(.xx) file while I'm developing my app, but I'm afraid that if I don't do it as I go, I will never be able to completely translate my application afterwards. Such tools exist with other framework such as CakePHP for instance, and I think that it shouldn't be hard to write one by myself, but if there already is one... I was also wondering, what should I name the keys of the messages in my application ? Using gettext, it's not bad practice to directly type in the message in english as the key, but is it with the system that Play! uses (MessageFormat, right ?) ? Does anyone have an advice or naming convention (something like controller.action.describe_the_message maybe) ? Thank you for your advices !

    Read the article

  • Most awkward/misleading method in Java Base API ?

    - by JG
    I was recently trying to convert a string literal into a boolean, when the method "boolean Boolean.getBoolean(String name)" popped out of the auto-complete window. There was also another method ("boolean Boolean.parseBoolean(String s)") appearing right after, which lead me to search to find out what were the differences between these two, as they both seemed to do the same. It turns out that what Boolean.getBoolean(String name) really does is to check if there exists a System property (!) of the given name and if its value is true. I think this is very misleading, as I'm definitely not expecting that a method of Boolean is actually making a call to System.getProperty, and just by looking at the method signature, it sure looks (at least to me) like it should be used to parse a String as a boolean. Sure, the javadoc states it clearly, but I still think the method has a misleading name and is not in the right place. Other primitive type wrappers, such as Integer also have a similar method. Also, it doesn't seem to be a very useful method to belong in the base API, as I think it's not very common to have something like -Darg=true. Maybe it's a good question for a Java position interview: "What is the output of Boolean.getBoolean("true")?". I believe a more appropriate place for those methods would be in the System class, e.g., getPropertyAsBoolean; but again, I still think it's unnecessary to have these methods in the base API. It'd make sense to have these in something like the Properties class, where it's very common to do this kind of type conversions. What do you think of all this ? Also, if there's another "awkward" method that you're aware of, please post it. N.B. I know I can use Boolean.valueOf or Boolean.parseBoolean to convert a string literal into a boolean, but I'm just looking to discuss the API design.

    Read the article

  • Table Naming Dilemma: Singular vs. Plural Names

    - by ProfK
    Convention has it that table names should be the singular of the entity that they store attributes of. I dislike any T-SQL that requires square brackets around names, but I have renamed a Users table to the singular, forever sentencing those using the table to sometimes have to use brackets. My gut feel is that it is more correct to stay with the singular, but my gut feel is also that brackets indicate undesirables like column names with spaces in them etc. Should I stay, or should I go?

    Read the article

  • Proper color names from colordialog

    - by Mike
    Whenever I run this, and open the color dialog, there are many colors that do not having a proper name, the listbox will show something like "ffff8000"(Orange-Yellow). Is there another way of pushing the proper name? Is there a proper Color Name library I can reference in code? colorDialog1.ShowDialog(); cl.Add(colorDialog1.Color.Name); listBox1.Items.AddRange(cl.ToArray());

    Read the article

  • What are the most popular version control softwares and why?

    - by gnucom
    Hey Everyone, I'm an employee at a small company that is going to be launching a version control system soon and I'm trying to consider which software would best serve this company for version control. I wanted to get as many opinions as possible. Right now, I'm experimenting with Trac and Indefero running atop a SVN server. So my question is, what is the most popular/favorite version control software and why? ??t??!

    Read the article

  • Naming of boolean column in database table

    - by Space Cracker
    I have 'Service' table and the following column description as below Is User Verification Required for service ? Is User's Email Activation Required for the service ? Is User's Mobile Activation required for the service ? I Hesitate in naming these columns as below IsVerificationRequired IsEmailActivationRequired IsMobileActivationRequired or RequireVerification RequireEmailActivation RequireMobileActivation I can't determined which way is the best .So, Is one of the above suggested name is the best or is there other better ones ?

    Read the article

  • How do you resolve the common collsision between type name and object name?

    - by Catskul
    Since the convention is to capitalize the first letter of public properties, the old c++ convention of initial capital for type names, and initial lowercase for non-type names does not prevent the classic name collision class FooManager { public BarManager BarManager { get; set; } // Feels very wrong. // Recommended naming convention? public int DoIt() { return Foo.Blarb + Foo.StaticBlarb; // 1st and 2nd Foo are two // different symbols } } class BarManager { public int Blarb { get; set; } public static int StaticBlarb { get; set; } } It seems to compile, but feels so wrong. Is there a recommend naming convention to avoid this?

    Read the article

  • Grammatically correct double-noun identifiers, plural versions

    - by Michal Czardybon
    Consider compounds of two nouns, which in natural English would most often appear in the form "noun of noun", e.g. "direction of light", "output of a filter". When programming we usually write "LightDirection" and "FilterOutput". Now, I have a problem with plural nouns. There are two cases: 1) singular of plural e.g. "union of (two) sets", "intersection of (two) segments" Which is correct, SetUnion and SegmentIntersection or SetsUnion and SegmentsIntersection? 2) plural of plural There are two subcases: (a) Many elements, each having many related elements, e.g. "outputs of filters" (b) Many elements, each having single related element, e.g. "directions of vectors" Shell I use FilterOutputs and VectorDirections or FiltersOutputs and VectorsDirections? I suspect correct is the first version (FilterOutupts, VectorDirections), but I think it may lead to ambiguities, e.g. FilterOutputs - many outputs of a single filter or many outputs of many filters? LineSegmentProjections - projections of many segments or many projections of a single segment?

    Read the article

  • Python List length as a string

    - by mvid
    Is there a preferred (not ugly) way of outputting a list length as a string? Currently I am nesting function calls like so: print "Length: %s" % str(len(self.listOfThings)) This seems like a hack solution, is there a more graceful way of achieving the same result?

    Read the article

  • naming a function that exhibits "set if not equal" behavior

    - by Chris Sears
    This might be an odd question, but I'm looking for a word to use in a function name. I'm normally good at coming up with succinct, meaningful function names, but this one has me stumped so I thought I'd appeal for help. The function will take some desired state as an argument and compare it to the current state. If no change is needed, the function will exit normally without doing anything. Otherwise, the function will take some action to achieve the desired state. For example, if wanted to make sure the front door was closed, i might say: my_house.<something>_front_door('closed') What word or term should use in place of the something? I'd like it to be short, readable, and minimize the astonishment factor. A couple clarifying points... I would want someone calling the function to intuitively know they didn't need to wrap the function an 'if' that checks the current state. For example, this would be bad: if my_house.front_door_is_open(): my_house.<something>_front_door('closed') Also, they should know that the function won't throw an exception if the desired state matches the current state. So this should never happen: try: my_house.<something>_front_door('closed') except DoorWasAlreadyClosedException: pass Here are some options I've considered: my_house.set_front_door('closed') my_house.setne_front_door('closed') # ne=not equal, from the setne x86 instruction my_house.ensure_front_door('closed') my_house.configure_front_door('closed') my_house.update_front_door('closed') my_house.make_front_door('closed') my_house.remediate_front_door('closed') And I'm open to other forms, but most I've thought of don't improve readability. Such as... my_house.ensure_front_door_is('closed') my_house.conditionally_update_front_door('closed') my_house.change_front_door_if_needed('closed') Thanks for any input!

    Read the article

< Previous Page | 6 7 8 9 10 11 12 13 14 15 16 17  | Next Page >