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• Trying to understand MVC Models, Advice?

  - by Tyler

  I am writing my own MVC for the purpose of learning it. I have pretty much everything "down-pat" and my main stuff written besides models due to some trouble understanding them and lack of viable examples. Now, I've been told a model should reprecent a single row, someone told me, your model class should on update/insert and delete rows, anything that involves fetching a single or multiple rows - a "finder" class should be used. So... a) what is a finder class, b) how do I implement it in a useage example, c) Is what I've been told about models correct or is there a better way than "finders"? Advice is much appricated :)

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• Security in API authentication

  - by Carlos

  We are in the process of revamping our server side API, and we need to manage security. Our current model requires that a credentials object (containing user, password, and pin) be included in each method invocation. Our development team, however, has decided that we should have session objects instead (which is fine by me), but the new credentials are just a GUID. This is very different from what I've seen in other APIs in our industry, so I'm a bit concerned about how secure the new model will be. I asked them if they had analyzed both alternatives, and they said they haven't. Does anyone know if there're any clear advantages, disadvantages, risks, etc. of using a set of credentials versus just one element (complex as it may be)? PS: the communication channel would be secure in either case, and it's separate from this particular topic

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• Is there an easier way to typecast with unknown types?

  - by Adam S

  Hi all. I am writing a function to recurse my XAML and add all the controls to a hashtable, with their names being the keys. Unfortunately it seems like I have to go through and list every possible type: void Recurse_Controls(object start) { string start_type = start.GetType().ToString(); if (start_type == "StackPanel") { ControlsByName.Add(((StackPanel)start).Name, start); foreach (object item in ((StackPanel)start).Children) { Recurse_Controls(item); } } if (start_type == "Grid") { ControlsByName.Add(((Grid)start).Name, start); foreach (object item in ((Grid)start).Children) { Recurse_Controls(item); } } } Is there a simpler way of doing this?

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• How To Get Type Info Without Using Generics?

  - by DaveDev

  Hi Guys I have an object obj that is passed into a helper method. public static MyTagGenerateTag<T>(this HtmlHelper htmlHelper, T obj /*, ... */) { Type t = typeof(T); foreach (PropertyInfo prop in t.GetProperties()) { object propValue = prop.GetValue(obj, null); string stringValue = propValue.ToString(); dictionary.Add(prop.Name, stringValue); } // implement GenerateTag } I've been told this is not a correct use of generics. Can somebody tell me if I can achieve the same result without specifying a generic type? If so, how? I would probably change the signature so it'd be like: public static MyTag GenerateTag(this HtmlHelper htmlHelper, object obj /*, ... */) { Type t = typeof(obj); // implement GenerateTag } but Type t = typeof(obj); is impossible. Any suggestions? Thanks Dave

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• Expand in linq not loading inner data collections from service.

  - by Kit

  I am seeing odd behavior with service queries! I am using MVVM pattern for a silverlight 3 app on 3.5 framework and Dataservices 1.5. The following code eager loads correctly the parent object and the child heirarchy perfectly IF and ONLY IF I am preloading the data. But I would like to fetch a different set of the parent object (and its child heirarchy) on different button clicks. What I am seeing is that on button click, only the parent object is retrieved, and the child heirarchy contains nothing. Any suggestions? Any ideas how to tackle this? Thanks all. The method: DataServiceQuery serviceQuery = (DataServiceQuery)(from m1 in dbEntities.gis_Region.Expand("gis_RegionValue/gis_Measure") where m1.RegionGuid == new Guid(regionGuid) select m1); serviceQuery.BeginExecute(GetRegionDetailAsyncResult, serviceQuery); The wired Async Result: DataServiceQuery query = (DataServiceQuery)result.AsyncState; gis_Region region = query.EndExecute(result).First();

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• Creating a triple store query using SQL - how to find all triples that have a common predicate and o

  - by Ankur

  I have a database that acts like a triple store, except that it is just a simple MySQL database. I want to select all triples that have a common predicate and object. Info about RDF and triples I can't seem to work out the SQL. If I had just a single predicate and object to match I would do: select TRIPLE from TRIPLES where PREDICATE="predicateName" and OBJECT="objectName" But if I have a list (HashMap) of many pairs of (predicateName,objectName) I am not sure what I need to do. Please let me know if I need to provide more info, I am not sure that I have made this quite clear, but I am wary of providing too much info and confusing the issue.

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• OWL inferencing question

  - by user439170

  I am using the Jena semantic web framework version 2.6.3. I have code that creates a model with owl inferencing and then adds the following triples: [:bnode-3 rdf:type owl:Restriction] [:bnode-3 owl:onProperty :offspringOf] [:bnode-3 owl:someValuesFrom :Person] [:bnode-3 rdfs:subClassOf :Person] bnode-3 is supposed to be a restriction class which, for example, would contain :joe if :bob is a :Person and the following triple were asserted: [:joe :offspringOf :bob]. Then, since the restriction class is a subclass of Person, :joe would also be a person. And, in fact, this works. Whats confusing to me is that after I assert just the 4 triples at the top of this post, the inferencer creates a blank node which is a Person. In other words, the following triple is now in the model: [_:b0 rdf:type :Person] I don't understand why it would do this. Any help in understanding this would be greatly appreciated. Thanks. Kent.

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• Why would the first call to a KVC setter have an NSTextField instance as the argument?

  - by Stephen

  If I have a NSTextField bound through an NSObjectController to a model object, I would expect the setter of the model object to be called with an NSString as the argument, but instead, I receive the instance of the control that I am bound too the first time I am called. - (NSString *)property { NSLog(@"returning property"); return property; } - (void)setProperty:(NSString *)string { NSLog(@"recieved %@", string) } - (id) init { if (self = [super init]) { property = [[NSString alloc] initWithString:@"value"]; } NSLog(@"property is %@",property"); return self; } (The program doesn't run if you try anything in setProperty, because it tries to send NSString messages to string - which might be an NSTextField.) Console Output: 2010-05-12 14:19:14.096 Trouble[13108:10b] property is enter value 2010-05-12 14:19:14.100 Trouble[13108:10b] recieved <NSTextField: 0x1025210> 2010-05-12 14:19:14.106 Trouble[13108:10b] returning property

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• where should i encode this html data in an asp.net mvc site

  - by ooo

  here is my view code: <%=Model.HtmlData %> here is my controller code: public ActionResult GetPage() { ContentPageViewModel vm = new ContentPageViewModel(); vm.HtmlData = _htmlPageRepository.Get("key"); return View(vm); } my repository class basically queries a database table that has the fields: id, pageName, htmlContent the .Get() method passes in a pageName (or key) and returns the htmlContent value. Right now i have just started this (haven't persisted anything to the db yet) so i am not doing any explicit encoding in my code now. What is the best practice for where i need to do encoding (in the model, the controller, the view ??)

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• Trying to get Package Version Information to display in an "About" message.

  - by user313135

  Hello, I have been struggling with getting the versionName for a running application from the PackageInfo Object type. I have constructed a Parcelable Interface with all of the fields associated with the PackageInfo Object type. The primary input for that interface method is a Parcel object. I cannot seem to figure out how to correctly associate these Parcelable, Parcel, and PackageInfo objects. Is there any sample code out there that I can look at? Doesn't seem like it should be that difficult but it seems to be stumping me. Thanks Jazz

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• asp.net mvc & jquery dialog: What approach do I take to add items to a dropdownlist/select list with

  - by Mark Redman

  Hi, I am new to MVC and have a grasp of the basic model, but still doing everything with postbacks etc. One aspect of the UI I want to build is to have a drop-down-list of items with a button to add an item to the database and refresh the list. Achieving this with WebForms was straight forward as everything was wrapped in UpdatePanels, but what is the best approach to achieve this using MVC? Part of the markup for the list and button look like this: <table> <tr> <td><%=Html.DropDownList("JobTitleSelectList", Model.JobTitleSelectList, "(select job title)", new { @class = "data-entry-field" })%></td> <td>&nbsp;</td> <td><a id="AddJobTitleDialogLink" href="javascript: addJobTitleDialog();" title="Add Job Title"><img id="AddJobTitleButtonImage" src="/Content/Images/Icons/16x16/PlusGrey.png" border="0" /></a></td> </tr> </table> The Dialog is a standard jquery Ui dialog, looks like this: <div id="SingleTextEntryDialog" style="display:none"> <table> <tr> <td>Name:</td> <td><input id="SingleTextEntryDialogText" type="text" size="25" /></td> </tr> </table> </div> I am guessing I need to put this into a UserControl / PartialView (are they the same thing?) Also with the strongly typed View how do I pass the Model or just the SelectList Property to the UserControl or is this not the case? Nor sure if there should be form in the dialog div? or how that is going to postback via ajax. Some examples show a lot of ajax code in the page something like: $.ajax({...}); I assume doing this using jquery is more code than asp.net webforms, but there is just more code to see doing a "View Source" on a page? Your comments appreciated.

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• More strict query yields more results?

  - by Mark

  I've got a query that looks like this affiliates = User.objects.annotate(referral_count=Count('referrals')).filter(referral_count__gt=0) But when I restrict it more by adding referrals__user__date_joined__gt=start_date to the filter, I get even higher referral counts. I'm trying to count the number of people a user has referred within a time period. The relevant model looks like this: class Profile(models.Model): user = models.ForeignKey(User, unique=True, related_name='profile') referred_by = models.ForeignKey(User, null=True, blank=True, related_name='referrals') In contrast, when I try it like this: affiliates = User.objects \ .exclude(referrals__user__date_joined__lte=sd, referrals__user__date_joined__gt=ed) \ .annotate(referral_count=Count('referrals')) \ .filter(referral_count__gt=0) The exclude statement seems to do nothing... the counts don't change (should be 0 if no referred users have joined within that time period, but it isn't).

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• Formatting Log File Messages

  - by Kumar

  This is about formatting the messages for logging so as to subsequently be able to parse them relatively easily esp. given the extensive logging required in financial apps Typically a line in the log file is of the form TimeStamp: Module/Function: where the log string contains whatever you choose, typically you'd have some key=value paradigm or even johnny5 key {value} etc. A regex search through the log file might easily pick up Module/Function but enforcing and maintaing consistency on the log string itself for every developer on the team is often a pain The logging api's are typically ILog.LogInfo(string text, params object[] args) ILog.LogWarning(string text, params object[] args) ILog.LogError(string text, params object[] args) Looking for opinions on better logging api's to format the log messages where a regex search can be performed for Module/Function = Basket/AddItem TokenA = Value1 and TokenB = Value2 etc. without going over every developer's every logging call

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• Using STI path with same controller

  - by TenJack

  I am using STI and am wondering, do I have to have a separate controller for each model? I have a situation where I only use the create and edit actions for one model in the STI relationship, but I get an 'undefined method' error if I try to do a form for. More specifically, I have two models that inherit from List: class RegularList < List class OtherList < List and I have a lists controller that handles these actions, but I only create new models with RegularList using forms. i.e. the only situation where I use a form_for to create a new List object is with RegularList. What I would like to do is something like: class ListsController < ApplicationController def new @list = RegularList.new end otherwise the route for creating a new list looks like regular_list/new but I would like it to just be list/new. Thoughts?

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• Django: Grouping by Dates and Servers

  - by TheLizardKing

  So I am trying to emulate google app's status page: http://www.google.com/appsstatus#hl=en but for backups for our own servers. Instead of service names on the left it'll be server names but the dates and hopefully the pagination will be there too. My models look incredibly similar to this: from django.db import models STATUS_CHOICES = ( ('UN', 'Unknown'), ('NI', 'No Issue'), ('IS', 'Issue'), ('NR', 'Not Running'), ) class Server(models.Model): name = models.CharField(max_length=32) def __unicode__(self): return self.name class Backup(models.Model): server = models.ForeignKey(Server) created = models.DateField(auto_now_add=True) modified = models.DateTimeField(auto_now=True) status = models.CharField(max_length=2, choices=STATUS_CHOICES, default='UN') issue = models.TextField(blank=True) def __unicode__(self): return u'%s: %s' % (self.server, self.get_status_display()) My issue is that I am having a hell of a time displaying the information I need. Everyday a little after midnight a cron job will run and add a row for each server for that day, defaulting on status unknown (UN). My backups.html: {% extends "base.html" %} {% block content %} <table> <tr> <th>Name</th> {% for server in servers %} <th>{{ created }}</th> </tr> <tr> <td>{{ server.name }}</td> {% for backup in server.backup_set.all %} <td>{{ backup.get_status_display }}</td> {% endfor %} </tr> {% endfor %} </table> {% endblock content %} This actually works but I do not know how to get the dates to show. Obviously {{ created }} doesn't do anything but the servers don't have create dates. Backups do and because it's a cron job there should only be X number of rows with any particular date (depending on how many servers we are following for that day). Summary I want to create a table, X being server names, Y being dates starting at today while all the cells being the status of a backup. The above model and template should hopefully give you an idea what my thought process but I am willing to alter anything. Basically I am create a fancy excel spreadsheet.

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• Keep a reference to an NSThread around and message its objects?

  - by RickiG

  Hi I am a bit uncertain on how to do this: I start a "worker-thread" that runs for the duration of my apps "life". [NSThread detachNewThreadSelector:@selector(updateModel) toTarget:self withObject:nil]; then - (void) updateModel { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; BackgroundUpdate *update = [[BackgroundUpdate alloc] initWithTimerInterval:5]; [[NSRunLoop currentRunLoop] run]; //keeps it going 'forever' [update release]; [pool release]; } Now the thread "wakes" up every 5 seconds(initWithTimerInterval) to see if there are any tasks it can do. All the tasks in the BackGroundUpdate Class are only time dependent for now. I would like to have a few that were "event dependent". e.g. I would like to call the Background Object from my main thread and tell it to "speedUp", "slowDown", "reset" or any method on the object. To do this I guess I need something like performSelectorOnThread but how to get a reference to the NSthread and the Background Object?

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• ASP.NET MVC Session across subdomains

  - by nccsbim071

  Hi, In my website i have implemented custom session values. In which, on log on i set the session value to some object. This object is used to extract user specific data from db. now the problem is If user logs in with : test1.somesite.com and logs off and again logs in with: test2.somesite.com that user is still receiving the data from object specific to test1.somesite.com. the point is whichever site user frist logs in with the second time if he logs in with anathor subdomain he is always getting the data from previous sub domain login. on log out from specific domain i cleared all the sessions(tried everything): by putting HttpContext.session["UserDetail"] = null;, HttpContext.Session.Abandon() and also HttpContext.Session.Clear(); but nothing seems to work any help please

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• Is there anyone out there that codes like I do?

  - by Jacob Relkin

  Hi, Some people have told me that my coding style is a lot different than theirs. I think I am somewhat neurotic when it comes to spacing and indenting though. Here's a snippet to show you what I mean: - ( void ) applicationDidFinishLaunching: ( UIApplication *) application { SomeObject *object = [ [ SomeObject alloc ] init ]; int x = 100 / 5; object.someInstanceVariable = ( ( 4 * x ) + rand() ); [ object someMethod ]; } Notice how I space out all of my brackets/parentheses, start curly braces on the same line, "my code has room to breathe", so to speak. So my questions are a) is this normal and b) What's your coding style?

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• python json_encode throws KeyError exception

  - by MattM

  In a unit test case that I am running, I get a KeyError exception on the 4th json object in the json text below. I went through the sub-objects and found that it was the "cpuid" object that is the offending object, but I am completely at a loss as to what is wrong with the formatting. response = self.app.post( '/machinestats', params=dict(record=self.json_encode([ {"type": "crash", "instance_id": "xxx", "version": "0.2.0", "build_id": "unknown", "crash_text": "Gah!"}, {"type": "machine_info", "machine_info": "I'm awesome.", "version": "0.2.0", "build_id": "unknown", "instance_id": "yyy"}, {"machine_info": "Soup", "crash_text": "boom!", "version": "0.2.0", "build_id": "unknown", "instance_id": "zzz", "type": "crash"}, {"build_id" : "unknown", "cpu_brand" : "intel", "cpu_count" : 4, "cpuid": { "00000000": {"eax" :123,"ebx" :456, "ecx" :789,"edx" :321}, "00000001": {"eax" :123,"ebx" :456, "ecx" :789,"edx" :321}}, "driver_installed" : True, "instance_id" : "yyy", "version" : "0.2.0", "machine_info" : "I'm awesome.", "os_version" : "linux", "physical_memory_mib" : 1024, "product_loaded" : True, "type" : "machine_info", "virtualization_advertised" : True} ])))

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• CakePHP: How can I change this find call to include all records that do not exist in the associated

  - by Stephen

  I have a few tables with the following relationships: Company hasMany Jobs, Employees, and Trucks, Users I've got all my foreign keys set up properly, along with the tables' Models, Controllers, and Views. Originally, the Jobs table had a boolean field called "assigned". The following find operation (from the JobsController) successfully returns all employees, all trucks, and any jobs that are not assigned and fall on a certain day for a single company (without returning users by utilizing the containable behavior): $this->set('resources', $this->Job->Company->find('first', array( 'conditions' => array( 'Company.id' => $company_id ), 'contain' => array( 'Employee', 'Truck', 'Job' => array( 'conditions' => array( 'Job.assigned' => false, 'Job.pickup_date' => date('Y-m-d', strtotime('Today')); ) ) ) ))); Now, since writing this code, I decided to do a lot more with the job assignments. So I've created a new model "Assignment" that belongsTo Truck and belongsTo Job. I've added the hasMany Assignments to both the Truck model and the Jobs Model. I have both foreign keys in the assignments table, along with some other assignment fields. Now, I'm trying to get the same information above, only instead of checking the assigned field from the job table, I want to check the assignments table to ensure that the job does not exist there. I can no longer use the containable behavior if I'm going to use the "joins" feature of the find method due to mysql errors (according to the cookbook). But, the following query returns all jobs, even if they fall on different days. $this->set('resources', $this->Job->Company->find('first', array( 'joins' => array( array( 'table' => 'employees', 'alias' => 'Employee', 'type' => 'LEFT', 'conditions' => array( 'Company.id = Employee.company_id' ) ), array( 'table' => 'trucks', 'alias' => 'Truck', 'type' => 'LEFT', 'conditions' => array( 'Company.id = Truck.company_id' ) ), array( 'table' => 'jobs', 'alias' => 'Job', 'type' => 'LEFT', 'conditions' => array( 'Company.id = Job.company_id' ) ), array( 'table' => 'assignments', 'alias' => 'Assignment', 'type' => 'LEFT', 'conditions' => array( 'Job.id = Assignment.job_id' ) ) ), 'conditions' => array( 'Job.pickup_date' => $day, 'Company.id' => $company_id, 'Assignment.job_id IS NULL' ) )));

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• How does formatting works with a PowerShell function that returns a set of elements?

  - by Steve B

  If I write this small function : function Foo { Get-Process | % { $_ } } And if I run Foo It displays only a small subset of properties: PS C:\Users\Administrator> foo Handles NPM(K) PM(K) WS(K) VM(M) CPU(s) Id ProcessName ------- ------ ----- ----- ----- ------ -- ----------- 86 10 1680 412 31 0,02 5916 alg 136 10 2772 2356 78 0,06 3684 atieclxx 123 7 1780 1040 33 0,03 668 atiesrxx ... ... But even if only 8 columns are shown, there are plenty of other properties (as foo | gm is showing). What is causing this function to show only this 8 properties? I'm actually trying to build a similar function that is returning complex objects from a 3rd party .Net library. The library is flatting a 2 level hierarchy of objects : function Actual { $someDotnetObject.ACollectionProperty.ASecondLevelCollection | % { $_ } } This method is dumping the objects in a list form (one line per property). How can I control what is displayed, keeping the actual object available? I have tried this : function Actual { $someDotnetObject.ACollectionProperty.ASecondLevelCollection | % { $_ } | format-table Property1, Property2 } It shows in a console the expected table : Property1 Property2 --------- --------- ValA ValD ValB ValE ValC ValF But I lost my objects. Running Get-Member on the result shows : TypeName: Microsoft.PowerShell.Commands.Internal.Format.FormatStartData Name MemberType Definition ---- ---------- ---------- Equals Method bool Equals(System.Object obj) GetHashCode Method int GetHashCode() GetType Method type GetType() ToString Method string ToString() autosizeInfo Property Microsoft.PowerShell.Commands.Internal.Format.AutosizeInfo autosizeInfo {get;set;} ClassId2e4f51ef21dd47e99d3c952918aff9cd Property System.String ClassId2e4f51ef21dd47e99d3c952918aff9cd {get;} groupingEntry Property Microsoft.PowerShell.Commands.Internal.Format.GroupingEntry groupingEntry {get;set;} pageFooterEntry Property Microsoft.PowerShell.Commands.Internal.Format.PageFooterEntry pageFooterEntry {get;set;} pageHeaderEntry Property Microsoft.PowerShell.Commands.Internal.Format.PageHeaderEntry pageHeaderEntry {get;set;} shapeInfo Property Microsoft.PowerShell.Commands.Internal.Format.ShapeInfo shapeInfo {get;set;} TypeName: Microsoft.PowerShell.Commands.Internal.Format.GroupStartData Name MemberType Definition ---- ---------- ---------- Equals Method bool Equals(System.Object obj) GetHashCode Method int GetHashCode() GetType Method type GetType() ToString Method string ToString() ClassId2e4f51ef21dd47e99d3c952918aff9cd Property System.String ClassId2e4f51ef21dd47e99d3c952918aff9cd {get;} groupingEntry Property Microsoft.PowerShell.Commands.Internal.Format.GroupingEntry groupingEntry {get;set;} shapeInfo Property Microsoft.PowerShell.Commands.Internal.Format.ShapeInfo shapeInfo {get;set;} Instead of showing the 2nd level child object members. In this case, I can't pipe the result to functions waiting for this type of argument. How does Powershell is supposed to handle such scenario?

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• Mongoid Embeds_many won't save on nested form

  - by Brandon J McKay

  I've got an embeds_many association I'm trying to set up which I've done successfully before, but I'm trying to do it all in one nested form and I can't figure it out. Let's say we have a pocket model: class Pocket include Mongoid::Document field :title, type: String embeds_many :coins, cascade_callbacks: true end and a Coin Model: class Coin include Mongoid::Document field :name, type: String embedded_in :pocket end in my form for the pocket, I'm using: = f.fields_for @pocket.coins do |coin| = coin.text_field :name My controller is the default scaffolded controller. When I use the console, it saves fine and I can see the new pocket and coin I've created. But when I try to create or update a coin from the form, the pocket saves but the coin remains unchanged. What am I missing here?

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• Can we add shadow into WPF 3D

  - by terenf

  How to make a shadow for a 3D model in WPF?

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• Scaling Java applications - existing cluster-aware IoC frameworks?

  - by Zoltan

  Most people use some kind of an IoC framework - Guice, Spring, you name it. Many of us need to scale their applications too, so they complicate their lifes with Terracotta, Glassfish/JBoss/insertyourfavouritehere clusters. But is it really the way to go? Are you using any of the above? Here's some ideas we currently have implemented in a yet-to-be-opensourced framework, and I'd like to see what you think of it, or maybe "it's a complete ripoff of XY!". cluster-wide object replication - give it a name, and whenever you do something (in any node) on such an object, it will get replicated - with different guarantees do transparent soft-loadbalancing - simplest scenario: restful webservice method call proxied to an other node view-only node injection: inject a proxy to a "named" object, and get your calls automatically proxied to a node Would you use something like that? Is there a current, stable, enterprise-ready implementation out there?

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• General ORM design question

  - by Calvin

  Suppose you have 2 classes, Person and Rabbit. A person can do a number of things to a rabbit, s/he can either feed it, buy it and become its owner, or give it away. A rabbit can have none or at most 1 owner at a time. And if it is not fed for a while, it may die. Class Person { Void Feed(Rabbit r); Void Buy(Rabbit r); Void Giveaway(Person p, Rabbit r); Rabbit[] rabbits; } Class Rabbit { Bool IsAlive(); Person pwner; } There are a couple of observations from the domain model: Person and Rabbit can have references to each other Any actions on 1 object can also change the state of the other object Even if no explicit actions are invoked, there can still be a change of state in the objects (e.g. Rabbit can be starved to death, and that causes it to be removed from the Person.rabbits array) As DDD is concerned, I think the correct approach is to synchronize all calls that may change the states in the domain model. For instance, if a Person buys a Rabbit, s/he would need to acquire a lock in Person to make a change to the rabbits array AND also another lock in Rabbit to change its owner before releasing the first one. This would prevent a race condition where 2 Persons claim to be the owner of the little Rabbit. The other approach is to let the database to handle all these synchronizations. Who makes the first call wins, but then the DB needs to have some kind of business logics to figure out if it is a valid transaction (e.g. if a Rabbit already has an owner, it cannot change its owner unless the Person gives it away). There are both pros/cons in either approach, and I’d expect the “best” solution would be somewhere in-between. How would you do it in real life? What’s your take and experience? Also, is it a valid concern that there can be another race condition the domain model has committed its change but before it is fully committed in the database? And for the 3rd observation (i.e. state change due to time factor). How will you do it?

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