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• NHibernate Query object collection issue

  - by Mahesh

  Hi, I am new to NHibernate and need some information regarding the internal working of the engine: I have a table called Student and the design is as follows: RollNo Name City Postcode and there are 5 more columns like this. I have School class and mappings associated with it. I am querying RollNo and Name using session as given below: IQuery query = session.CreateQuery("SELECT RollNo,Name FROM Student); Executing query.List resulting in error because the query is returning object[][]. Now, I changed the query as given below: IQuery query = session.CreateQuery("FROM Student); Executing query.List on this query yeilds the desired results. But, the results contain more data than I want. Could you please let me know the query to which I can get RollNo and Name from Student and castable as Student collection. Thanks, Mahesh

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• design pattern for unit testing?

  - by Maddy.Shik

  I am beginner in developing test cases, and want to follow good patterns for developing test cases rather than following some person or company's specific ideas. Some people don't make test cases and just develop the way their senior have done in their projects. I am facing lot problems like object dependencies (when want to test method which persist A object i have to first persist B object since A is child of B). Please suggest some good books or sites preferably for learning design pattern for unit test cases. Or reference to some good source code or some discussion for Dos and Donts will do wonder. So that i can avoid doing mistakes be learning from experience of others.

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• Javascript: Error 'Object Required.'

  - by javascripthelp

  The following is the error popup message I get when I click "Finalize" button on my website: "Line: 298 Char: 5 Error: Object required: 'lobi_c_selected(...)' Code: 0 URL: http://10.128.23.50/i-prostage/AP/w_ap_check_reconciliation.asp?" Normally, when I click "Finalize" button, it'll generate and show a report in a popup window. However, I'd get this error message instead. Can any of you help me locate the error in the following source code for the page that I'm running in IE 6? sub cb_finalize dim ll_loop, ll_found, lobj_c_selected of_SetHourGlass(True) rpt_link.innerHTML = "" rpt_link.href = "" 'Process only if at least one record was selected if rds1.Recordset.Recordcount 0 then lb_found = false if rds1.Recordset.Recordcount = 1 then if c_selected.checked then lb_found = true else Set lobj_c_selected = document.all.item("c_selected") for ll_loop = 1 to rds1.Recordset.Recordcount if lobj_c_selected(ll_loop - 1).checked then lb_found = true exit for end if next end if if not lb_found then msgbox "Please select a record to be posted.", vbInformation, "ProStage Accounting" of_SetHourGlass(False) else window.setTimeout "ue_process()", 100, vbscript 'Post Event end if else msgbox "There's no record to be posted." + vbcrlf + "Please select a record to be posted.", vbInformation, "ProStage Accounting" of_SetHourGlass(False) end if end sub Sub ue_process dim ll_loop, ll_count, ls_ret, ls_trxid, ls_r1 'Get only selected records redim ls_trxid(rds1.Recordset.Recordcount) for ll_loop = 1 to rds1.Recordset.Recordcount rds1.Recordset.AbsolutePosition = ll_loop if not isnull(rds1.Recordset("clrdt")) then 'Add to TRXID array if selected ll_count = ll_count + 1 ls_trxid(ll_count) = rds1.Recordset("trxid") end if next 'Process reconciliation rds1.Recordset.MarshalOptions = 1 ls_ret = iBO_Update.of_update_1(is_dbsrc, rds1.Recordset, "GLTRX", is_sql) if ls_ret < "1" then msgbox "Update Failed ! " + ls_ret, vbExclamation + vbOKonly, document.title of_SetHourGlass(False) else 'Display Posting Journal & clear screen ue_posting_journal ls_trxid, ll_count Set rds1.SourceRecordset = iBO_Company.of_validate(is_dbsrc, "SELECT 1 FROM DUAL WHERE 1 = 2") ib_query = false 'Not to process RetrieveEnd end if End Sub Sub ue_posting_journal(as_trxid, al_count) dim ll_argseq, ls_argtyp, ls_argmnt, ll_sargseq of_setreport() ' Start service 'Prepare arguments for report in RPTMSTR table for ll_loop = 1 to al_count + 1 select case ll_loop case 1 'Range displayed as report title ll_argseq = 800 ls_argtyp = null ls_argmnt = "st_title.text = 'Bank: " + bnkid_name.value + ", As of Date: " + _ of_date_stringtodate(id_trxdt) + "'" ll_sargseq = 0 case else 'TRXID array ll_argseq = 1 ll_sargseq = ll_loop - 1 ls_argtyp = "S" ls_argmnt = as_trxid(ll_loop - 1) end select of_report_register_array "d_rpt_ap_check_reconciliation_register", ll_argseq, ls_argtyp, ls_argmnt, ll_sargseq next of_report_process "d_rpt_ap_check_reconciliation_register", true, true 'Display report of_sethourglass(False) End Sub

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• Matching the superclass's constructor's parameter list, is treating a null default value as a non-null value within a constructor a violation of LSP?

  - by Panzercrisis

  I kind of ran into this when messing around with FlashPunk, and I'm going to use it as an example. Essentially the main sprite class is pretty much class Entity. Entity's constructor has four parameters, each with a default value. One of them is graphic, whose default value is null. Entity is designed to be inherited from, with many such subclasses providing their own graphic within their own internal workings. Normally these subclasses would not have graphic in their constructor's parameter lists, but would simply pick something internally and go with it. However I was looking into possibly still adhering to the Liskov Substitution Principal. Which led me to the following example: package com.blank.graphics { import net.flashpunk.*; import net.flashpunk.graphics.Image; public class SpaceGraphic extends Entity { [Embed(source = "../../../../../../assets/spaces/blank.png")] private const BLANK_SPACE:Class; public function SpaceGraphic(x:Number = 0, y:Number = 0, graphic:Graphic = null, mask:Mask = null) { super(x, y, graphic, mask); if (!graphic) { this.graphic = new Image(BLANK_SPACE); } } } } Alright, so now there's a parameter list in the constructor that perfectly matches the one in the super class's constructor. But if the default value for graphic is used, it'll exhibit two different behaviors, depending on whether you're using the subclass or the superclass. In the superclass, there won't be a graphic, but in the subclass, it'll choose the default graphic. Is this a violation of the Liskov Substitution Principal? Does the fact that subclasses are almost intended to use different parameter lists have any bearing on this? Would minimizing the parameter list violate it in a case like this? Thanks.

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• Should I make the Cells in a Tiledmap as null when my player hits it

  - by Vishal Kumar

  I am making a Tile Based game using Libgdx. I took the idea from SuperKoalio platformer demo by Mario Zencher. When I wanted to implement Collectables in my game , I simply draw the coins using Tiled Map Editor. When my player hits that, I use to set that cell as null. Someday on this site suggested me not to do so... never use null. I agreed. What can be any other way. If I am using layer.setCell(x,y) to set the cell to any other cell... even if an transparent one .. my player seems to be stopped by an invisible object/hurdle. This is my code: for (Rectangle tile : tiles) { if (koalaRect.overlaps(tile)) { TiledMapTileLayer layer = (TiledMapTileLayer) map.getLayers().get(1); try{ type = layer.getCell((int) tile.x, (int) tile.y).getTile().getProperties().get("tileType").toString(); } catch(Exception e){ System.out.print("Exception in Tiles Property"+e); type="nonbreakable"; } //Let us destroy this cell if(("award".equals(type))){ layer.setCell((int) tile.x, (int) tile.y, null); listener.coin(); score+=100; test = ""+layer.getCell(0, 0).getTile().getProperties().get("tileType"); } //DOING THIS GIVES A BAD EFFECT if(("killer".equals(type))){ //player.health--; //layer.setCell((int) tile.x, (int) tile.y, layer.getCell(20,0)); } // we actually reset the player y-position here // so it is just below/above the tile we collided with // this removes bouncing :) if (player.velocity.y > 0) { player.position.y = (tile.y - Player.height); } Is this a right approach? OR I should create separate Sprite Class called Coin.

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• How are java.lang.Object's protected methods protected from subclasses?

  - by Adrian Lang

  The keyword protected grants access to classes in the same package and subclasses (http://java.sun.com/docs/books/tutorial/java/javaOO/accesscontrol.html). Now, every class has java.lang.Object as superclass (http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Object.html). Hence I conclude that every class may access java.lang.Object's methods even if they are protected. Take a look at the following example: public class Testclass { public Object getOne() throws CloneNotSupportedException { return this.clone(); } public Object getTwo() throws CloneNotSupportedException { return ((Object) this).clone(); } } While getOne() compiles fine, getTwo() gives Testclass.java:6: clone() has protected access in java.lang.Object return ((Object) this).clone(); I neither understand why getTwo() doesn't compile nor what's the difference (regarding the access of java.lang.Objects members) with getOne().

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• Hibernate -using Table per subclass - how to link an existing superclass object to a sibclass object

  - by Chandni

  Hi, I have a User hibernate class, Clerk class and Consumer class. All these maps to their own tables in database. The User PK also acts as Clerk's and Consumer's PK. So now my problem is that if a user is initially a Clerk, he has a record in Users table and Clerks table. If that user wants to become a consumer, I want to link that User's record to the new Consumer's record. So even if I pass the userId to the consumer's record, it treats it as a new User to be persisted and gives a duplicate_key exception. How do I tell Hiernate to link the same user object with this new Consumer object. Thanks in advance, -Chandni

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• TSQL Help (SQL Server 2005)

  - by Mick Walker

  I have been playing around with a quite complex SQL Statement for a few days, and have gotten most of it working correctly. I am having trouble with one last part, and was wondering if anyone could shed some light on the issue, as I have no idea why it isnt working: INSERT INTO ExistingClientsAccounts_IMPORT SELECT DISTINCT cca.AccountID, cca.SKBranch, cca.SKAccount, cca.SKName, cca.SKBase, cca.SyncStatus, cca.SKCCY, cca.ClientType, cca.GFCID, cca.GFPID, cca.SyncInput, cca.SyncUpdate, cca.LastUpdatedBy, cca.Deleted, cca.Branch_Account, cca.AccountTypeID FROM ClientsAccounts AS cca INNER JOIN (SELECT DISTINCT ClientAccount, SKAccount, SKDesc, SKBase, SKBranch, ClientType, SKStatus, GFCID, GFPID, Account_Open_Date, Account_Update FROM ClientsAccounts_IMPORT) AS ccai ON cca.Branch_Account = ccai.ClientAccount Table definitions follow: CREATE TABLE [dbo].[ExistingClientsAccounts_IMPORT]( [AccountID] [int] NOT NULL, [SKBranch] [varchar](2) NOT NULL, [SKAccount] [varchar](12) NOT NULL, [SKName] [varchar](255) NULL, [SKBase] [varchar](16) NULL, [SyncStatus] [varchar](50) NULL, [SKCCY] [varchar](5) NULL, [ClientType] [varchar](50) NULL, [GFCID] [varchar](10) NULL, [GFPID] [varchar](10) NULL, [SyncInput] [smalldatetime] NULL, [SyncUpdate] [smalldatetime] NULL, [LastUpdatedBy] [varchar](50) NOT NULL, [Deleted] [tinyint] NOT NULL, [Branch_Account] [varchar](16) NOT NULL, [AccountTypeID] [int] NOT NULL ) ON [PRIMARY] CREATE TABLE [dbo].[ClientsAccounts_IMPORT]( [NEWClientIndex] [bigint] NOT NULL, [ClientGroup] [varchar](255) NOT NULL, [ClientAccount] [varchar](255) NOT NULL, [SKAccount] [varchar](255) NOT NULL, [SKDesc] [varchar](255) NOT NULL, [SKBase] [varchar](10) NULL, [SKBranch] [varchar](2) NOT NULL, [ClientType] [varchar](255) NOT NULL, [SKStatus] [varchar](255) NOT NULL, [GFCID] [varchar](255) NULL, [GFPID] [varchar](255) NULL, [Account_Open_Date] [smalldatetime] NULL, [Account_Update] [smalldatetime] NULL, [SKType] [varchar](255) NOT NULL ) ON [PRIMARY] The error message I get is: Msg 8152, Level 16, State 14, Line 1 String or binary data would be truncated. The statement has been terminated.

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• Join two tables with same # of row but sorted for NULL

  - by VISQL

  I need to join two tables with the same number of rows. Each table has 1 column. There is NO CONNECTING COLUMN to reference for a join. I need to join them side by side because each table was sorted separately so that numeric values are at the top in descinding order. The Table Earners has income values from say 200K down to 0. I cannot just select using 2 cases, because then I will have my first row with Incomes above 100K, but the first 20 or so entries in the second row are NULL. I want the second row to also be sorted descending. I looked up using ORDER BY within CASE but there is no such thing. I have tried to read about row_number() but none of the examples seem to match or make sense. drop table #20plus select case when Income >= 20000 AND Income < 100000 then Income end as 'mula' into #20plus from Earners order by mula desc drop table #100plus select case when Income >= 100000 then Income end as 'dinero' into #100plus from Earners order by dinero desc Select A.dinero, B.mula FROM #100plus as A JOIN #20plus as B ON A.????? = B.????? Since both A and B are sorted descending, moving all NULL to the bottom, what can I reference to join the two tables? Previous output using one SELECT statement with 2 CASE statements dinero mula 2.12688e+007 NULL 1.80031e+007 NULL 1.92415e+006 NULL … … NULL 93530.7 NULL 91000 NULL 84500 Desired output using one SELECT statement after creating two temp TABLES dinero mula 2.12688e+007 93530.7 1.80031e+007 91000 1.92415e+006 84500 … 82500 NULL 82000 NULL … NULL NULL This is Microsoft SQL Server 2008. I'm super new to this, so please give an answer as clear and simplified as possible. Thank you.

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• Is it good to subclass a class only to separate some functional parts?

  - by prostynick

  Suppose we have abstract class A (all examples in C#) public abstract class A { private Foo foo; public A() { } public void DoSomethingUsingFoo() { //stuff } public void DoSomethingElseUsingFoo() { //stuff } //a lot of other stuff... } But we are able to split it into two classes A and B: public abstract class A { public A() { } //a lot of stuff... } public abstract class B : A { private Foo foo; public B() : base() { } public void DoSomethingUsingFoo() { //stuff } public void DoSomethingElseUsingFoo() { //stuff } //nothing else or just some overrides of A stuff } That's good, but we are 99.99% sure, that no one will ever subclass A, because functionality in B is very important. Is it still good to have two separate classes only to split some code into two parts and to separate functional elements?

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• Design Pattern for building a Budget

  - by Scott

  So I've looked at the Builder Pattern, Abstract Interfaces, other design patterns, etc. - and I think I'm over thinking the simplicity behind what I'm trying to do, so I'm asking you guys for some help with either recommending a design pattern I should use, or an architecture style I'm not familiar with that fits my task. So I have one model that represents a Budget in my code. At a high level, it looks like this: public class Budget { public int Id { get; set; } public List<MonthlySummary> Months { get; set; } public float SavingsPriority { get; set; } public float DebtPriority { get; set; } public List<Savings> SavingsCollection { get; set; } public UserProjectionParameters UserProjectionParameters { get; set; } public List<Debt> DebtCollection { get; set; } public string Name { get; set; } public List<Expense> Expenses { get; set; } public List<Income> IncomeCollection { get; set; } public bool AutoSave { get; set; } public decimal AutoSaveAmount { get; set; } public FundType AutoSaveType { get; set; } public decimal TotalExcess { get; set; } public decimal AccountMinimum { get; set; } } To go into more detail about some of the properties here shouldn't be necessary, but if you have any questions about those I will fill more out for you guys. Now, I'm trying to create code that builds one of these things based on a set of BudgetBuildParameters that the user will create and supply. There are going to be multiple types of these parameters. For example, on the sites homepage, there will be an example section where you can quickly see what your numbers look like, so they would be a much simpler set of SampleBudgetBuildParameters then say after a user registers and wants to create a fully filled out Budget using much more information in the DebtBudgetBuildParameters. Now a lot of these builds are going to be using similar code for certain tasks, but might want to also check the status of a users DebtCollection when formulating a monthly spending report, where as a Budget that only focuses on savings might not want to. I'd like to reduce code duplication (obviously) as much as possible, but in my head, every way I can think to do this would require using a base BudgetBuilderFactory to return the correct builder to the caller, and then creating say a SimpleBudgetBuilder that inherits from a BudgetBuilder, and put all duplicate code in the BudgetBuilder, and let the SimpleBudgetBuilder handle it's own cases. Problem is, a lot of the unique cases are unique to 2/4 builders, so there will be duplicate code somewhere in there obviously if I did that. Can anyone think of a better way to either explain a solution to this that may or may not be similar to mine, or a completely different pattern or way of thinking here? I really appreciate it.

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• Converting HTML TAG Object to JSON Object

  - by cooldude

  Hi, I want to convert the html tag objects to json object in the javascript in order to send them to the server from the javascript. As i have to save these objects at the Ruby on Rails server. These HTML objects is the canvas tag object and the graphics objects created using CAKE API. I have used the stringify function but it is not working. Here is my code: var CAKECanvas = new Canvas(document.body, 1000,1000); var canvas=CAKECanvas.canvas; var text=document.createElement('textarea'); text.id="text"; text.rows="100"; text.cols="200"; document.body.appendChild(text); canvas.style.borderStyle="solid"; canvas.style.borderColor="black"; var rect= new Circle(); rect.radius=100; rect.centered=true; rect.cx=Math.random() * 500; rect.cy= Math.random() * 300; rect.stroke= false; rect.fill= "red"; rect.xDir = Math.random() > 0.5?1:-1; rect.yDir = Math.random() > 0.5?1:-1; var obj=new Object; var count = 0,k; for (k in rect) { if (rect.hasOwnProperty(k)) { count++; obj[k]=rect[k]; } } alert(count); rect.addFrameListener(function(t, dt) { this.cx += this.xDir * 50 * dt/1000; this.cy += this.yDir * 50 * dt/1000; if (this.cx > 550) { this.xDir = -1; } if (this.cx < 50) { this.xDir = 1; } if (this.cy > 350) { this.yDir = -1; } if (this.cy < 50) { this.yDir = 1; } } ); CAKECanvas.append(rect); var carAsJSON = JSON.stringify(obj); /////////////////ERROR

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• Creating an object relational schema from a Class diagram

  - by Caylem

  Hi Ladies and Gents. I'd like some help converting the following UML diagram: UML Diagram The diagram shows 4 classes and is related to a Loyalty card scheme for an imaginary supermarket. I'd like to create an object relational data base schema from it for use with Oracle 10g/11g. Not sure where to begin, if somebody could give me a head start that would be great. Looking for actually starting the schema, show abstraction, constraints, types(subtypes, supertypes) methods and functions. Note: I'm not looking for anyone to make any comments regarding the actual classes and whether changes should be made to the Diagram, just the schema. Thanks

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• Unable to create unmanaged object using new keyword in managed C++

  - by chair79

  Hi all, I've created a class with a boost::unordered_map as a member, Linkage.h #ifndef LINKAGE_H #define LINKAGE_H #include <boost/unordered_map.hpp> class Linkage { private: boost::unordered_map<int, int> m_IOMap; public: .... }; Linkage.cpp #include "stdafx.h" ... // methods and in the managed side of C++, I try to create the pointer of the obj: private: System::Void Form1_Load(System::Object^ sender, System::EventArgs^ e) { Linkage* m_pLink = new Linkage(); ..... } However this produces errors: Error 4 error LNK2005: "private: static unsigned int const boost::detail::type_with_alignment_imp<4>::found" (?found@?$type_with_alignment_imp@$03@detail@boost@@$$Q0IB) already defined in Proj_Test.obj Linkage.obj ..... Error 7 fatal error LNK1169: one or more multiply defined symbols found Could anyone explain to me pls? Thanks.

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• WPF Binding : Object in a object

  - by Philippe

  I have a form in WPF with 2 textbox : <TextBox Name="txtName" Text="{Binding Contact.Name}"/> <TextBox Name="txtAddressNumber" Text="{Binding Contact.Address.Number}"/> and I have 2 class : public class ContactEntity { public string Name {get;set;} public AddressEntity Address {get;set;} } public class AddressEntity { public int Number {get;set} } The Name property binds fine. But the Number property of the Address object inside the Contact object does not binds. What I'm doing wrong ?

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• OO and Writing Drupal Modules

  - by Aaron

  Preface: Yes, I've read: http://drupal.org/node/547518 I am writing 'foo' module for Drupal6, where I am organizing the code in an OO fashion. There's a class called Foo that has a bunch of setters and accessors, and it is working quite well at abstracting some pretty nasty code and SQL. The question is is it common practice to expose a class for other modules, or is it better to wrap things in the more typical foo_myfnname()? For example, if I am writing the module's docs, should I tell people to do this: $foo = new Foo(); $something = $foo->get_something(); or tell them to call: foo_get_something(); which under the hood does: function foo_get_something() { $foo = new Foo(); return $foo->get_something(); }

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• Behavior of <- NULL on lists versus data.frames for removing data

  - by Ananda Mahto

  Many R users eventually figure out lots of ways to remove elements from their data. One way is to use NULL, particularly when you want to do something like drop a column from a data.frame or drop an element from a list. Eventually, a user comes across a situation where they want to drop several columns from a data.frame at once, and they hit upon <- list(NULL) as the solution (since using <- NULL will result in an error). A data.frame is a special type of list, so it wouldn't be too tough to imagine that the approaches for removing items from a list should be the same as removing columns from a data.frame. However, they produce different results, as can be seen in the example below. ## Make some small data--two data.frames and two lists cars1 <- cars2 <- head(mtcars)[1:4] cars3 <- cars4 <- as.list(cars2) ## Demonstration that the `list(NULL)` approach works cars1[c("mpg", "cyl")] <- list(NULL) cars1 # disp hp # Mazda RX4 160 110 # Mazda RX4 Wag 160 110 # Datsun 710 108 93 # Hornet 4 Drive 258 110 # Hornet Sportabout 360 175 # Valiant 225 105 ## Demonstration that simply using `NULL` does not work cars2[c("mpg", "cyl")] <- NULL # Error in `[<-.data.frame`(`*tmp*`, c("mpg", "cyl"), value = NULL) : # replacement has 0 items, need 12 Switch to applying the same concept to a list, and compare the difference in behavior. ## Does not fully drop the items, but sets them to `NULL` cars3[c("mpg", "cyl")] <- list(NULL) # $mpg # NULL # # $cyl # NULL # # $disp # [1] 160 160 108 258 360 225 # # $hp # [1] 110 110 93 110 175 105 ## *Does* drop the `list` items while this would ## have produced an error with a `data.frame` cars4[c("mpg", "cyl")] <- NULL # $disp # [1] 160 160 108 258 360 225 # # $hp # [1] 110 110 93 110 175 105 The main questions I have are, if a data.frame is a list, why does it behave so differently in this scenario? Is there a foolproof way of knowing when an element will be dropped, when it will produce an error, and when it will simply be given a NULL value? Or do we depend on trial-and-error for this?

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• MVC Communication Pattern

  - by Kedu

  This is kind of a follow up question to this http://stackoverflow.com/questions/23743285/model-view-controller-and-callbacks, but I wanted to post it separately, because its kind of a different topic. I'm working on a multiplayer cardgame for the Android platform. I split the project into MVC which fits the needs pretty good, but I'm currently stuck because I can't figure out a good way to communicate between the different parts. I have everything setup and working with the controller being a big state machine, which is called over and over from the gameloop, and calls getter methods from the GUI and the android/network part to get the input. The input itself in the GUI and network is set by inputlisteners that set a local variable which I read in the getter method. So far so good, this is working. But my problem is, the controller has to check every input separately,so if I want to add an input I have to check in which states its valid and call the getter method from all these states. This is not good, and lets the code look pretty ugly, makes additions uncomfortable and adds redundance. So what I've got from the question I mentioned above is that some kind of command or event pattern will fit my needs. What I want to do is to create a shared and threadsafe queue in the controller and instead of calling all these getter methods, I just check the queue for new input and proceed it. On the other side, the GUI and network don't have all these getters, but instead create an event or command and send it to the controller through, for example, observer/observable. Now my problem: I can't figure out a way, for these commands/events to fit a common interface (which the queue can store) and still transport different kind of data (button clicks, cards that are played, the player id the command comes from, synchronization data etc.). If I design the communication as command pattern, I have to stick all the information that is needed to execute the command into it when its created, that's impossible because the GUI or network has no knowledge of all the things the controller needs to execute stuff that needs to be done when for example a card is played. I thought about getting this stuff into the command when executing it. But over all the different commands I have, I would need all the information the controller has, and thus give the command a reference to the controller which would make everything in it public, which is real bad design I guess. So, I could try some kind of event pattern. I have to transport data in the event. So, like the command, I would have an interface, which all events have in common, and can be stored in the shared queue. I could create a big enum with all the different events that a are possible, save one of these enums in the actual event, and build a big switch case for the events, to proceed different stuff for different events. The problem here: I have different data for all the events. But I need a common interface, to store the events in a queue. How do I get the specific data, if I can only access the event through the interface? Even if that wouldn't be a problem, I'm creating another big switch case, which looks ugly, and when i want to add a new event, I have to create the event itself, the case, the enum, and the method that's called with the data. I could of course check the event with the enum and cast it to its type, so I can call event type specific methods that give me the data I need, but that looks like bad design too.

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• Are null references really a bad thing?

  - by Tim Goodman

  I've heard it said that the inclusion of null references in programming languages is the "billion dollar mistake". But why? Sure, they can cause NullReferenceExceptions, but so what? Any element of the language can be a source of errors if used improperly. And what's the alternative? I suppose instead of saying this: Customer c = Customer.GetByLastName("Goodman"); // returns null if not found if (c != null) { Console.WriteLine(c.FirstName + " " + c.LastName + " is awesome!"); } else { Console.WriteLine("There was no customer named Goodman. How lame!"); } You could say this: if (Customer.ExistsWithLastName("Goodman")) { Customer c = Customer.GetByLastName("Goodman") // throws error if not found Console.WriteLine(c.FirstName + " " + c.LastName + " is awesome!"); } else { Console.WriteLine("There was no customer named Goodman. How lame!"); } But how is that better? Either way, if you forget to check that the customer exists, you get an exception. I suppose that a CustomerNotFoundException is a bit easier to debug than a NullReferenceException by virtue of being more descriptive. Is that all there is to it?

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• Returning a local object from a function

  - by pocoa

  Is this the right way to return an object from a function? Car getCar(string model, int year) { Car c(model, year); return c; } void displayCar(Car &car) { cout << car.getModel() << ", " << car.getYear() << endl; } displayCar(getCar("Honda", 1999)); I'm getting an error, "taking address of temporary". Should I use this way: Car &getCar(string model, int year) { Car c(model, year); return c; }

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• PHP Value Object auto create

  - by JonoB

  Assume that I have a class value object defined in php, where each variable in the class is defined. Something like: class UserVO { public $id; public $name; } I now have a function in another class, which is expecting an array ($data). function save_user($data) { //run code to save the user } How do I tell php that the $data parameter should be typed as a UserVO? I could then have code completion to do something like: $something = $data->id; //typed as UserVO.id $else = $data->name; //typed as UserVO.name I'm guessing something like the following, but this obviously doesnt work $my_var = $data as new userVO();

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• How to replace an object in an NSMutableArray at a given index with a new object

  - by shakeelw

  Hi guys. I have an NSMutableArray object(retained, synthesized as all) that is initiated just fine and I can easily add objects to it using the 'addObject:' method. But if I want to replace an object at a certain index with a new one in that NSMutableArray, it doesn't work. For example: ClassA.h @interface ClassA : NSObject { NSMutableArray *list; } @property (nonatomic, copy, readwrite) NSMutableArray *list; end ClassA.m import "ClassA.h" @implementation ClassA @synthesize list; (id)init { [super init]; NSMutableArray *localList = [[NSMutableArray alloc] init]; self.list = localList; [localList release]; //Add initial data [list addObject:@"Hello "]; [list addObject:@"World"]; } // Custom set accessor to ensure the new list is mutable (void)setList:(NSMutableArray *)newList { if (list != newList) { [list release]; list = [newList mutableCopy]; } } -(void)updateTitle:(NSString *)newTitle:(NSString *)theIndex { int i = [theIndex intValue]-1; [self.list replaceObjectAtIndex:i withObject:newTitle]; NSLog((NSString *)[self.list objectAtIndex:i]); // gives the correct output } However, the change remains true only inside the method. from any other method, the NSLog((NSString *)[self.list objectAtIndex:i]); gives the same old value. How can I actually get the old object replaced with the new one at a specific index so that the change can be noticed from within any other method as well. I even modified the method like this, but the result is the same: -(void)updateTitle:(NSString *)newTitle:(NSString *)theIndex { int i = [theIndex intValue]-1; NSMutableArray *localList = [[NSMutableArray alloc] init]; localList = [localList mutableCopy]; for(int j = 0; j < [list count]; j++) { if(j == i) { [localList addObject:newTitle]; NSLog(@"j == 1"); NSLog([NSString stringWithFormat:@"%d", j]); } else { [localList addObject:(NSString *)[self.list objectAtIndex:j]]; } } [self.list release]; //self.list = [localList mutableCopy]; [self setList:localList]; [localList release]; } Please help out guys :)

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• Output of System.out.println(object)

  - by Shaarad Dalvi

  I want to know what exactly the output tells when I do the following : class data { int a=5; } class main { public static void main(String[] args) { data dObj=new data(); System.out.println(dObj); } } I know it gives something related to object as the output in my case is data@1ae73783. I guess the '1ae73783' is a hex number. I also did some work around and printed System.out.println(dObj.hashCode()); I got number 415360643. I got an integer value. I don't know what hashCode() returns, still out of curiosity, when I converted 1ae73783 to decimal, I got 415360643! That's why I am curious that what exactly is this number?? Is this some memory location of Java's sandbox or some other thing? Any light on this matter will be helpful..thanks! :)

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• How to print object data in javascript

  - by rxzhang

  I have the following object data: var response = { "response": { "numFound": 7945, "docs": [{ "description": "target", "url": "target", "id": "269653", "score": 6.9186745 }, { "description": "Target Kent", "url": "Target_Kent", "id": "37275", "score": 4.3241715 }] }, "highlighting": { "269653": { "description": ["<em>target</em>"] }, "37275": { "description": ["<em>Target</em> Kent"] } } }; I can use response.response.docs[0].description to print out "target". But I don't know how to print out "<em>target</em>". Thanks.

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• storing huge amount of records into classic asp cache object is SLOW

  - by aspm

  we have some nasty legacy asp that is performing like a dog and i narrowed it down to because we are trying to store 15K+ records into the application cache object. but that's not the killer. before it stores it, it converts the ADO stream to XML then stores it. this conversion of the huge record set to XML spikes the CPU and causes all kinds of havoc on users when it's happening. and unfortunately we do this XML conversion to read the cache a lot, causing site wide performance problems. i don't have the resources to convert everything to .net. so that's out. but i need to obviously use caching, but int his case the caching is hurting instead of helping. is there a more effecient way to store this data instead of doing this xml conversion to/from every time we read/update the cache?

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