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  • How to parse (infinite) nested object notation?

    - by kyogron
    I am currently breaking my head about transforming this object hash: "food": { "healthy": { "fruits": ['apples', 'bananas', 'oranges'], "vegetables": ['salad', 'onions'] }, "unhealthy": { "fastFood": ['burgers', 'chicken', 'pizza'] } } to something like this: food:healthy:fruits:apples food:healthy:fruits:bananas food:healthy:fruits:oranges food:healthy:vegetables:salad food:healthy:vegetables:onions food:unhealthy:fastFood:burgers food:unhealthy:fastFood:chicken food:unhealthy:fastFood:pizza In theory it actually is just looping through the object while keeping track of the path and the end result. Unfortunately I do not know how I could loop down till I have done all nested. var path; var pointer; function loop(obj) { for (var propertyName in obj) { path = propertyName; pointer = obj[propertyName]; if (pointer typeof === 'object') { loop(pointer); } else { break; } } }; function parse(object) { var collection = []; }; There are two issues which play each out: If I use recurse programming it looses the state of the properties which are already parsed. If I do not use it I cannot parse infinite. Is there some idea how to handle this? Regards

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  • JPA: persisting object, parent is ok but child not updated

    - by James.Elsey
    Hello, I have my domain object, Client, I've got a form on my JSP that is pre-populated with its data, I can take in amended values, and persist the object. Client has an abstract entity called MarketResearch, which is then extended by one of three more concrete sub-classes. I have a form to pre-populate some MarketResearch data, but when I make changes and try to persist the Client, it doesn't get saved, can someone give me some pointers on where I've gone wrong? My 3 domain classes are as follows (removed accessors etc) public class Client extends NamedEntity { @OneToOne @JoinColumn(name = "MARKET_RESEARCH_ID") private MarketResearch marketResearch; ... } @Inheritance(strategy = InheritanceType.JOINED) public abstract class MarketResearch extends AbstractEntity { ... } @Entity(name="MARKETRESEARCHLG") public class MarketResearchLocalGovernment extends MarketResearch { @Column(name = "CURRENT_HR_SYSTEM") private String currentHRSystem; ... } This is how I'm persisting public void persistClient(Client client) { if (client.getId() != null) { getJpaTemplate().merge(client); getJpaTemplate().flush(); } else { getJpaTemplate().persist(client); } } To summarize, if I change something on the parent object, it persists, but if I change something on the child object it doesn't. Have I missed something blatantly obvious? Thanks

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  • Trying to import SQL file in a xampp server returns error

    - by Victor_J_Martin
    I have done a ER diagram in Mysql Workbench, and I am trying load in my server with phpMyAdmin, but it returns me the next error: Error SQL Query: -- ----------------------------------------------------- -- Table `BDA`.`UG` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`UG` ( `numero_ug` INT NOT NULL, `nombre` VARCHAR(45) NOT NULL, `segunda_firma_autorizada` VARCHAR(45) NOT NULL, `fecha_creacion` DATE NOT NULL, `nombre_depto` VARCHAR(140) NOT NULL, `dni` INT NOT NULL, `anho_contable` INT NOT NULL, PRIMARY KEY (`numero_ug`), INDEX `nombre_depto_idx` (`nombre_depto` ASC), INDEX `dni_idx` (`dni` ASC), INDEX `anho_contable_idx` (`anho_contable` ASC), CONSTRAINT `nombre_depto` FOREIGN KEY (`nombre_depto`) REFERENCES `BDA`.`Departamento` (`nombre_depto`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `dni` FOREIGN KEY (`dni`) REFERENCES `BDA`.`Trabajador` (`dni`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `anho_contable` FOREIGN KEY (`anho_contable`) REFERENCES `BDA`.`Capitulo_Contable` (`anho_contable`) [...] MySQL said: Documentation #1022 - Can't write; duplicate key in table 'ug' I export the result of the diagram from Mysql Workbench to a SQL file, and this file is what I'm trying to upload. This is the file. I can not find the duplicate key. SET @OLD_UNIQUE_CHECKS=@@UNIQUE_CHECKS, UNIQUE_CHECKS=0; SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0; SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='TRADITIONAL,ALLOW_INVALID_DATES'; CREATE SCHEMA IF NOT EXISTS `BDA` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci ; USE `BDA` ; -- ----------------------------------------------------- -- Table `BDA`.`Departamento` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Departamento` ( `nombre_depto` VARCHAR(140) NOT NULL, `area_depto` VARCHAR(140) NOT NULL, PRIMARY KEY (`nombre_depto`)) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Trabajador` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Trabajador` ( `dni` INT NOT NULL, `direccion` VARCHAR(140) NOT NULL, `nombre` VARCHAR(45) NOT NULL, `apellidos` VARCHAR(140) NOT NULL, `fecha_nacimiento` DATE NOT NULL, `fecha_contrato` DATE NOT NULL, `titulacion` VARCHAR(140) NULL, `nombre_depto` VARCHAR(45) NOT NULL, PRIMARY KEY (`dni`), INDEX `nombre_depto_idx` (`nombre_depto` ASC), CONSTRAINT `nombre_depto` FOREIGN KEY (`nombre_depto`) REFERENCES `BDA`.`Departamento` (`nombre_depto`) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Capitulo_Contable` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Capitulo_Contable` ( `anho_contable` INT NOT NULL, `numero_ug` INT NOT NULL, `debe` DOUBLE NOT NULL, `haber` DOUBLE NOT NULL, PRIMARY KEY (`anho_contable`), INDEX `numero_ug_idx` (`numero_ug` ASC), CONSTRAINT `numero_ug` FOREIGN KEY (`numero_ug`) REFERENCES `BDA`.`UG` (`numero_ug`) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`UG` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`UG` ( `numero_ug` INT NOT NULL, `nombre` VARCHAR(45) NOT NULL, `segunda_firma_autorizada` VARCHAR(45) NOT NULL, `fecha_creacion` DATE NOT NULL, `nombre_depto` VARCHAR(140) NOT NULL, `dni` INT NOT NULL, `anho_contable` INT NOT NULL, PRIMARY KEY (`numero_ug`), INDEX `nombre_depto_idx` (`nombre_depto` ASC), INDEX `dni_idx` (`dni` ASC), INDEX `anho_contable_idx` (`anho_contable` ASC), CONSTRAINT `nombre_depto` FOREIGN KEY (`nombre_depto`) REFERENCES `BDA`.`Departamento` (`nombre_depto`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `dni` FOREIGN KEY (`dni`) REFERENCES `BDA`.`Trabajador` (`dni`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `anho_contable` FOREIGN KEY (`anho_contable`) REFERENCES `BDA`.`Capitulo_Contable` (`anho_contable`) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Cliente` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Cliente` ( `cif_cliente` INT NOT NULL, `nombre_cliente` VARCHAR(140) NOT NULL, PRIMARY KEY (`cif_cliente`)) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Ingreso` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Ingreso` ( `id` INT NOT NULL, `concepto` VARCHAR(45) NOT NULL, `importe` DOUBLE NOT NULL, `fecha` DATE NOT NULL, `cif_cliente` INT NOT NULL, `numero_ug` INT NOT NULL, PRIMARY KEY (`id`), INDEX `cif_cliente_idx` (`cif_cliente` ASC), INDEX `numero_ug_idx` (`numero_ug` ASC), CONSTRAINT `cif_cliente` FOREIGN KEY (`cif_cliente`) REFERENCES `BDA`.`Cliente` (`cif_cliente`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `numero_ug` FOREIGN KEY (`numero_ug`) REFERENCES `BDA`.`UG` (`numero_ug`) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Proveedor` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Proveedor` ( `cif_proveedor` INT NOT NULL, `nombre_proveedor` VARCHAR(140) NOT NULL, PRIMARY KEY (`cif_proveedor`)) ENGINE = InnoDB; -- ----------------------------------------------------- -- Table `BDA`.`Gasto` -- ----------------------------------------------------- CREATE TABLE IF NOT EXISTS `BDA`.`Gasto` ( `id` INT NOT NULL, `concepto` VARCHAR(45) NOT NULL, `importe` DOUBLE NOT NULL, `fecha` DATE NOT NULL, `factura` INT NOT NULL, `cif_proveedor` INT NOT NULL, `numero_ug` INT NOT NULL, PRIMARY KEY (`id`), INDEX `cif_proveedor_idx` (`cif_proveedor` ASC), INDEX `numero_ug_idx` (`numero_ug` ASC), CONSTRAINT `cif_proveedor` FOREIGN KEY (`cif_proveedor`) REFERENCES `BDA`.`Proveedor` (`cif_proveedor`) ON DELETE NO ACTION ON UPDATE NO ACTION, CONSTRAINT `numero_ug` FOREIGN KEY (`numero_ug`) REFERENCES `BDA`.`UG` (`numero_ug`) ON DELETE NO ACTION ON UPDATE NO ACTION) ENGINE = InnoDB; SET SQL_MODE=@OLD_SQL_MODE; SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS; SET UNIQUE_CHECKS=@OLD_UNIQUE_CHECKS; Thanks for your advices.

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  • Reverse-engineer a Javascript object?

    - by TruMan1
    I have a Javascript object that I want to pass in more parameters, but the documentation is non-existant. My only option seems to be to reverse engineer the Javascript object to see what parameters and values I can pass in. For example, I want to see if there is a "zoom" parameter for the object and what values I can pass into the "mapType" parameter: <script type="text/javascript" src="http://maps.google.com/maps?oe=utf-8&amp;file=api&amp;v=2&amp;key=your-gmap-key"></script> <script type="text/javascript" src="https://share.findmespot.com/spot-widget/js/SpotMain.js"></script> <script type="text/javascript"> var widget = new Spot.Ui.LiveWidget({ renderTo: "spot-live-widget", feeds: [ "0Wl3diTJcqqvncI6NNsoqJV5ygrFtQfBB" ], height: 400, width: 500, mapType: "physical" }); </script> <div id="spot-live-widget"/> Any ideas on how to do that?

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  • How to implement List, Set, and Map in null free design?

    - by Pyrolistical
    Its great when you can return a null/empty object in most cases to avoid nulls, but what about Collection like objects? In Java, Map returns null if key in get(key) is not found in the map. The best way I can think of to avoid nulls in this situation is to return an Entry<T> object, which is either the EmptyEntry<T>, or contains the value T. Sure we avoid the null, but now you can have a class cast exception if you don't check if its an EmptyEntry<T>. Is there a better way to avoid nulls in Map's get(K)? And for argument sake, let's say this language don't even have null, so don't say just use nulls.

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  • In ParallelPython, a method of an object ( object.func() ) fails to manipulate a variable of an object ( object.value )

    - by mehmet.ali.anil
    With parallelpython, I am trying to convert my old serial code to parallel, which heavily relies on objects that have methods that change that object's variables. A stripped example in which I omit the syntax in favor of simplicity: class Network: self.adjacency_matrix = [ ... ] self.state = [ ... ] self.equilibria = [ ... ] ... def populate_equilibria(self): # this function takes every possible value that self.state can be in # runs the boolean dynamical system # and writes an integer within self.equilibria for each self.state # doesn't return anything I call this method as: Code: j1 = jobserver.submit(net2.populate_equilibria,(),(),("numpy as num")) The job is sumbitted, and I know that a long computation takes place, so I speculate that my code is ran. The problem is, i am new to parallelpython , I was expecting that, when the method is called, the variable net2.equilibria would be written accordingly, and I would get a revised object (net2) . That is how my code works, independent objects with methods that act upon the object's variables. Rather, though the computation is apparent, and reasonably timed, the variable net2.equilibria remains unchanged. As if PP only takes the function and the object, computes it elsewhere, but never returns the object, so I am left with the old one. What do I miss? Thanks in advance.

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  • NullPointerException in javax.swing.text.SimpleAttributeSet.addAttribute

    - by Paul Reiners
    Has anyone ever seen an exception like this?: ERROR: java.lang.NullPointerException: null at java.util.Hashtable.put(null:-1) at javax.swing.text.SimpleAttributeSet.addAttribute(null:-1) at javax.swing.text.SimpleAttributeSet.addAttributes(null:-1) at javax.swing.text.StyledEditorKit.createInputAttributes(null:-1) at javax.swing.text.StyledEditorKit$AttributeTracker.updateInputAttributes(null:-1) at javax.swing.text.StyledEditorKit$AttributeTracker.caretUpdate(null:-1) at javax.swing.text.JTextComponent.fireCaretUpdate(null:-1) at javax.swing.text.JTextComponent$MutableCaretEvent.fire(null:-1) at javax.swing.text.JTextComponent$MutableCaretEvent.mouseReleased(null:-1) at java.awt.AWTEventMulticaster.mouseReleased(null:-1) at java.awt.AWTEventMulticaster.mouseReleased(null:-1) at java.awt.Component.processMouseEvent(null:-1) at javax.swing.JComponent.processMouseEvent(null:-1) at java.awt.Component.processEvent(null:-1) at java.awt.Container.processEvent(null:-1) at java.awt.Component.dispatchEventImpl(null:-1) at java.awt.Container.dispatchEventImpl(null:-1) at java.awt.Component.dispatchEvent(null:-1) at java.awt.LightweightDispatcher.retargetMouseEvent(null:-1) at java.awt.LightweightDispatcher.processMouseEvent(null:-1) at java.awt.LightweightDispatcher.dispatchEvent(null:-1) at java.awt.Container.dispatchEventImpl(null:-1) at java.awt.Window.dispatchEventImpl(null:-1) at java.awt.Component.dispatchEvent(null:-1) at java.awt.EventQueue.dispatchEvent(null:-1) at java.awt.EventDispatchThread.pumpOneEventForFilters(null:-1) at java.awt.EventDispatchThread.pumpEventsForFilter(null:-1) at java.awt.EventDispatchThread.pumpEventsForHierarchy(null:-1) at java.awt.EventDispatchThread.pumpEvents(null:-1) at java.awt.EventDispatchThread.pumpEvents(null:-1) at java.awt.EventDispatchThread.run(null:-1) I wish I could tell you an easy way to reproduce this, but I can’t. It’s happening in a Java Swing application I maintain. It happens infrequently and the application is quite complex. I know it’s a bit of a long shot just showing this stack trace, but I thought I’d try.

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  • How Can I Check an Object to See its Type and Return A Casted Object

    - by Russ Bradberry
    I have method to which I pass an object. In this method I check it's type and depending on the type I do something with it and return a Long. I have tried every which way I can think of to do this and I always get several compiler errors telling me it expects a certain object but gets another. Can someone please explain to me what I am doing wrong and guide me in the right direction? What I have tried thus far is below: override def getInteger(obj:Object) = { if (obj.isInstanceOf[Object]) null else if (obj.isInstanceOf[Number]) (obj:Number).longValue() else if (obj.isInstanceOf[Boolean]) if (obj:Boolean) 1 else 0 else if (obj.isInstanceOf[String]) if ((obj:String).length == 0 | (obj:String) == "null") null else try { Long.parse(obj:String) } catch { case e: Exception => throw new ValueConverterException("value \"" + obj.toString() + "\" of type " + obj.getClass().getName() + " is not convertible to Long") } }

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  • How to include a child object's child object in Entity Framework 5

    - by Brendan Vogt
    I am using Entity Framework 5 code first and ASP.NET MVC 3. I am struggling to get a child object's child object to populate. Below are my classes.. Application class; public class Application { // Partial list of properties public virtual ICollection<Child> Children { get; set; } } Child class: public class Child { // Partial list of properties public int ChildRelationshipTypeId { get; set; } public virtual ChildRelationshipType ChildRelationshipType { get; set; } } ChildRelationshipType class: public class ChildRelationshipType { public int Id { get; set; } public string Name { get; set; } } Part of GetAll method in the repository to return all the applications: return DatabaseContext.Applications .Include("Children"); The Child class contains a reference to the ChildRelationshipType class. To work with an application's children I would have something like this: foreach (Child child in application.Children) { string childName = child.ChildRelationshipType.Name; } I get an error here that the object context is already closed. How do I specify that each child object must include the ChildRelationshipType object like what I did above?

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  • Object reference error even when object is not null

    - by Shrewd Demon
    hi, i have an application wherein i have incorporate a "Remember Me" feature for the login screen. I do this by creating a cookie when the user logs in for the first time, so next time when the user visits the site i get the cookie and load the user information. i have written the code for loading user information in a common class in the App_Code folder...and all my pages inherit from this class. code for loading the user info is as follows: public static void LoadUserDetails(string emailId) { UsersEnt currentUser = UsersBL.LoadUserInfo(emailId); if (currentUser != null) HttpContext.Current.Session["CurrentUser"] = currentUser; } Now the problem is i get an "Object reference" error when i try to store the currentUser object in the session variable (even though the currentUser object is not null). However the password property in the currentUser object is null. Am i getting the error because of this...or is there some other reason?? thank you

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  • search through related field for specific related object

    - by dotty
    Hay, I'm working on a simple voting system, where users can vote on a poll. My model looks like this class Poll(models.Model): question = models.CharField() votes = models.IntegerField() usersVoted = models.ManyToManyField(User) Now, i want to scan through the usersVoted field to see if a User object is in there. This User object will then be matched against a logged in User (User obj saved in a session). If the User has voted i want to be able to set a 'has_voted' field. I then want to use this field in my view. I will be using the Property() thingy inside the model to work this 'has_voted' value out. Like so def _can_vote(self): return False can_vote = property(_can_vote) Obviously it'll return a Bool. Any ideas how to search through a related field to find a specific Object?

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  • Null Safe dereferencing in Java like ?. in Groovy using Maybe monad

    - by Sathish
    I'm working on a codebase ported from Objective C to Java. There are several usages of method chaining without nullchecks dog.collar().tag().name() I was looking for something similar to safe-dereferencing operator ?. in Groovy instead of having nullchecks dog.collar?.tag?.name This led to Maybe monad to have the notion of Nothing instead of Null. But all the implementations of Nothing i came across throw exception when value is accessed which still doesn't solve the chaining problem. I made Nothing return a mock, which behaves like NullObject pattern. But it solves the chaining problem. Is there anything wrong with this implementation of Nothing? [http://github.com/sathish316/jsafederef/blob/master/src/s2k/util/safederef/Nothing.java] As far as i can see 1. It feels odd to use mocking library in code 2. It doesn't stop at the first null. 3. How do i distinguish between null result because of null reference or name actually being null? How is it distinguished in Groovy code?

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  • How to reference a specific object in an array of objects using jTemplates

    - by Travis
    I am using the excellent jTemplates plugin to generate content. Given a data object like this... var data = { name: 'datatable', table: [ {id: 1, name: 'Anne'}, {id: 2, name: 'Amelie'}, {id: 3, name: 'Polly'}, {id: 4, name: 'Alice'}, {id: 5, name: 'Martha'} ] }; ..I'm wondering if it is possible to directly specify an object in an array of objects using $T. (I'm hoping there is something like $T.table:3 available) Currently the only way I can think of to access a specific object in an array is to do something like this... {#foreach $T.table as record} {#if $T.record$iteration == 3} This is record 3! Name: {$T.record.name} {#/if} {#/for} However that seems clumsy... Any suggestions? Thanks

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  • Create an object in C# from an F# object with optional arguments

    - by Mark Pearl
    I have a object in F# as follows... type Person(?name : string) = let name = defaultArg name "" member x.Name = name I want to be able to create an instance of this object in a C# project. I have added as a reference the correct libraries to the project and can see the object via intellisense however I am not sure on the correct syntaxt to create an instance of the object. Currently I have the following in my C# project - which the compiler doesn't like... var myObj1 = new Person("mark");

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  • Passing null as a param for replace() in javascript behaving weird?

    - by Babiker
    I have the follwing jQuery: $("#textArea").keyup(function(){ var textAreaValue = $("textArea"); if(!textArea.value.indexOf("some string")){ textArea.value = textArea.value.replace("some string",null); alert("It was there!"); } }); Is it normal for element.value.replace("some string",null); to replace "some string" with "null"as a string? And if normal can you please explain why? I have tested it with element.value.replace("some string",""), and that works fine, so what would be the difference between null and ""? Thanks in advance.

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  • firefox object height ignored when data

    - by John Rygielski
    I have a flash video loading in a modal window. It works in others browsers but not Firefox. Firefox opens the modal window to the correct width of the object, but with no height. I have come to learn that Firefox does not recognize <param> and instead uses the data attribute. However, when I remove this attribute, the modal opens with correct height. What is going on? Here is the code the modal window loads: <object width="720" height="520" type="application/x-shockwave-flash" data="proxymovie.SWF?file=proxymovie.MP4"> <param name="movie" value="proxymovie.SWF?file=proxymovie.MP4" /> <img src="images/poster.png" width="720" height="480" alt="" title="Download the video below" /> </object>

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  • Linux friendly (.NET/Mono) browser object?

    - by HankB
    Hi folks, A friend of mine (familiar with C# and .NET on Windows) has asked how to port some functionality to a Linux host. This functionality is based on a JSP web page that fetches some data from the host server and displays it in a banner on a page. His Win/C#/.NET code simply creates a browser object which loads the page and he then inspects the resulting object to extract the data. I'm wondering what alternatives exist to duplicate this function on Ubuntu Linux. I'm not certain that the necessary libraries exist on this installation. I can assume that things like Perl and Python are ubiquitous, but I am not familiar with any libraries that include a browser object capable of executing javascript and exposing the results to another program. Any suggestions that lead in this direction are welcome. Thanks!

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  • bool as object vs string as object testing equality

    - by Ray Pendergraph
    I am relatively new to C# and I noticed something interesting today that I guess I have never noticed or perhaps I am missing something. Here is an NUnit test to give an example: object boolean1 = false; object booloan2 = false; Assert.That(boolean1 == booloan2); This unit test fails, but this one passes: object string1 = "string"; object string2 = "string"; Assert.That(string1 == string2); I'm not that surprised in and of itself that the first one fails seeing as boolean1 and boolean2 are different references. But it is troubling to me that the first one fails and the second one passes. I read (on MSDN somewhere) that some magic was done to the String class to facilitate this. I think my question really is why wasn't this behavior replicated in bool? As a note... if the boolean1 and 2 are declared as "bool" then there is no problem. Does anyone know the reason for these differences or why it was implemented that way? Can anyone think of a situation where you would want to reference a bool object for anything except its value?

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  • Vector of Object Pointers, general help and confusion

    - by Staypuft
    Have a homework assignment in which I'm supposed to create a vector of pointers to objects Later on down the load, I'll be using inheritance/polymorphism to extend the class to include fees for two-day delivery, next day air, etc. However, that is not my concern right now. The final goal of the current program is to just print out every object's content in the vector (name & address) and find it's shipping cost (weight*cost). My Trouble is not with the logic, I'm just confused on few points related to objects/pointers/vectors in general. But first my code. I basically cut out everything that does not mater right now, int main, will have user input, but right now I hard-coded two examples. #include <iostream> #include <string> #include <vector> using namespace std; class Package { public: Package(); //default constructor Package(string d_name, string d_add, string d_zip, string d_city, string d_state, double c, double w); double calculateCost(double, double); void Print(); ~Package(); private: string dest_name; string dest_address; string dest_zip; string dest_city; string dest_state; double weight; double cost; }; Package::Package() { cout<<"Constucting Package Object with default values: "<<endl; string dest_name=""; string dest_address=""; string dest_zip=""; string dest_city=""; string dest_state=""; double weight=0; double cost=0; } Package::Package(string d_name, string d_add, string d_zip, string d_city, string d_state, string r_name, string r_add, string r_zip, string r_city, string r_state, double w, double c){ cout<<"Constucting Package Object with user defined values: "<<endl; string dest_name=d_name; string dest_address=d_add; string dest_zip=d_zip; string dest_city=d_city; string dest_state=d_state; double weight=w; double cost=c; } Package::~Package() { cout<<"Deconstructing Package Object!"<<endl; delete Package; } double Package::calculateCost(double x, double y){ return x+y; } int main(){ double cost=0; vector<Package*> shipment; cout<<"Enter Shipping Cost: "<<endl; cin>>cost; shipment.push_back(new Package("tom r","123 thunder road", "90210", "Red Bank", "NJ", cost, 10.5)); shipment.push_back(new Package ("Harry Potter","10 Madison Avenue", "55555", "New York", "NY", cost, 32.3)); return 0; } So my questions are: I'm told I have to use a vector of Object Pointers, not Objects. Why? My assignment calls for it specifically, but I'm also told it won't work otherwise. Where should I be creating this vector? Should it be part of my Package Class? How do I go about adding objects into it then? Do I need a copy constructor? Why? What's the proper way to deconstruct my vector of object pointers? Any help would be appreciated. I've searched for a lot of related articles on here and I realize that my program will have memory leaks. Using one of the specialized ptrs from boost:: will not be available for me to use. Right now, I'm more concerned with getting the foundation of my program built. That way I can actually get down to the functionality I need to create. Thanks.

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  • Metric to measure object-orientedness

    - by Jono
    Is there a metric that can assist in determining the object-orientedness of a system or application? I've seen some pretty neat metrics in the .NET Reflector Add-ins codeplex project, but nothing like this yet. If such a metric doesn't exist, would it even be possible or useful? There are the 3 supposed tenets of object-oriented programming: encapsulation, inheritance, and polymorphism; a tool that ranked programs against these might be able to show areas of a C# (or similar) code base where the whole object-oriented ideal was discarded, and perhaps how many bugs are associated with that area versus the rest of the project.

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  • Creating a Mysql view to SELECT coloumns from different tables

    - by user330429
    I need help in constructing a VIEW on 4 tables. The view should contain coloumns: ER.ID, ER.EMPID, ER.CUSTID, ER.STATUS, ER.DATEREPORTED, ER.REPORT, EB.NAME, CR.CUSTNAME, CR.LOCID, CL.LOCNAME, DI.DEPTNAME ALIASES EMP_REPORT ER , EMP_BIO EB, CUST_RECORD CR, CUST_LOC CL, DEPT_ID DI THE DATA MODELS ARE: describe EMP_REPORT; +--------------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +--------------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | empid | int(11) | NO | | NULL | | | custid | int(11) | NO | | NULL | | | status | varchar(32) | NO | | NULL | | | datereported | bigint(20) | NO | | NULL | | | report | text | YES | | NULL | | +--------------+-------------+------+-----+---------+----------------+ describe EMP_BIO; +--------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +--------+-------------+------+-----+---------+-------+ | empid | int(11) | NO | PRI | NULL | | | name | varchar(56) | NO | | NULL | | | sex | char(1) | NO | | NULL | | | deptid | int(11) | NO | | NULL | | | email | varchar(32) | NO | | NULL | | | mobile | bigint(20) | YES | | NULL | | | gtlk | varchar(32) | YES | | NULL | | | skype | varchar(32) | YES | | NULL | | | cvid | int(11) | YES | | NULL | | +--------+-------------+------+-----+---------+-------+ describe CUST_RECORD; +----------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +----------+--------------+------+-----+---------+----------------+ | custid | int(11) | NO | PRI | NULL | auto_increment | | custname | varchar(32) | NO | | NULL | | | address | varchar(255) | YES | | NULL | | | contactp | varchar(32) | YES | | NULL | | | mobile | bigint(20) | YES | | NULL | | | locid | int(11) | NO | | NULL | | | remarks | text | YES | | NULL | | | date | int(11) | YES | | NULL | | | addedby | int(11) | YES | | NULL | | +----------+--------------+------+-----+---------+----------------+ describe CUST_LOC; +---------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +---------+-------------+------+-----+---------+-------+ | locid | int(11) | NO | PRI | 0 | | | locname | varchar(32) | NO | | NULL | | +---------+-------------+------+-----+---------+-------+ describe DEPT_ID; +----------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +----------+-------------+------+-----+---------+-------+ | deptid | int(11) | NO | | NULL | | | deptname | varchar(32) | YES | | NULL | | +----------+-------------+------+-----+---------+-------+ The table EMP_REPORT contains reports submitted by employees, all the coloumns in it needs to be fetched. The empid in this table should be used to fetch corresponding name in EMP_BIO (employee biodata) table. The custid in EMP_REPORT should be used to fetch corresponding locid in CUST_RECORD(customer record) which is used to fetch locname in CUST_LOC(customer location) table. The empid in EMP_REPORT is used to fetch corresponding deptid in EMP_BIO table which is then used to fetch corresponding deptname from DEPT_ID(department id) table. I tried constructing view using union of different select queries, but dint get proper results. Please help me. Thanks in advance. PS: sorry for my poor english

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  • Parent-Child relation while using object data source

    - by Saba
    Hello guys I am experiencing with a class generator I've written, which generates a class for each table in database with each table field as a property and such. Before that, I used to add a typed dataset to the project and add some tables to it. It automatically detected the relationship between tables and when I added a parent table as data source of a datagrid, I could add another datagrid and use the foreing key data member of it's bindingsource to fill it, and when someone moved the focus on parent datagrid, the data in child datagrid would change accordingly. Now that I have my classes, I add an object as data source for my 2 datagrids, but obviously it doesn't detect a parent child relation. But It'd really help if I could have that foreign key relation in my object datasources. Is there any way to have that relation in object datasource?

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