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  • handle null values for string when implementing IXmlSerializable interface

    - by user208081
    I have the following class that implements IXmlSerializable. When implementing WriteXml(), I need to handle the case where the string members of this class may be null values. What is the best way of handling this? Currently, I am using the default constructor in which all the string properties are initialized to empty string values. This way, when WriteXml() is called, the string will not be null. One other way I could do this is check using String.IsNullOrEmpty before writing each string in xml. Any suggestions on how I can improve this code? using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Xml.Serialization; using System.Globalization; namespace TCS.Common.InformationObjects { public sealed class FaxSender : IXmlSerializable { #region Public Constants private const string DEFAULT_CLASS_NAME = "FaxSender"; #endregion Public Constants #region Public Properties public string Name { get; set; } public string Organization { get; set; } public string PhoneNumber { get; set; } public string FaxNumber { get; set; } public string EmailAddress { get; set; } #endregion Public Properties #region Public Methods #region Constructors public FaxSender() { Name = String.Empty; Organization = String.Empty; PhoneNumber = String.Empty; FaxNumber = String.Empty; EmailAddress = String.Empty; } public FaxSender(string name, string organization, string phoneNumber, string faxNumber, string emailAddress) { Name = name; Organization = organization; PhoneNumber = phoneNumber; FaxNumber = faxNumber; EmailAddress = emailAddress; } #endregion Constructors #region IXmlSerializable Members public System.Xml.Schema.XmlSchema GetSchema() { throw new NotImplementedException(); } public void ReadXml(System.Xml.XmlReader reader) { throw new NotImplementedException(); } public void WriteXml(System.Xml.XmlWriter xmlWriter) { try { // <sender> xmlWriter.WriteStartElement("sender"); // Write the name of the sender as an element. xmlWriter.WriteElementString("name", this.Name.ToString(CultureInfo.CurrentCulture)); // Write the organization of the sender as an element. xmlWriter.WriteElementString("organization", this.Organization.ToString(CultureInfo.CurrentCulture)); // Write the phone number of the sender as an element. xmlWriter.WriteElementString("phone_number", this.PhoneNumber.ToString(CultureInfo.CurrentCulture)); // Write the fax number of the sender as an element. xmlWriter.WriteElementString("fax_number", this.FaxNumber.ToString(CultureInfo.CurrentCulture)); // Write the email address of the sender as an element. xmlWriter.WriteElementString("email_address", this.EmailAddress.ToString(CultureInfo.CurrentCulture)); // </sender> xmlWriter.WriteEndElement(); } catch { // Rethrow any exceptions. throw; } } #endregion IXmlSerializable Members #endregion Public Methods } }

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  • Linq to SQL and concurrency with Rob Conery repository pattern

    - by David Hall
    I have implemented a DAL using Rob Conery's spin on the repository pattern (from the MVC Storefront project) where I map database objects to domain objects using Linq and use Linq to SQL to actually get the data. This is all working wonderfully giving me the full control over the shape of my domain objects that I want, but I have hit a problem with concurrency that I thought I'd ask about here. I have concurrency working but the solution feels like it might be wrong (just one of those gitchy feelings). The basic pattern is: private MyDataContext _datacontext private Table _tasks; public Repository(MyDataContext datacontext) { _dataContext = datacontext; } public void GetTasks() { _tasks = from t in _dataContext.Tasks; return from t in _tasks select new Domain.Task { Name = t.Name, Id = t.TaskId, Description = t.Description }; } public void SaveTask(Domain.Task task) { Task dbTask = null; // Logic for new tasks omitted... dbTask = (from t in _tasks where t.TaskId == task.Id select t).SingleOrDefault(); dbTask.Description = task.Description, dbTask.Name = task.Name, _dataContext.SubmitChanges(); } So with that implementation I've lost concurrency tracking because of the mapping to the domain task. I get it back by storing the private Table which is my datacontext list of tasks at the time of getting the original task. I then update the tasks from this stored Table and save what I've updated This is working - I get change conflict exceptions raised when there are concurrency violations, just as I want. However, it just screams to me that I've missed a trick. Is there a better way of doing this? I've looked at the .Attach method on the datacontext but that appears to require storing the original version in a similar way to what I'm already doing. I also know that I could avoid all this by doing away with the domain objects and letting the Linq to SQL generated objects all the way up my stack - but I dislike that just as much as I dislike the way I'm handling concurrency.

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  • jQuery getJson returning null

    - by Adam
    I'm trying to use this api that lets you reference an exact text, but the getJson does not seem to be working, it's just returning null. $.getJSON('http://api.biblia.com/v1/bible/content/KJV.json?key=MYAPIKEY=John+3:16-18&style=bibleTextOnly', function(data) { alert(data); }); I just took the key out, i've been testing it with my real api key, and it works fine when i just visit the url. is there anything else i need to do to make it work? This is what you get from the url when you have an api key in the url: {"text":"For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life. For God sent not his Son into the world to condemn the world; but that the world through him might be saved. He that believeth on him is not condemned: but he that believeth not is condemned already, because he hath not believed in the name of the only begotten Son of God."}

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  • Android 2.1 View's getDrawingCache() method always returns null

    - by Impression
    Hello, I'm working with Android 2.1 and have the following problem: Using the method View.getDrawingCache() always returns null. Example code: public void onCreate(final Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); final View view = findViewById(R.id.ImageView01); view.setDrawingCacheEnabled(true); view.buildDrawingCache(); final Bitmap bmp = view.getDrawingCache(); System.out.println(bmp); } I've already tried different ways to configure the View object for generating the drawing cache (e.g. View.setWillNotDraw(boolean) and View.setWillNotCacheDrawing(boolean)), but nothing works. What is the right ways, or what do I wrong?

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  • Null-coalescing operator and operator && in C#

    - by abatishchev
    Is it possible to use together any way operator ?? and operator && in next case: bool? Any { get { var any = this.ViewState["any"] as bool?; return any.HasValue ? any.Value && this.SomeBool : any; } } This means next: if any is null then this.Any.HasValue return false if any has value, then it returns value considering another boolean property, i.e. Any && SomeBool

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  • preg_match , pattern, php

    - by Michael
    I'm trying to extract some specific pictures from html content . Currently I have the following array [1] = Array ( [0] = BuEZm5g!Wk~$(KGrHqQH-DgEvrb2CLuOBL-vbkHlKw~~_14.JPG#!BuEZm5g!Wk~$(KGrHqQH-DgEvrb2CLuOBL-vbkHlKw~~_12.JPG|1#http://i.ebayimg.com/08#!BuEZqMQBGk~$(KGrHqQH-DoEvrKYSoPiBL-vb)WgLw~~_14.JPG#!BuEZqMQBGk~$(KGrHqQH-DoEvrKYSoPiBL-vb)WgLw~~_12.JPG|2#http://i.ebayimg.com/13#!BuEZtkw!2k~$(KGrHqYH-EYEvsh4EjJSBL-vb-bLow~~_14.JPG#!BuEZtkw!2k~$(KGrHqYH-EYEvsh4EjJSBL-vb-bLow~~_12.JPG|3#http://i.ebayimg.com/03#!BuEZ)!wEGk~$(KGrHqYH-DwEvq8Z1JuQBL-vcMOoFQ~~_14.JPG#!BuEZ)!wEGk~$(KGrHqYH-DwEvq8Z1JuQBL-vcMOoFQ~~_12.JPG|4#http://i.ebayimg.com/09#!BuEZ1IQEGk~$(KGrHqEH-D0EvqwClvviBL-vcclJwg~~_14.JPG#!BuEZ1IQEGk~$(KGrHqEH-D0EvqwClvviBL-vcclJwg~~_12.JPG|5#http://i.ebayimg.com/17#!BuEZ4FQCWk~$(KGrHqUH-DMEvS+,FRj5BL-vco)Qgg~~_14.JPG#!BuEZ4FQCWk~$(KGrHqUH-DMEvS+,FRj5BL-vco)Qgg~~_12.JPG|6#http://i.ebayimg.com/17#!BuEZ7FQEWk~$(KGrHqYH-EYEvsh4EjJSBL-vc1v2Hg~~_14.JPG#!BuEZ7FQEWk~$(KGrHqYH-EYEvsh4EjJSBL-vc1v2Hg~~_12.JPG|7#http://i.ebayimg.com/12#!BuEZ-c!Bmk~$(KGrHqQH-CYEvr5z9)NVBL-vdC,)Mg~~_14.JPG#!BuEZ-c!Bmk~$(KGrHqQH-CYEvr5z9)NVBL-vdC,)Mg~~_12.JPG|8#http://i.ebayimg.com/20#!BuE,CNgCWk~$(KGrHqIH-CIEvqKBurmhBL-vdRBe3!~~_14.JPG#!BuE,CNgCWk~$(KGrHqIH-CIEvqKBurmhBL-vdRBe3!~~_12.JPG|9#http://i.ebayimg.com/24#!BuE,FN!EWk~$(KGrHqUH-C0EvsBdjbv0BL-vdeFkD!~~_14.JPG#!BuE,FN!EWk~$(KGrHqUH-C0EvsBdjbv0BL-vdeFkD!~~_12.JPG|10#http://i.ebayimg.com/16#!BuE,IOgBmk~$(KGrHqEH-EMEvpym7mSLBL-vdqI6nw~~_14.JPG#!BuE,IOgBmk~$(KGrHqEH-EMEvpym7mSLBL-vdqI6nw~~ ) I need to extract only the pictures that start with ! and ends in 12.JPG . An example of expected result is !BuEZm5g!Wk~$(KGrHqQH-DgEvrb2CLuOBL-vbkHlKw~~_12.JPG . I have a pattern but it doesn't work for some reasons that I don't know . It is $pattern = "/#\!(.*)_12.JPG/"; Thank you in advance for any help

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  • Null Pointer Exception on a 2D array (Java)

    - by user315156
    I have a class, "Tetris", in which one of the instance variables is "board". "board" is 2D array of Color objects. Upon the creation of a tetris object I call a method that sets the dimensions of board and then sets all of the Color objects to be the Default value, that is to say, Color.blue. public Tetris(int rows, int cols){ this.rows = rows; this.cols = cols; reset(rows, cols); } public void reset(int rows, int cols){ Color[][] board = new Color[rows][cols]; for(int i = 0; i Unfortunately, when I run the code (which obviously has not been posted in its entirety) I get a null pointer exception on the line: board[i][j] = DEFAULT_COLOR; // Color.blue; //DEFAULT-COLOR. Is there anything obviously wrong with what I am doing? (Sorry if there are glaring format issues, this is my first time on Stack Overflow)

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  • Database migration pattern for Java?

    - by Eno
    Im working on some database migration code in Java. Im also using a factory pattern so I can use different kinds of databases. And each kind of database im using implements a common interface. What I would like to do is have a migration check that is internal to the class and runs some database schema update code automatically. The actual update is pretty straight forward (I check schema version in a table and compare against a constant in my app to decide whether to migrate or not and between which versions of schema). To make this automatic I was thinking the test should live inside (or be called from) the constructor. OK, fair enough, that's simple enough. My problem is that I dont want the test to run every single time I instantiate a database object (it runs a query so having it run on every construction is not efficient). So maybe this should be a class static method? I guess my question is, what is a good design pattern for this type of problem? There ought to be a clean way to ensure the migration test runs only once OR is super-efficient.

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  • Fluent Nhibernate Automap convention for not-null field

    - by user215015
    Hi, Could some one help, how would I instruct automap to have not-null for a cloumn? public class Paper : Entity { public Paper() { } [DomainSignature] [NotNull, NotEmpty] public virtual string ReferenceNumber { get; set; } [NotNull] public virtual Int32 SessionWeek { get; set; } } But I am getting the following: <column name="SessionWeek"/> I know it can be done using fluent-map. but i would like to know it in auto-mapping way. Many thanks. Regards Robie

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  • Changing a SUM returned NULL to zero

    - by Lee_McIntosh
    I have a Stored Procedure as follows: CREATE PROC [dbo].[Incidents] (@SiteName varchar(200)) AS SELECT ( SELECT SUM(i.Logged) FROM tbl_Sites s INNER JOIN tbl_Incidents i ON s.Location = i.Location WHERE s.Sites = @SiteName AND i.[month] = DATEADD(mm, DATEDIFF(mm, 0, GetDate()) -1,0) GROUP BY s.Sites ) AS LoggedIncidents 'tbl_Sites contains a list of reported on sites. 'tbl_Incidents containts a generated list of total incidents by site/date (monthly) 'If a site doesnt have any incidents that month it wont be listed. The problem I'm having is that a site doesnt have any Incidents this month and as such i get a NULL value returned for that site when i run this sproc, but i need to have a zero/0 returned to be used within a chart in SSRS. I've tried the using coalesce and isnull to no avail. SELECT COALESCE(SUM(c.Logged,0)) SELECT SUM(ISNULL(c.Logged,0)) Is there a way to get this formatted correctly? Cheers, Lee

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  • django left join with null

    - by SledgehammerPL
    The model: class Product(models.Model): name = models.CharField(max_length = 128) def __unicode__(self): return self.name class Receipt(models.Model): name = models.CharField(max_length=128) components = models.ManyToManyField(Product, through='ReceiptComponent') class Admin: pass def __unicode__(self): return self.name class ReceiptComponent(models.Model): product = models.ForeignKey(Product) receipt = models.ForeignKey(Receipt) quantity = models.FloatField(max_length=9) unit = models.ForeignKey(Unit) def __unicode__(self): return unicode(self.quantity!=0 and self.quantity or '') + ' ' + unicode(self.unit) + ' ' + self.product.genitive The idea: there are a components on stock. I'd like to find out which recipes I can made with components which I have. It's not easy - but possible - I made a SQL view, which gets the solution. But I'm learning python and Django so I'd like to make it Django-style ;D The concept of solution: get the set of recipes which has at last one component: list_of_available_components = ReceiptComponent.objects.filter(product__in=list_of_available_products).distinct() list_of_related_receipts = Receipt.objects.filter(receiptcomponent__in = list_of_available_components).distinct() get recipes (from list_of_related_receipts) which has not at last one component list_of_incomplete_recipes = (SELECT * FROM drinkbook_receiptcomponent LEFT JOIN drinkstore_stock_products USING(product_id) WHERE drinkstore_stock_products.stock_id IS NULL AND receipt_id IN (SELECT receipt_id FROM drinkbook_receiptcomponent JOIN drinkstore_stock_products USING(product_id))) get recipes (from list_of_related_receipts) which are not in "list_of_incomplete_recipes"

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  • Using a ControlParameter in FilterParameters when the property is null

    - by end-user
    I have a DataList and FormView; they have separate datasources, though they pull the same info. The FormView's datasource has a FilterExpression to pull whatever's been selected on the DataList. On first load, the SelectedValue of the DataList is null (naturally). I expect the FilterExpression to result in zero rows, but it doesn't. If I set the DefaultValue to 0, it does, but then the parameter never updates when I select something from the DataList. Am I doing it wrong?

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  • JavaScript Module Pattern - What about using "return this"?

    - by Rob
    After doing some reading about the Module Pattern, I've seen a few ways of returning the properties which you want to be public. One of the most common ways is to declare your public properties and methods right inside of the "return" statement, apart from your private properties and methods. A similar way (the "Revealing" pattern) is to provide simply references to the properties and methods which you want to be public. Lastly, a third technique I saw was to create a new object inside your module function, to which you assign your new properties before returning said object. This was an interesting idea, but requires the creation of a new object. So I was thinking, why not just use "this.propertyName" to assign your public properties and methods, and finally use "return this" at the end? This way seems much simpler to me, as you can create private properties and methods with the usual "var" or "function" syntax, or use the "this.propertyName" syntax to declare your public methods. Here's the method I'm suggesting: (function() { var privateMethod = function () { alert('This is a private method.'); } this.publicMethod = function () { alert('This is a public method.'); } return this; })(); Are there any pros/cons to using the method above? What about the others?

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  • Scheme: Mysterious void in pattern match.

    - by Schemer
    Hi. I am writing a function called annotate that uses match-lambda -- often with recursive calls to annotate. Here is one of the pattern matches: (`(lambda (,<param1> . ,<params>) ,<stmts>) `(CLOSURE ENV (,<param1> . ,<params>) (lambda (ENV) ,(map annotate (map (lambda (x) (append `(,<param1> . ,<params>) (list x))) `(,<stmts>)))))) However, when this pattern is matched this is what returns: '(CLOSURE ENV (x) (lambda (ENV) ((CLOSURE ENV (x y) (lambda (ENV) ((+ x y)))))) #<void>) Specifically I can't figure out where "void" is coming from. In fact, if I include the line: ,(displayln (map annotate (map (lambda (x) (append `(,<param1> . ,<params>) (list x))) `(,<stmts>)))) it prints: ((CLOSURE ENV (x y) (lambda (ENV) ((+ x y))))) notably without "void". If someone could tell me what the problem is it would be greatly appreciated. Thanks.

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  • Value cannot be null in sportstore exampe

    - by Naim
    Hi everyone, I am having this problem when I want to implement IoC for sportstore example. The code public WindsorControllerFactory(){ container = new WindsorContainer( new XmlInterpreter(new ConfigResource("castle")) ); var controllerTypes= from t in Assembly.GetExecutingAssembly().GetTypes() where typeof(IController).IsAssignableFrom(t) select t; foreach (Type t in controllerTypes) container.AddComponentLifeStyle(t.FullName, t, LifestyleType.Transient); } protected override IController GetControllerInstance(Type controllerType) { return (IController)container.Resolve(controllerType); } } The error said that the value cannot be null in the GetControllerInstance Any help will be appreciated ! Thanks! Naim

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  • EXCEL import to sql returning NULL for decimals when in VARCHAR data type

    - by Daniel
    Hi, I am working on a peice of software which has expodentially grown over the last few years and the database needs to be regularly updated. Customers are providing us with data now on large spreadsheets which we format and will start importing into the database. I am using the Import and Export Data (32-bit) Wizard. One column in the database contains values like '1.1.1.2' etc and i am importing them in as a Varchar as that is the data type in the database. However, for values like '8.5', 'NULL' is getting imported insead. It only occurs when there is one decimal point. Is this a formatting error with excel or is it the wrong datatype?

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  • Repository Pattern Standardization of methods

    - by Nix
    All I am trying to find out the correct definition of the repository pattern. My original understanding was this (extremely dubmed down) Separate your Business Objects from your Data Objects Standardize access methods in data access layer. I have really seen 2 different implementations. Implementation 1 : public Interface IRepository<T>{ List<T> GetAll(); void Create(T p); void Update(T p); } public interface IProductRepository: IRepository<Product> { //Extension methods if needed List<Product> GetProductsByCustomerID(); } Implementation 2 : public interface IProductRepository { List<Product> GetAllProducts(); void CreateProduct(Product p); void UpdateProduct(Product p); List<Product> GetProductsByCustomerID(); } Notice the first is generic Get/Update/GetAll, etc, the second is more of what I would define "DAO" like. Both share an extraction from your data entities. Which I like, but i can do the same with a simple DAO. However the second piece standardize access operations I see value in, if you implement this enterprise wide people would easily know the set of access methods for your repository. Am I wrong to assume that the standardization of access to data is an integral piece of this pattern ? Rhino has a good article on implementation 1, and of course MS has a vague definition and an example of implementation 2 is here.

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  • NULL pointer dereference in C

    - by user554125
    hey ive got this piece of code. It dereferences a null pointer here. But then there is an and with unsigned int. I really dont understand the whole part. Can someone explain the output.?? struct hi { long a; int b; long c; }; int main() { struct hi ob={3,4,5}; struct hi *ptr=&ob; int num= (unsigned int) & (((struct hi *)0)->b); printf("%d",num); printf("%d",*(int *)((char *)ptr + (unsigned int) & (((struct hi *)0)->b))); } The o/p i get is 44 .But how does it work?

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  • Object reference not set to an instance of an object- Linked List Example

    - by Zoro Roronoa
    I am seeing following errors : Object reference not set to an instance of an object! Check to determinate if the object is null before calling the method! I'am new with C#,and I made a program for Sorted Linked Lists. Here is the code where the error comes! public void Insert(double data) { Link newLink = new Link(data); Link current = first; Link previous = null; if (first == null) { first = newLink; } else { while (data > current.DData && current != null) { previous = current; current = current.Next; } previous.Next = newLink; newLink.Next = current; } } It says that the current referenc is null while (data current.DData && current != null), but I assigned it current = first; Please Help ! The rest is the complete code of the Program! class Link { double dData; Link next=null; public Link Next { get { return next; } set { next = value; } } public double DData { get { return dData; } set { dData = value; } } public Link(double dData) { this.dData = dData; } public void DisplayLink() { Console.WriteLine("Link : "+ dData); } } class SortedList { Link first; public SortedList() { first = null; } public bool IsEmpty() { return (this.first == null); } public void Insert(double data) { Link newLink = new Link(data); Link current = first; Link previous = null; if (first == null) { first = newLink; } else { while (data > current.DData && current != null) { previous = current; current = current.Next; } previous.Next = newLink; newLink.Next = current; } } public Link Remove() { Link temp = first; first = first.Next; return temp; } public void DisplayList() { Link current; current = first; Console.WriteLine("Display the List!"); while (current != null) { current.DisplayLink(); current = current.Next; } } } class SortedListApp { public void TestSortedList() { SortedList newList = new SortedList(); newList.Insert(20); newList.Insert(22); newList.Insert(100); newList.Insert(1000); newList.Insert(15); newList.Insert(11); newList.DisplayList(); newList.Remove(); newList.DisplayList(); } }

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  • Casting an object which could be null

    - by DeeMac
    DateTime? testDate = (DateTime?)arrayOfObjects[dateObject]; Does that code look ok? I attempted to use the as operator but I got the 'non-nullable' error. What I'm trying to say is that the object I'm choosing from the array is either DateTime or a null DateTime but either can be assigned to testDate. Doesn't feel right doing it this way, I think I'm missing something obvious. EDIT: I suppose it's the same as the way I could've adapted the as in the following way: DateTime? testDate = arrayOfObjects[dateObject] as DateTime?; Is either line of code the best way of handling potential nulls?

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  • Return Empty String as NULL

    - by Daniel
    I have a listbox select and I want when the user selects null for the empty string it produces to pull the nulls from the SQL table. Here's what I have now. Blank strings return nothing because there are no empty fields in the table. SELECT * FROM dbo.Table WHERE ID = " & TextBox2.Text & " and And Field1 IN (" & Msg1 & ") How do I code that?

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  • Can an object oriented program be seen as a Finite State Machine?

    - by Peretz
    This might be a philosophical/fundamental question, but I just want to clarify it. In my understanding a Finite State Machine is a way of modeling a system in which the system's output will not only depend on the current inputs, but also the current state of the system. Additionally, as the name suggests it, a finite state machine can be segmented in a finite N number of states with its respective state and behavior. If this is correct, shouldn't every single object with data and function members be a state in our object oriented model, making any object oriented design a finite state machine? If that is not the interpretation of a FSM in object design, what exactly people mean when they implement a FSM in software? am I missing something? Thanks

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  • Breaking up a large PHP object used to abstract the database. Best practices?

    - by John Kershaw
    Two years ago it was thought a single object with functions such as $database->get_user_from_id($ID) would be a good idea. The functions return objects (not arrays), and the front-end code never worries about the database. This was great, until we started growing the database. There's now 30+ tables, and around 150 functions in the database object. It's getting impractical and unmanageable and I'm going to be breaking it up. What is a good solution to this problem? The project is large, so there's a limit to the extent I can change things. My current plan is to extend the current object for each table, then have the database object contain these. So, the above example would turn into (assume "user" is a table) $database->user->get_user_from_id($ID). Instead of one large file, we would have a file for every table.

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  • Questioning one of the arguments for dependency injection: Why is creating an object graph hard?

    - by oberlies
    Dependency injection frameworks like Google Guice give the following motivation for their usage (source): To construct an object, you first build its dependencies. But to build each dependency, you need its dependencies, and so on. So when you build an object, you really need to build an object graph. Building object graphs by hand is labour intensive (...) and makes testing difficult. But I don't buy this argument: Even without dependency injection, I can write classes which are both easy to instantiate and convenient to test. E.g. the example from the Guice motivation page could be rewritten in the following way: class BillingService { private final CreditCardProcessor processor; private final TransactionLog transactionLog; // constructor for tests, taking all collaborators as parameters BillingService(CreditCardProcessor processor, TransactionLog transactionLog) { this.processor = processor; this.transactionLog = transactionLog; } // constructor for production, calling the (productive) constructors of the collaborators public BillingService() { this(new PaypalCreditCardProcessor(), new DatabaseTransactionLog()); } public Receipt chargeOrder(PizzaOrder order, CreditCard creditCard) { ... } } So there may be other arguments for dependency injection (which are out of scope for this question!), but easy creation of testable object graphs is not one of them, is it?

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  • Is there an alternative to the term "calling object"?

    - by ybakos
    Let's suppose you've got a class defined (in pseudocode): class Puppy { // ... string sound = "Rawr!"; void bark() { print(sound); } } And say, given a Puppy instance, you call it's bark() method: Puppy p; p.bark(); Notice how bark() uses the member variable sound. In many contexts, I've seen folks describe sound as the member variable of the "calling object." My question is, what's a better term to use than "calling object?" To me, the object is not doing any calling. We know that member functions are in a way just functions with an implicit this or self parameter. I've come up with "receiving object," or "message recipient," which makes sense if you're down with the "messaging" paradigm. Do any of you happy hackers have a term that you like to use? I feel it should mean "the object upon which a method is called" and TOUWAMIC just doesn't cut it.

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