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  • Inheritance vs specific types in Financial Modelling for cashflows

    - by BlueTrin
    Hello, I have to program some financial applications where I have to represent a schedule of flows. The flows can be of 3 types: - fee flow (just a lump payment at some date) - floating rate flow (the flow is dependant of an interest rate to be determined at a later date) - fixed rate flow (the flow is dependant of an interest rate determined when the deal is done) I need to keep the whole information and I need to represent a schedule of these flows. Originally I wanted to use inheritance and create three classes FeeFlow, FloatingFlow, FixedFlow all inheriting from ICashFlow and implement some method GetFlowType() returning an enum then I could dynamic_cast the object to the correct type. That would allow me to have only one vector to represent my schedule. What do you think of this design, should I rather use three vectors vector, vector and vector to avoid the dynamic casts ?

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  • Inheritance in kohana

    - by Binaryrespawn
    Hi all, I have recently started to use Kohana and I know inheritance is in infancy stages at the moment. The work around is using a $_has_one annotation on the child class model. In may case i have "page" as the parent of "article". I have something like, protected $_has_one = array('mypage'=>array('model'=>'page', 'foreign_key'=>'id')); In my controller, I have an action which queries the database. In this query I am trying to access fields form the parent of "article" which is the "page". $n->articles=ORM::factory('article')->where('expires','=',0) ->where('articledate','<',date('y-m-d')) ->where('expirydate','>',date('y-m-d')) ->where('mypage->status','=','PUBLISHED') ->order_by('articledate','desc') ->find_all(); The status column resides in the page table and my query is generating an error to the effect of "cannot find status", clearly because it belongs to the parent. Any ideas ?

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  • Template inheritance: X is not a template

    - by user2923917
    I am trying to build a inheritance-structure which looks like: Base - template Grandpa - template Father class Base {}; template <int x> class Grandpa: public Base {}; template <int x> class Father: public Grandpa<x> {}; However, the compiler complains when compiling Father, that Grandpa is not a template. I guess it is just some synthatic issue, however everything I've tried so far led to even more compiler complaints ;) Any idea whats wrong?

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  • how to implement inheritance in hibernate ??

    - by user359057
    Hi guys i am working in a web application. I have a entities as BaseEntity --Which contains user login info like createdBy,createdTime,EditedBy,editedTime Employee -- which contains employee information like name,address,etc... RegularEmployee --which contains salary ,bonus tht kind of fields and ContactEmployee -- which contains HourlyRate,contactPeriod etc.... My inheritance structure is BaseEntity <--- Employee <---- RegularEmployee (i.e. Employee extends BaseEntity and RegularEmployee extends Employee ContractEmployee also extend Employee Class ). How to design database structure in this case considering all the tables have id and version fields (all tables should at least have these two fields).

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  • [C++] Simple inheritance question

    - by xbonez
    I was going over some sample questions for an upcoming test, and this question is totally confusing me. Any help would be appreciated. Consider the following code: class GraduateStudent : public Student { ... }; If the word "public" is omitted, GraduateStudent uses private inheritance, which means which of the following? GraduateStudent objects may not use methods of Student. GraduateStudent does not have access to private objects of Student. No method of GraduateStudent may call a method of Student. Only const methods of GraduateStudent can call methods of Student.

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  • UITableView: Mixing static and dynamic cells

    - by AlexR
    I am trying to mix dynamic and static cells in a grouped table view: I would like to get two sections with static cells at the top followed by a section of dynamic cells (please refer to the screenshot below). I have set the table view contents to static cells. I designed the static cells in Interface Builder and gave them identifiers related to their section and row: "section0static0", "section0static1", "section1static0" and "section1static1". I named the dynamic cell "section2dynamic". My delegate methods, in which I am trying to return the correct cell identifier (static or dynamic) are as follows: - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { switch (section) { case 0: return 2; break; case 1: return 2; break; case 2: return 0; break; default: break; } return 0; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @""; if (indexPath.section <= 1) CellIdentifier = [NSString stringWithFormat:@"section%istatic%i",indexPath.section,indexPath.row]; else CellIdentifier = [NSString stringWithFormat:@"section%idynamic",indexPath.section]; UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; return cell; } Edit Based on AppleFreak's advice I have changed my code as follows: - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { static NSString *CellIdentifier = @"Cell"; UITableViewCell *cell; if (indexPath.section <= 1) { // section <= 1 indicates static cells cell = [super tableView:tableView cellForRowAtIndexPath:indexPath]; } else { // section > 1 indicates dynamic cells CellIdentifier = [NSString stringWithFormat:@"section%idynamic",indexPath.section]; cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath]; } return cell; } However, my app crashes with error message Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:' for section 0 and row 0. The cell returned from cell = [super tableView:tableView cellForRowAtIndexPath:indexPath] for section 0 and row 0 is nil. What is wrong with my code? Could there be any problems with my outlets? I haven't set any outlets because I am subclassing UITableViewController and supposedly do not any outlets for tableview to be set (?). Any suggestions on how to better do it?

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  • Can YAML have inheritance?

    - by Jason
    This question involves a lot of symfony but it should be easy enough for someone to follow who only knows YAML and not symfony. My symfony models come from a three-step process: First, I create the tables in MySQL. Second, I run a symfony command (symfony doctrine:build-schema) to convert my table structure into a YAML file. Third, I run another symfony command (symfony doctrine:build-model) to convert the YAML file into PHP code. Here's the problem: there are some tables in the database that I don't want to end up in my symfony code. For example, let's say I have two tables: one called my_table and another called wordpress. The YAML file I end up with might look like this: MyTable: connection: doctrine tableName: my_table Wordpress: connection: doctrine tableName: wordpress That's great except the wordpress table has nothing to do with my symfony models. The result is that every single time I make a change to my database and generate this YAML file, I have to manually remove wordpress. It's annoying! I'd like to be able to create a file called baseConfig.php or something that looks like this: $config = array( 'MyTable' => array( 'connection' => 'doctrine', 'tableName' => 'my_table', ), 'Wordpress' => array( 'connection' => 'doctrine', 'tableName' => 'wordpress', ), ); And then I could have a separate file called config.php or something where I could make modifications to the base config: unset($config['Wordpress']); So my question is: is there any way to convert YAML into executable PHP code (as opposed to load YAML INTO PHP code like what sfYaml::load() does) to achieve this sort of thing? Or is there maybe some other way to achieve YAML inheritance? Thanks, Jason

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  • Inheritance using prototype / "new"

    - by mikkol
    Hi I'm new in Javascript OO and want to know more about about inheritance. Hope you can provide some advice! I see this great post: How to "properly" create a custom object in JavaScript? which talks about how a class is inherited as I see in other websites, ex.: function man(x) { this.x = x; this.y = 2; } man.prototype.name = "man"; man.prototype.two = function() { this.y = "two"; } function shawn() { man.apply(this, arguments); }; shawn.prototype = new man; The above post claims that in order not to call "man"'s constructor while inheriting, one can use a helper like this instead: function subclassOf(base) { _subclassOf.prototype= base.prototype; return new _subclassOf(); } function _subclassOf() {}; shawn.prototype = subclassOf(man); While I understand its intention, I don't see why we can't call shawn.prototype = man.prototype; I see it works exactly the same. Or is there something I'm missing? Thanks in advance!

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  • System.AccessViolationException when using TPT inheritance in Entity Framework CTP5

    - by Ben
    Hi, I'm using TPT inheritance in EF CTP5 with SQL CE 4. I have an abstract base class "Widget" with common properties like "Title". I can successfully save concrete Widget implementations e.g. "TwitterWidget". However, I have a problem retrieving all widgets (or rather ALL widget implementations). My repository exposes the following: public IQueryable<Widget> GetAll(); This effectively returns the IDbSet from the DbContext. The following queries work fine: repo.GetAll().ToList(); repo.GetAll().Where(w => w.Title == "Test").ToList(); repo.GetAll().SingleOrDefault(w => w.Title == "Test"); repo.GetAll().Where(w => w.Title == "Test").OrderBy(x => x.Title).ToList(); However, if I write the following query: repo.GetAll().OrderBy(w => w.Title); I get the following error: Test 'PlanetCloud.Portfolio.Tests.Data.PersistenceTestFixture.Can_get_widgets' failed: System.AccessViolationException : Attempted to read or write protected memory. This is often an indication that other memory is corrupt. at System.Data.SqlServerCe.NativeMethodsHelper.GetValues(IntPtr pSeCursor, Int32 seGetColumn, IntPtr prgBinding, Int32 cDbBinding, IntPtr pData, IntPtr pError) at System.Data.SqlServerCe.NativeMethods.GetValues(IntPtr pSeCursor, Int32 seGetColumn, IntPtr prgBinding, Int32 cDbBinding, IntPtr pData, IntPtr pError) at System.Data.SqlServerCe.SqlCeDataReader.FetchValue(Int32 index) at System.Data.SqlServerCe.SqlCeDataReader.IsDBNull(Int32 ordinal) at lambda_method(Closure , Shaper ) at System.Data.Common.Internal.Materialization.Shaper.HandleEntityAppendOnly[TEntity](Func`2 constructEntityDelegate, EntityKey entityKey, EntitySet entitySet) at lambda_method(Closure , Shaper ) at System.Data.Common.Internal.Materialization.Coordinator`1.ReadNextElement(Shaper shaper) at System.Data.Common.Internal.Materialization.Shaper`1.SimpleEnumerator.MoveNext() at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) However, I can execute the following query without problems: var widgets = repo.GetAll().OfType<Widget>().OrderBy(w => w.Title).ToList(); So if I specify the type as the base class prior to my orderby clause it works. The question is why?

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  • Duplicate column name by JPA with @ElementCollection and @Inheritance

    - by gerry
    I've created the following scenario: @javax.persistence.Entity @Inheritance(strategy = InheritanceType.TABLE_PER_CLASS) public class MyEntity implements Serializable{ @Id @GeneratedValue protected Long id; ... @ElementCollection @CollectionTable(name="ENTITY_PARAMS") @MapKeyColumn (name = "ENTITY_KEY") @Column(name = "ENTITY_VALUE") protected Map<String, String> parameters; ... } As well as: @javax.persistence.Entity public class Sensor extends MyEntity{ @Id @GeneratedValue protected Long id; ... // so here "protected Map<String, String> parameters;" is inherited !!!! ... } So running this example, no tables are created and i get the following message: WARNUNG: Got SQLException executing statement "CREATE TABLE ENTITY_PARAMS (Entity_ID BIGINT NOT NULL, ENTITY_VALUE VARCHAR(255), ENTITY_KEY VARCHAR(255), Sensor_ID BIGINT NOT NULL, ENTITY_VALUE VARCHAR(255))": com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Duplicate column name 'ENTITY_VALUE' I also tried overriding the attributes on the Sensor class... @AttributeOverrides({ @AttributeOverride(name = "ENTITY_KEY", column = @Column(name = "SENSOR_KEY")), @AttributeOverride(name = "ENTITY_VALUE", column = @Column(name = "SENSOR_VALUE")) }) ... but the same error. Can anybody help me?

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  • C++ struct, public data members and inheritance

    - by Marius
    Is it ok to have public data members in a C++ class/struct in certain particular situations? How would that go along with inheritance? I've read opinions on the matter, some stated already here http://stackoverflow.com/questions/952907/practices-on-when-to-implement-accessors-on-private-member-variables-rather-than http://stackoverflow.com/questions/670958/accessors-vs-public-members or in books/articles (Stroustrup, Meyers) but I'm still a little bit in the shade. I have some configuration blocks that I read from a file (integers, bools, floats) and I need to place them into a structure for later use. I don't want to expose these externally just use them inside another class (I actually do want to pass these config parameters to another class but don't want to expose them through a public API). The fact is that I have many such config parameters (15 or so) and writing getters and setters seems an unnecessary overhead. Also I have more than one configuration block and these are sharing some of the parameters. Making a struct with all the data members public and then subclassing does not feel right. What's the best way to tackle that situation? Does making a big struct to cover all parameters provide an acceptable compromise (I would have to leave some of these set to their default values for blocks that do not use them)?

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  • Enums and inheritance

    - by devoured elysium
    I will use (again) the following class hierarchy: Event and all the following classes inherit from Event: SportEventType1 SportEventType2 SportEventType3 SportEventType4 I have originally designed the Event class like this: public abstract class Event { public abstract EventType EventType { get; } public DateTime Time { get; protected set; } protected Event(DateTime time) { Time = time; } } with EventType being defined as: public enum EventType { Sport1, Sport2, Sport3, Sport4 } The original idea would be that each SportEventTypeX class would set its correct EventType. Now that I think of it, I think this approach is totally incorrect for two reasons: If I want to later add a new SportEventType class I will have to modify the enum If I later decide to remove one SportEventType that I feel I won't use I'm also in big trouble with the enum. I have a class variable in the Event class that makes, afterall, assumptions about the kind of classes that will inherit from it, which kinda defeats the purpose of inheritance. How would you solve this kind of situation? Define in the Event class an abstract "Description" property, having each child class implement it? Having an Attribute(Annotation in Java!) set its Description variable instead? What would be the pros/cons of having a class variable instead of attribute/annotation in this case? Is there any other more elegant solution out there? Thanks

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  • Can I make my drives visible and change their partition type without losing my data?

    - by user165408
    I have made a lot of mistakes and now I cannot see my hard disk nor I can start my operating system on my laptop. All my passwords and important files on my hdd without any backup. I followed this course of action Changed my hard disk partitions to dynamic just for getting 5th partition. (1st mistake) Decreased partitions to 4 again. Backed up operating system from 4th to 3rd partition with Norton Ghost. Booted from a live CD for Windows XP. Formatted 4th partition and moved my all important data from 1st and 2nd partitions to the 4th partition. Deleted 1st and 2nd partitions and got 1 partition from half of empty space. So I have just 3 partitions and empty space between 1st and 2nd partitions. Tried to install Windows 8 to the first partition but it did not allow because it is dynamic. Also it did not allow to install to other partitions. Tried to install Windows XP to the 1st partition but it said if I continue I cannot use other drivers. Therefore I escaped from installing it. Booted from the Windows XP live CD then increased 1st partiton to less than 400mb of empty space. Therefore I thought it will be adjacent but it was shown as 2 partitions. In my computer I see just 3 drivers. Using Norton Ghost I recovered my OS to the 1st partition. (2nd mistake it was on 4th partition originally) Booted from a Windows XP live CD I tried to install bcdedit to the Windows XP live CD but it did not work. Then I tried to install EaseUS Partition Master Home Edition. It was installed with errors then I start it and it showed me an error like there is no hard disk. I looked to my PC and my drivers were not there. Booted from the Norton Ghost CD and it did not show me my drivers either, but before I was able to see them. I checked numbers of partition shown by the Norton Ghost utility and they are still have same numbers so I have to see my drivers but I cannot see them now. My hard disk is shown as extarnal dynamic now so I cannot see any drive in my PC in the live Windows XP. There are two options; first one is import extarnal disk and second one is convert disk to basic. Will they delete my data? I fear booting from CDs like Windows XP live CD, Norton Ghost CD, and the operating system CD/DVD, because they may overwrite a few MB their data to my data. These recover tools are already exist in Windows XP live CD by The Ultimate Boot CD for Windows. Can any of them help me? CompuAppa SwissKnife V3 DBXtract Disk Investigator Fab's AutoBackup 2.0 FileRecovery Floppy Repair Free Undelete Handy Recovery Recovery Manager Restorastion Restorastion Help File by UBCD4Win UnChk Unstoppable Copier Finally How can I make it so that my drives are visible again without losing my data? How can I convert my dynamic partitions to basic without losing my data?

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  • Adding custom methods to a subclassed NSManagedObject

    - by CJ
    I have a Core Data model where I have an entity A, which is an abstract. Entities B, C, and D inherit from entity A. There are several properties defined in entity A which are used by B, C, and D. I would like to leverage this inheritance in my model code. In addition to properties, I am wondering if I can add methods to entity A, which are implemented in it's sub-entities. For example: I add a method to the interface for entity A which returns a value and takes one argument I add implementations of this method to A, B, C, D Then, I call executeFetchRequest: to retrieve all instances of B I call the method on the objects retrieved, which should call the implementation of the method contained in B's implementation I have tried this, but when calling the method, I receive: [NSManagedObject methodName:]: unrecognized selector sent to instance I presume this is because the objects returned by executeFetchRequest: are proxy objects of some sort. Is there any way to leverage inheritance using subclassed NSManagedObjects? I would really like to be able to do this, otherwise my model code would be responsible for determining what type of NSManagedObject it's dealing with and perform special logic according to the type, which is undesirable. Any help is appreciated, thanks in advance.

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  • constructor function's object literal returns toString() method but no other method

    - by JohnMerlino
    I'm very confused with javascript methods defined in objects and the "this" keyword. In the below example, the toString() method is invoked when Mammal object instantiated: function Mammal(name){ this.name=name; this.toString = function(){ return '[Mammal "'+this.name+'"]'; } } var someAnimal = new Mammal('Mr. Biggles'); alert('someAnimal is '+someAnimal); Despite the fact that the toString() method is not invoked on the object someAnimal like this: alert('someAnimal is '+someAnimal.toString()); It still returns 'someAnimal is [Mammal "Mr. Biggles"]' . That doesn't make sense to me because the toString() function is not being called anywhere. Then to add even more confusion, if I change the toString() method to a method I make up such as random(): function Mammal(name){ this.name=name; this.random = function(){ return Math.floor(Math.random() * 15); } } var someAnimal = new Mammal('Mr. Biggles'); alert(someAnimal); It completely ignores the random method (despite the fact that it is defined the same way was the toString() method was) and returns: [object object] Another issue I'm having trouble understanding with inheritance is the value of "this". For example, in the below example function person(w,h){ width.width = w; width.height = h; } function man(w,h,s) { person.call(this, w, h); this.sex = s; } "this" keyword is being send to the person object clearly. However, does "this" refer to the subclass (man) or the super class (person) when the person object receives it? Thanks for clearing up any of the confusion I have with inheritance and object literals in javascript.

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  • Inereritance of clousure objects and overriding of methods

    - by bobikk
    I need to extend a class, which is encapsulated in a closure. This base class is following: var PageController = (function(){ // private static variable var _current_view; return function(request, new_view) { ... // priveleged public function, which has access to the _current_view this.execute = function() { alert("PageController::execute"); } } })();` Inheritance is realised using the following function: function extend(subClass, superClass){ var F = function(){ }; F.prototype = superClass.prototype; subClass.prototype = new F(); subClass.prototype.constructor = subClass; subClass.superclass = superClass.prototype; StartController.cache = ''; if (superClass.prototype.constructor == Object.prototype.constructor) { superClass.prototype.constructor = superClass; } } I subclass the PageController: var StartController = function(request){ // calling the constructor of the super class StartController.superclass.constructor.call(this, request, 'start-view'); } // extending the objects extend(StartController, PageController); // overriding the PageController::execute StartController.prototype.execute = function() { alert('StartController::execute'); } Inheritance is working. I can call every PageController's method from StartController's instance. However, method overriding doesn't work: var startCont = new StartController(); startCont.execute(); alerts "PageController::execute". How should I override this method?

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  • How to copy generically superclass instances to subclass instances?

    - by gerry
    Hi @all, I have a class hierarchy / inheritance like this: public class A { private String name; // with getters & setters public void doAWithName(){ ... } } public class B extends A { public void doBWithName(){ // a differnt implementation to what I do in class A } } public class C extends B { public void doCWithName(){ // a differnt implementation to what I do in class A and B } } So at one time there is a instance of class A with the initialized field "name". Later I want this instance of A get wrapped into instance of B or C. So the superclasses should be get wrapped with a subclass! How can I make this most efficent with respect to DRY? I've thought about a constructor that does some copying with the getters/setters. But in this case I have to repeat myself - and this doesn't respect anymore to my initial requirement of DRY! So, how can I warp A to B by just initializing B's new fields (with default values) and delegating the rest to a method in A (which knows more than B about which fields of A should be accessed...). In the same way: If A should be wrapped into C only a method in c should init C's 'new' fields, delegate to B's wrap method (which therefore inits B's 'new' fields in C) and at last B delegates to A which copies it's fields to the fields of C). So in the end I have a new instance of C which has the values of A wrapped (and some default init values to the fields which the inheritance hierarchy has added).

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  • Is `List<Dog>` a subclass of `List<Animal>`? Why aren't Java's generics implicitly polymorphic?

    - by froadie
    I'm a bit confused about how Java generics handle inheritance / polymorphism. Assume the following hierarchy - Animal (Parent) Dog - Cat (Children) So suppose I have a method doSomething(List<Animal> animals). By all the rules of inheritance and polymorphism, I would assume that a List<Dog> is a List<Animal> and a List<Cat> is a List<Animal> - and so either one could be passed to this method. Not so. If I want to achieve this behavior, I have to explicitly tell the method to accept a list of any subset of Animal by saying doSomething(List<? extends Animal> animals). I understand that this is Java's behavior. My question is why? Why is polymorphism generally implicit, but when it comes to generics it must be specified?

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  • C++ Implicit Conversion Operators

    - by Imbue
    I'm trying to find a nice inheritance solution in C++. I have a Rectangle class and a Square class. The Square class can't publicly inherit from Rectangle, because it cannot completely fulfill the rectangle's requirements. For example, a Rectangle can have it's width and height each set separately, and this of course is impossible with a Square. So, my dilemma. Square obviously will share a lot of code with Rectangle; they are quite similar. For examlpe, if I have a function like: bool IsPointInRectangle(const Rectangle& rect); it should work for a square too. In fact, I have a ton of such functions. So in making my Square class, I figured I would use private inheritance with a publicly accessible Rectangle conversion operator. So my square class looks like: class Square : private Rectangle { public: operator const Rectangle&() const; }; However, when I try to pass a Square to the IsPointInRectangle function, my compiler just complains that "Rectangle is an inaccessible base" in that context. I expect it to notice the Rectangle operator and use that instead. Is what I'm trying to do even possible? If this can't work I'm probably going to refactor part of Rectangle into MutableRectangle class. Thanks.

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  • Firefox add-on development: Register global dynamic custom keyboard shortcuts

    - by dezwart
    I have been tasked with developing a Firefox add-on that is capable of registering global keyboard shortcuts (ones that will work throughout all areas of Firefox) that will open up the side-bar and execute an XMLRPC request based on previously recorded input. The idea here is that there will be many potential XMLRPC requests that the user will want to execute via a keyboard shortcut. Currently, the add-on is capable of handling pre-defined static keyboard shortcuts via the Firefox overlay. What I would like to achieve, is to allow the user to register their own dynamic custom keyboard shortcut. There is an add-on that currently has some of this functionality, called Keyconfig. I'm not keen on having to ask users to install a second add-on to define their own shortcuts. It also seems that using the dynamic keyboard shortcut registration method in Keyconfig would require the user to close all Firefox windows before the dynamic shortcut is made available. What I would like to know is: Is an XPCOM component the best way to register dynamic keyboard shortcuts from within a Firefox add-on? Is there a way to register the keyboard shortcut so that it is immediately available to all Firefox windows, without having to close the windows beforehand?

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  • Why aren't Java's generics implicitly polymorphic?

    - by froadie
    I'm a bit confused about how Java generics handle inheritance / polymorphism. Assume the following hierarchy - Animal (Parent) Dog - Cat (Children) So suppose I have a method doSomething(List<Animal> animals). By all the rules of inheritance and polymorphism, I would assume that a List<Dog> is a List<Animal> and a List<Cat> is a List<Animal> - and so either one could be passed to this method. Not so. If I want to achieve this behavior, I have to explicitly tell the method to accept a list of any subset of Animal by saying doSomething(List<? extends Animal> animals). I understand that this is Java's behavior. My question is why? Why is polymorphism generally implicit, but when it comes to generics it must be specified?

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  • Using JAXB to unmarshal/marshal a List<String> - Inheritance

    - by gerry
    I've build the following case. An interface for all JAXBLists: public interface JaxbList<T> { public abstract List<T> getList(); } And an base implementation: @XmlRootElement(name="list") public class JaxbBaseList<T> implements JaxbList<T>{ protected List<T> list; public JaxbBaseList(){} public JaxbBaseList(List<T> list){ this.list=list; } @XmlElement(name="item" ) public List<T> getList(){ return list; } } As well as an implementation for a list of URIs: @XmlRootElement(name="uris") public class JaxbUriList2 extends JaxbBaseList<String> { public JaxbUriList2() { super(); } public JaxbUriList2(List<String> list){ super(list); } @Override @XmlElement(name="uri") public List<String> getList() { return list; } } And I'm using the List in the following way: public JaxbList<String> init(@QueryParam("amount") int amount){ List<String> entityList = new Vector<String>(); ... enityList.add("http://uri"); ... return new JaxbUriList2(entityList); } I thought the output should be: <uris> <uri> http://uri </uri> ... </uris> But it is something like this: <uris> <item xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xs="http://www.w3.org/2001/XMLSchema" xsi:type="xs:string"> http://uri </item> ... <uri> http://uri </uri> ... </uris> I think it has something to do with the inheritance, but I don't get it... What's the problem? - How can I fix it? Thanks in advance!

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  • Handling Model Inheritance in ASP.NET MVC2 & NHibernate

    - by enth
    I've gotten myself stuck on how to handle inheritance in my model when it comes to my controllers/views. Basic Model: public class Procedure : Entity { public Procedure() { } public int Id { get; set; } public DateTime ProcedureDate { get; set; } public ProcedureType Type { get; set; } } public ProcedureA : Procedure { public double VariableA { get; set; } public int VariableB { get; set; } public int Total { get; set; } } public ProcedureB : Procedure { public int Score { get; set; } } etc... many of different procedures eventually. So, I do things like list all the procedures: public class ProcedureController : Controller { public virtual ActionResult List() { IEnumerable<Procedure> procedures = _repository.GetAll(); return View(procedures); } } but now I'm kinda stuck. Basically, from the list page, I need to link to pages where the specific subclass details can be viewed/edited and I'm not sure what the best strategy is. I thought I could add an action on the ProcedureController that would conjure up the right subclass by dynamically figuring out what repository to use and loading the subclass to pass to the view. I had to store the class in the ProcedureType object. I had to create/implement a non-generic IRepository since I can't dynamically cast to a generic one. public virtual ActionResult Details(int procedureID) { Procedure procedure = _repository.GetById(procedureID, false); string className = procedure.Type.Class; Type type = Type.GetType(className, true); Type repositoryType = typeof (IRepository<>).MakeGenericType(type); var repository = (IRepository)DependencyRegistrar.Resolve(repositoryType); Entity procedure = repository.GetById(procedureID, false); return View(procedure); } I haven't even started sorting out how the view is going to determine which partial to load to display the subclass details. I'm wondering if this is a good approach? This makes determining the URL easy. It makes reusing the Procedure display code easy. Another approach is specific controllers for each subclass. It simplifies the controller code, but also means many simple controllers for the many procedure subclasses. Can work out the shared Procedure details with a partial view. How to get to construct the URL to get to the controller/action in the first place? Time to not think about it. Hopefully someone can show me the light. Thanks in advance.

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  • Fluent | Nhibernate multiple inheritance mapping?

    - by Broken Pipe
    I'm trying to map this classes: public interface IBusinessObject { Guid Id { get; set; } } public class Product { public virtual Guid Id { get; set; } public virtual int ProductTypeId { get; set; } } public class ProductWeSell : Product, IBusinessObject { } public class ProductWeDontSell : Product { } Using this Fluent mapping code: public class IBusinessObjectMap : ClassMap<IBusinessObject> { public IBusinessObjectMap() { Id(t => t.Id).GeneratedBy.Guid(); Table("BusinessObject"); } } public class ProductMap : ClassMap<Product> { public ProductMap() { Id(t => t.Id); DiscriminateSubClassesOnColumn("ProductTypeId", "null").Nullable(); } } public class ProductWeSellMap : SubclassMap<ProductWeSell> { public ProductWeSellMap() { DiscriminatorValue(1); KeyColumn("Id"); } } public class ProductWeDontSellMap : SubclassMap<ProductWeDontSell> { public ProductWeDontSellMap() { DiscriminatorValue(2); KeyColumn("Id"); } } But I get {"Duplicate class/entity mapping ProductWeSell"} error. And if we take a look at generated HBM, indeed it's duplicated, but i have no idea how to write this mapping without duplicating it if it's possible at all. Produced hbm: <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> <class xmlns="urn:nhibernate-mapping-2.2" name="IBusinessObject" table="BusinessObject"> <joined-subclass name="ProductWeSell" table="ProductWeSell"/> </class> </hibernate-mapping> <hibernate-mapping xmlns="urn:nhibernate-mapping-2.2"> <class xmlns="urn:nhibernate-mapping-2.2" discriminator-value="null" name="Product" table="Product"> <discriminator type="String"> <column name="ProductTypeId" not-null="false" /> </discriminator> <subclass name="ProductWeDontSell" discriminator-value="2" /> <subclass name="ProductWeSell" discriminator-value="1" /> </class> </hibernate-mapping> So far I was unable to figure out how to map this using fluent Nhibernate (i haven't tried mapping this using hmb files). Any help appreciated Fluent or HBM files. The thing I'm trying to solve look identical to this topic: NHibernate inheritance mapping question

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