Search Results

Search found 47799 results on 1912 pages for 'class attributes'.

Page 652/1912 | < Previous Page | 648 649 650 651 652 653 654 655 656 657 658 659  | Next Page >

  • Django query get recent record for each entry and display as combined list

    - by gtujan
    I have two models device and log setup as such: class device(models.Model): name = models.CharField(max_length=20) code = models.CharField(max_length=10) description = models.TextField() class log(model.Model): device = models.ForeignKey(device) date = models.DateField() time = models.TimeField() data = models.CharField(max_length=50) how do I get a list which contains only the most recent record/log (based on time and date) for each device and combine them in the format below: name,code,date,time,data being a Django newbie I would like to implement this using Django's ORM. TIA!

    Read the article

  • In Ruby, how does coerce() actually work?

    - by Jian Lin
    It is said that when we have a class Point and knows how to perform point * 3 like the following: class Point def initialize(x,y) @x, @y = x, y end def *(c) Point.new(@x * c, @y * c) end end point = Point.new(1,2) p point p point * 3 Output: #<Point:0x336094 @x=1, @y=2> #<Point:0x335fa4 @x=3, @y=6> but then, 3 * point is not understood: Point can't be coerced into Fixnum (TypeError) So we need to further define an instance method coerce: class Point def coerce(something) [self, something] end end p 3 * point Output: #<Point:0x3c45a88 @x=3, @y=6> So it is said that 3 * point is the same as 3.*(point) that is, the instance method * takes an argument point and invoke on the object 3. Now, since this method * doesn't know how to multiply a point, so point.coerce(3) will be called, and get back an array: [point, 3] and then * is once again applied to it, is that true? point * 3 which is the same as point.*(3) and now, this is understood and we now have a new Point object, as performed by the instance method * of the Point class. The question is: 1) who invokes point.coerce(3) ? Is it Ruby automatically, or is it some code inside of * method of Fixnum by catching an exception? Or is it by case statement that when it doesn't know one of the known types, then call coerce? 2) Does coerce always need to return an array of 2 elements? Can it be no array? Or can it be an array of 3 elements? 3) And is the rule that, the original operator (or method) * will then be invoked on element 0, with the argument of element 1? (element 0 and element 1 are the two elements in that array returned by coerce) Who does it? Is it done by Ruby or is it done by code in Fixnum? If it is done by code in Fixnum, then it is a "convention" that everybody follows when doing a coerce? So could it be the code in * of Fixnum do something like this: if (something.typeof? ...) else if ... # other type else if ... # other type else # if it is not a type I know array = something.coerce(self) return array[0].*(array[1]) end

    Read the article

  • Object slicing in Java.

    - by ferrari fan
    Can you take a subclass object and somehow convert it to an object of the same type as the parent class and at the same time slicing all the fields that are not part of the parent class? I know you can do this in C++, but I have no idea how to do it in Java.

    Read the article

  • Different behaviour using unidirectional or bidirectional relation

    - by sinuhepop
    I want to persist a mail entity which has some resources (inline or attachment). First I related them as a bidirectional relation: @Entity public class Mail extends BaseEntity { @OneToMany(mappedBy = "mail", cascade = CascadeType.ALL, orphanRemoval = true) private List<MailResource> resource; private String receiver; private String subject; private String body; @Temporal(TemporalType.TIMESTAMP) private Date queued; @Temporal(TemporalType.TIMESTAMP) private Date sent; public Mail(String receiver, String subject, String body) { this.receiver = receiver; this.subject = subject; this.body = body; this.queued = new Date(); this.resource = new ArrayList<>(); } public void addResource(String name, MailResourceType type, byte[] content) { resource.add(new MailResource(this, name, type, content)); } } @Entity public class MailResource extends BaseEntity { @ManyToOne(optional = false) private Mail mail; private String name; private MailResourceType type; private byte[] content; } And when I saved them: Mail mail = new Mail("[email protected]", "Hi!", "..."); mail.addResource("image", MailResourceType.INLINE, someBytes); mail.addResource("documentation.pdf", MailResourceType.ATTACHMENT, someOtherBytes); mailRepository.save(mail); Three inserts were executed: INSERT INTO MAIL (ID, BODY, QUEUED, RECEIVER, SENT, SUBJECT) VALUES (?, ?, ?, ?, ?, ?) INSERT INTO MAILRESOURCE (ID, CONTENT, NAME, TYPE, MAIL_ID) VALUES (?, ?, ?, ?, ?) INSERT INTO MAILRESOURCE (ID, CONTENT, NAME, TYPE, MAIL_ID) VALUES (?, ?, ?, ?, ?) Then I thought it would be better using only a OneToMany relation. No need to save which Mail is in every MailResource: @Entity public class Mail extends BaseEntity { @OneToMany(cascade = CascadeType.ALL, orphanRemoval = true) @JoinColumn(name = "mail_id") private List<MailResource> resource; ... public void addResource(String name, MailResourceType type, byte[] content) { resource.add(new MailResource(name, type, content)); } } @Entity public class MailResource extends BaseEntity { private String name; private MailResourceType type; private byte[] content; } Generated tables are exactly the same (MailResource has a FK to Mail). The problem is the executed SQL: INSERT INTO MAIL (ID, BODY, QUEUED, RECEIVER, SENT, SUBJECT) VALUES (?, ?, ?, ?, ?, ?) INSERT INTO MAILRESOURCE (ID, CONTENT, NAME, TYPE) VALUES (?, ?, ?, ?) INSERT INTO MAILRESOURCE (ID, CONTENT, NAME, TYPE) VALUES (?, ?, ?, ?) UPDATE MAILRESOURCE SET mail_id = ? WHERE (ID = ?) UPDATE MAILRESOURCE SET mail_id = ? WHERE (ID = ?) Why this two updates? I'm using EclipseLink, will this behaviour be the same using another JPA provider as Hibernate? Which solution is better?

    Read the article

  • Generating JSON request manually, returned HTML causing issues.

    - by mrblah
    Hi, I am generating my JSON manually, and I even escaped for quotes with a preceding backslash. It is causing me problems. My HTML returned looks something like: <div class="blah"><div class="a2">This is just a test! I hope this work's man!</div></div> string json = "MY HTML HERE"; json = json.Replace(@"""", @"\"""); Is there more to replace than just the double quotes?

    Read the article

  • Deriving from a component and implementing IDisposable properly

    - by PaulH
    I have a Visual Studio 2008 C# .NET 2.0 CF project with an abstract class derived from Component. From that class, I derive several concrete classes (as in my example below). But, when I go to exit my Form, though the Form's Dispose() member is called and components.Dispose() is called, my components are never disposed. Can anybody suggest how I can fix this design? public abstract class SomeDisposableComponentBase : Component { private System.ComponentModel.IContainer components; protected SomeDisposableComponentBase() { Initializecomponent(); } protected SomeDisposableComponentBase(IContainer container) { container.Add(this); Initializecomponent(); } private void InitializeComponent() { components = new System.ComponentModel.Container(); } protected abstract void Foo(); #region IDisposable Members bool disposed_; /// Warning 60 CA1063 : Microsoft.Design : Ensure that 'SomeDisposableComponentBase.Dispose()' is declared as public and sealed.* public void Dispose() { // never called Dispose(true); GC.SuppressFinalize(this); } protected virtual void Dispose(bool disposing) { // never called if (!disposed_) { if (disposing && (components != null)) { components.Dispose(); } disposed_ = true; } base.Dispose(disposing); } #endregion } public SomeDisposableComponent : SomeDisposableComponentBase { public SomeDisposableComponent() : base() { } public SomeDisposableComponent(IContainer container) : base(container) { } protected override void Foo() { // Do something... } protected override void Dispose(bool disposing) { // never called base.Dispose(disposing); } } public partial class my_form : Form { private SomeDisposableComponentBase d_; public my_form() { InitializeComponent(); if (null == components) components = new System.ComponentModel.Container(); d_ = new SomeDisposableComponent(components); } /// exit button clicked private void Exit_Click(object sender, EventArgs e) { this.Close(); } /// from the my_form.designer.cs protected override void Dispose(bool disposing) { if (disposing && (components != null)) { // this function is executed as expected when the form is closed components.Dispose(); } base.Dispose(disposing); } } *I note that FX-Cop is giving me a hint here. But, if I try to declare that function as sealed, I get the error: error CS0238: 'SomeDisposableComponentBase.Dispose()' cannot be sealed because it is not an override Declaring that function an override leads to: 'SomeDisposableComponentBase.Dispose()': cannot override inherited member 'System.ComponentModel.Component.Dispose()' because it is not marked virtual, abstract, or override Thanks, PaulH

    Read the article

  • Is there some performance issue between leaving empty ListProperties or using dynamic (expando) prop

    - by indiehacker
    Is there a datastore performance difference between adding dynamic properties of the expando class when they are needed for an entity or the simpler (for me) framework of just setting up all possible properties I might need from the start even though most instances will just be left empty. In my specific case I would be having 5-8 empty ReferenceList properties as 'overhead' that will be empty when I skip using expando class.

    Read the article

  • Why is javac 1.5 running so slowly compared with the Eclipse compiler?

    - by Simon Nickerson
    I have a Java Maven project with about 800 source files (some generated by javacc/JTB) which is taking a good 25 minutes to compile with javac. When I changed my pom.xml over to use the Eclipse compiler, it takes about 30 seconds to compile. Any suggestions as to why javac (1.5) is running so slowly? (I don't want to switch over to the Eclipse compiler permanently, as the plugin for Maven seems more than a little buggy.) I have a test case which easily reproduces the problem. The following code generates a number of source files in the default package. If you try to compile ImplementingClass.java with javac, it will seem to pause for an inordinately long time. import java.io.File; import java.io.FileNotFoundException; import java.io.PrintStream; public class CodeGenerator { private final static String PATH = System.getProperty("java.io.tmpdir"); private final static int NUM_TYPES = 1000; public static void main(String[] args) throws FileNotFoundException { PrintStream interfacePs = new PrintStream(PATH + File.separator + "Interface.java"); PrintStream abstractClassPs = new PrintStream(PATH + File.separator + "AbstractClass.java"); PrintStream implementingClassPs = new PrintStream(PATH + File.separator + "ImplementingClass.java"); interfacePs.println("public interface Interface<T> {"); abstractClassPs.println("public abstract class AbstractClass<T> implements Interface<T> {"); implementingClassPs.println("public class ImplementingClass extends AbstractClass<Object> {"); for (int i=0; i<NUM_TYPES; i++) { String nodeName = "Node" + i; PrintStream nodePs = new PrintStream(PATH + File.separator + nodeName + ".java"); nodePs.printf("public class %s { }\n", nodeName); nodePs.close(); interfacePs.printf("void visit(%s node, T obj);%n", nodeName); abstractClassPs.printf("public void visit(%s node, T obj) { System.out.println(obj.toString()); }%n", nodeName); } interfacePs.println("}"); abstractClassPs.println("}"); implementingClassPs.println("}"); interfacePs.close(); abstractClassPs.close(); implementingClassPs.close(); } }

    Read the article

  • Space in DIV ??

    - by alex
    Hello all, Is it possible to avoid the spaces X & Y (see image)? There is no padding in CSS! <html> <head> <title>Prova WIDGET</title> <link rel="stylesheet" href="jquery-ui-1.8.1.custom/css/ui-lightness/jquery-ui-1.8.1.custom.css" type="text/css"> <script src="jquery-ui-1.8.1.custom/development-bundle/jquery-1.4.2.js" type="text/javascript"></script> <script src="jquery-ui-1.8.1.custom/js/jquery-ui-1.8.1.custom.min.js" type="text/javascript"></script> <script type="text/javascript"> $(themify); function themify(){ $("#pulsante").addClass("ui-button ui-button-text-only ui-widget ui-state-default ui-corner-all"); //ui-button-text } </script> <style>#test{display:none}</style> <script type="text/javascript"> function rendiVisibile(){ if(document.getElementById("test").style.display = "none"){ $("#test").css({"width":"100px","float":"right","text-align":"center"}); $("#test").show("slide",{},1000); } } </script> </head> <body> <h2 class="ui-widget-header">Tentativo widget con DIV</h2> <form action=""> <input type="button" value="Submit" id="pulsante" onclick="rendiVisibile()";><br/></br> <div id="test" class="ui-widget ui-widget-content ui-corner-all"> <h3 class="ui-widget-header ui-corner-all">CIAO</h3> <p class="ui-widget-content ui-corner-all">Un saluto</p> </div> </form> </body> </html>

    Read the article

  • Formtastic with Mongoid embedded_in relations

    - by miah
    Is there any quick way to make a form for embeds_many-embedded_in relation? I have the following: class Team include Mongoid::Document field :name, :type => String embeds_many :players end class Player include Mongoid::Document embedded_in :team, :inverse_of => :players field :name, :type => String end I want to create a form for team with embedded editing for players. Seen https://github.com/bowsersenior/formtastic_with_mongoid_tutorial but "TODO" there.

    Read the article

  • Loading data in constructors and not in constructors [JAVA]

    - by Richeve S. Bebedor
    i just want to know the difference between loading the data inside the constructor and loading the data outside the constructor but not inside any methods example: Loading inside constructor public class Model{ Object testobject; public Model(){ testobject=new Object(); } } VS example: Loading outside constructor public class Model{ Object testobject=new Object(); public Model(){ } }

    Read the article

  • Does Restlet support parsing URLs into calling methods with parameters?

    - by John C
    Take the following example. I have a resource public class HelloWorldResource extends ServerResource { @Get public String represent(String arg) { return "hello, world (from the cloud!)" + arg; } } That is mapped by router.attach("/hi/{message}", HelloWorldResource.class); Is it possible to configure the routing such that accessing /hi/somestuffhere will make restlet fill in the arg parameter in the represent method?

    Read the article

  • does the object creating a sub appdomain get instantiated in that sub appdomain?

    - by Eric
    does the object creating a sub appdomain get instantiated in that sub appdomain? I have an object that is in the main AppDomain and it is creating another AppDomain and it requires the calling class to be serializable and is creating an instance of the calling class in the new sub AppDomain. I'm wondering if that is how it is, or if there is a way that I can create the sub appDomain but still hold on to the original instantiation of the calling object in the main appDomain

    Read the article

  • Generate java code in Eclipse?

    - by drozzy
    Does anyone know what approach one can take to automatically generate Java source code, from for example an xml or json file, in eclipse? One great example of what I am thinking of doing is what Google Android sdk does: they have an R class generated automatically from the resources. Every time a resource file is saved in Eclipse R class is automatically regenerated. Thanks!

    Read the article

  • why make non-privileged methods?

    - by aharon
    I'm learning JavaScript, and I can't understand why you'd make methods that aren't 'privileged,' that is, that aren't defined in the constructor but rather the class' prototype. I understand the idea of encapsulation and all, but you never encapsulate parts of a class from the rest of it in most of the OO world.

    Read the article

  • Generic Dictionary C#

    - by pm_2
    I have a class that inherits from a generic dictionary as follows: Class myClass : System.Collections.Generic.Dictionary<int, Object> I have added a list of values to this in a particular order, but I now wish to change that order. Is there any way (without removing and re-adding) that I could effectively re-index the values; so change the object at index 1 to now be at index 10 for example? For example, this doesn't work: myClass[1].Index = 10;

    Read the article

  • Does jQuery or JavaScript have the concept of classes and objects?

    - by Prashant
    I found the following code somewhere, but I am not understanding the code properly. ArticleVote.submitVote('no');return false; Is ArticleVote a class and submitVote() a function of that class? Or what does the above code mean? And is there any concept of classes and objects in jQuery or in traditional JavaScript? How to create them? Please share some reference links or code.

    Read the article

  • issues with live function

    - by Do Good
    I am using the .live function to fire of a function aaa(). Unable to fire the function because code does not reach alert msg The structure of my html is body id="plants" form id= flower method="post" div class= "rose" div class= "red" ul id = "colors" li a li a li a Cuurently I am using $( 'body#plants form#flower div.rose div.red ul#colors li a' ).live('click', function(){ alert('code reaches'); aaa(); }); How can I get this to work?

    Read the article

  • Error Handling for Application in PHP

    - by Zubair1
    I was wondering if someone can show me a good way to handle errors in my PHP app, that i am also easily able to reuse in my codes. So far i have been using the following functions: Inline Errors function display_errors_for($fieldname) { global $errors; if (isset($errors[$fieldname])) { return '<label for="' .$fieldname. '" class="error">' . ucfirst($errors[$fieldname]). '</label>'; } else { return false; } } All Errrors function display_all_errors($showCounter = true) { global $errors; $counter = 0; foreach ($errors as $errorFieldName => $errorText) { if ($showCounter == true) { $counter++; echo '<li>' . $counter . ' - <label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } else { echo '<li><label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } } } I have a $errors = array(); defined on the top of my global file, so it is appended to all files. The way i use it is that if i encounter an error, i push a new error key/value to the $errors array holder, something like the following: if (strlen($username) < 3) { $errors['username'] = "usernames cannot be less then 3 characters."; } This all works great and all, But i wondering if some one has a better approach for this? with classes? i don't think i want to use Exceptions with try/catch seems like an overkill to me. I'm planning to make a new app, and i'll be getting my hands wet with OOP alot, though i have already made apps using OOP but this time i'm planning to go even deeper and use OOP approach more extensively. What i have in mind is something like this, though its just a basic class i will add further detail to it as i go deeper and deeper in my app to see what it needs. class Errors { public $errors = array(); public function __construct() { // Initialize Default Values // Initialize Methods } public function __destruct() { //nothing here too... } public function add($errorField, $errorDesc) { if (!is_string($errorField)) return false; if (!is_string($errorDesc)) return false; $this->errors[$errorField] = $errorDesc; } public function display($errorsArray) { // code to iterate through the array and display all errors. } } Please share your thoughts, if this is a good way to make a reusable class to store and display errors for an entire app, or is getting more familiar with exceptions and try/catch my only choice?

    Read the article

  • Simplest way to flatten document to a view in RavenDB

    - by degorolls
    Given the following classes: public class Lookup { public string Code { get; set; } public string Name { get; set; } } public class DocA { public string Id { get; set; } public string Name { get; set; } public Lookup Currency { get; set; } } public class ViewA // Simply a flattened version of the doc { public string Id { get; set; } public string Name { get; set; } public string CurrencyName { get; set; } // View just gets the name of the currency } I can create an index that allows client to query the view as follows: public class A_View : AbstractIndexCreationTask<DocA, ViewA> { public A_View() { Map = docs => from doc in docs select new ViewA { Id = doc.Id, Name = doc.Name, CurrencyName = doc.Currency.Name }; Reduce = results => from result in results group on new ViewA { Id = result.Id, Name = result.Name, CurrencyName = result.CurrencyName } into g select new ViewA { Id = g.Key.Id, Name = g.Key.Name, CurrencyName = g.Key.CurrencyName }; } } This certainly works and produces the desired result of a view with the data transformed to the structure required at the client application. However, it is unworkably verbose, will be a maintenance nightmare and is probably fairly inefficient with all the redundant object construction. Is there a simpler way of creating an index with the required structure (ViewA) given a collection of documents (DocA)? FURTHER INFORMATION The issue appears to be that in order to have the index hold the data in the transformed structure (ViewA), we have to do a Reduce. It appears that a Reduce must have both a GROUP ON and a SELECT in order to work as expected so the following are not valid: INVALID REDUCE CLAUSE 1: Reduce = results => from result in results group on new ViewA { Id = result.Id, Name = result.Name, CurrencyName = result.CurrencyName } into g select g.Key; This produces: System.InvalidOperationException: Variable initializer select must have a lambda expression with an object create expression Clearly we need to have the 'select new'. INVALID REDUCE CLAUSE 2: Reduce = results => from result in results select new ViewA { Id = result.Id, Name = result.Name, CurrencyName = result.CurrencyName }; This prduces: System.InvalidCastException: Unable to cast object of type 'ICSharpCode.NRefactory.Ast.IdentifierExpression' to type 'ICSharpCode.NRefactory.Ast.InvocationExpression'. Clearly, we also need to have the 'group on new'. Thanks for any assistance you can provide. (Note: removing the type (ViewA) from the constructor calls has no effect on the above)

    Read the article

  • Naming member functions/methods with a single underscore, good style or bad?

    - by Extrakun
    In some languages where you cannot override the () operator, I have seen methods with a single underscore, usually for 'helper' classes. Something likes this: class D10 { public function _() { return rand(1,10); } } Is it better to have the function called Roll()? Is a underscore fine? After all, there is only one function, and it removes the need to look up the name of the class. Any thoughts?

    Read the article

< Previous Page | 648 649 650 651 652 653 654 655 656 657 658 659  | Next Page >