Search Results

Search found 7129 results on 286 pages for 'battery usage'.

Page 54/286 | < Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >

  • Correct usage of "<T extends SuperClass>"

    - by yusaku
    I am not familiar with "Generics". Is it a correct use of "<T extends SuperClass>" ? And do you agree that the codes after using generics are better? Before using Generics ================================================= public abstract class SuperSample { public void getSomething(boolean isProcessA) { doProcessX(); if(isProcessA){ doProcessY(new SubASample()); }else{ doProcessY(new SubBSample()); } } protected abstract void doProcessX(); protected void doProcessY(SubASample subASample) { // Nothing to do } protected void doProcessY(SubBSample subBSample) { // Nothing to do } } public class SubASample extends SuperSample { @Override protected void doProcessX() { System.out.println("doProcessX in SubASample"); } @Override protected void doProcessY(SubASample subASample) { System.out.println("doProcessY in SubASample"); } } public class Sample { public static void main(String[] args) { SubASample subASample = new SubASample(); subASample.getSomething(true); } } After using Generics ================================================= public abstract class SuperSample { public void getSomething(boolean isProcessA) { doProcessX(); if(isProcessA){ doProcessY(new SubASample()); }else{ doProcessY(new SubBSample()); } } protected abstract void doProcessX(); protected abstract <T extends SuperSample> void doProcessY(T subSample); } public class SubASample extends SuperSample { @Override protected void doProcessX() { System.out.println("doProcessX in SubASample"); } @Override protected <T extends SuperSample> void doProcessY(T subSample) { System.out.println("doProcessY in SubASample"); } } public class Sample { public static void main(String[] args) { SubASample subASample = new SubASample(); subASample.getSomething(true); } }

    Read the article

  • commad design pattern usage

    - by sagie
    Hi. I've read 3 descriptions of the command design pattern: wikipedia, dofactory and source making. In all of them, the UML shows a relation between the client to the receiver & the concrete command, but no relation to the invoker. But in all 3 examples the client is the one that initiates the invoker and call its Execute method. I think that should be a relation to the invoker as well. Am I missing somthing in here? Maybe even a basic UML knowladge?

    Read the article

  • Usage patterns/use cases for DI or when to start using it

    - by Fabian
    I'm not sure for which use cases one should to use DI in the application. I know that injecting services like PlaceService or CalculationService etc fits very well but should I also create my domain objects with DI like a User? What is if the User has only one constructor which requires a first and lastname. Is this solveable with DI? Should I use DI to create the instances for Set/List interfaces or is this pure overkill? I use guice primarily.

    Read the article

  • Hibernate many-to-one - bad usage?

    - by DaveA
    Just trying out Hibernate (with Annotations) and I'm having problems with my mappings. I have two entity classes, AudioCD and Artist. @Entity public class AudioCD implements CatalogItem { @Id @GeneratedValue(strategy = GenerationType.AUTO) private int id; private String title; @ManyToOne(cascade = { CascadeType.ALL }, optional = false) private Artist artist; .... } @Entity @Table(uniqueConstraints = { @UniqueConstraint(columnNames = { "name" }) }) public class Artist { @Id @GeneratedValue(strategy = GenerationType.AUTO) private int id; @Column(nullable = false) private String name; ..... } I get AudioCD objects from an external source. When I try to persist the AudioCD the Artist gets persisted as well, just like I want to happen. If I try persisting another different CD, but Artist already exists I get errors due to constraint violations. I want Hibernate to recognise that the Artist already exists and shouldn't be inserted again. Can this be done via annotations? Or do I have to manage the persistence of the AudioCD and Artist seperately?

    Read the article

  • Android @Override usage

    - by BahaiResearch.com
    (Newbie to Java, old time C# guy.) I have noticed a lot of the use of @Override in Android example code. I thought that all Java methods were by default "Virutal"? What then does @Override do? Example: private class HelloWebViewClient extends WebViewClient { @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { view.loadUrl(url); return true; } }

    Read the article

  • C# ApplicationContext usage

    - by rd42
    Apologies if my terminology is off, I'm new to C#. I'm trying to use an ApplicationContext file to store mysql conn values, like dbname, username, password. The class with mysql conn string is "using" the namespace for the ApplicationContext, but when I print out the connection string, the values are making it. A friend said, "I'm not initializing it" but couldn't stay to expand on what "it" was. and the "Console.WriteLine("1");" in ApplicationContext.cs never shows up. Do I need to create an ApplicationContext object and the call Initialize() on that object? Thanks for any help. ApplicationContext.cs: namespace NewApplication.Context { class ApplicationContext { public static string serverName; public static string username; public static string password; public static void Initialize() { //need to read through config here try { Console.WriteLine("1"); XmlDocument xDoc = new XmlDocument(); xDoc.Load(".\\Settings.xml"); XmlNodeList serverNodeList = xDoc.GetElementsByTagName("DatabaseServer"); XmlNodeList usernameNodeList = xDoc.GetElementsByTagName("UserName"); XmlNodeList passwordNodeList = xDoc.GetElementsByTagName("Password"); } catch (Exception ex) { // MessageBox.Show(ex.ToString()); //TODO: Future write to log file username = "user"; password = "password"; serverName = "localhost"; } } } } MySQLManager.cs: note: dbname is the same as the username as you'll see in the code, I copied this from a friend who does that. using System; using System.Collections.Generic; using System.Linq; using System.Text; using MySql.Data; using MySql.Data.MySqlClient; using NewApplication.Context; namespace NewApplication.DAO { class MySQLManager { private static MySqlConnection conn; public static MySqlConnection getConnection() { if (conn == null || conn.State == System.Data.ConnectionState.Closed) { string connStr = "server=" + ApplicationContext.serverName + ";user=" + ApplicationContext.username + ";database=" + ApplicationContext.username + ";port=3306;password=" + ApplicationContext.password + ";"; conn = new MySqlConnection(connStr); try { Console.WriteLine("Connecting to MySQL... "); Console.WriteLine("Connection string: " + connStr + "\n"); conn.Open(); // Perform databse operations // conn.Close(); } catch (Exception ex) { Console.WriteLine(ex.ToString()); } } return conn; } } } and, thanks for still reading, this is the code that uses the two previous files: class LogDAO { MySqlConnection conn; public LogDAO() { conn = MySQLManager.getConnection(); } Thank you, rd42

    Read the article

  • Question about memory usage

    - by sudo rm -rf
    Hi there. I have the following method: +(NSMutableDictionary *)getTime:(float)lat :(float)lon { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; NSMutableDictionary *dictionary = [[NSMutableDictionary alloc] init]; [dictionary setObject:hour forKey:@"hour"]; [dictionary setObject:minute forKey:@"minute"]; [dictionary setObject:ampm forKey:@"ampm"]; return dictionary; } A lot of the method is chopped off, so I think I need the pool for some other stuff in the method. Here's my question. I know that I need to release the following objects: [dictionary release]; [pool release]; However, I can't release the dictionary before I return it, but as soon as I return it the rest of the method isn't performed. What should I do?

    Read the article

  • Implementing a kext that intercepts file system usage.

    - by UraN
    Hi, how do most of antivirus software block file system io in case of an infected file? I suppose all the magic resides in some custom kext to do that. Can anyone point me to some topics on this? Some working example would also be great. I've read apple docs about kext development, but mostly it's all about hardware drivers and i could not find what i need. Thanx.

    Read the article

  • Proper usage of Java Weak Reference in case of nested collections

    - by Tong Wang
    I need to define a weak reference Map, whose value is a Set. I use Google collections' MapMaker, like this: Map<Class<? extends Object>, Set<Foo>> map = new MapMaker().weakKeys().weakValues().makeMap(); So, for Set<Foo>, can I use a normal HashSet? Or, do I have to create a weak HashSet, like this: Collections.newSetFromMap(new WeakHashMap<Foo, Boolean>()); And why? Another question, the key of my map is Class objects, when will a Class object become weakly reachable? In other words, what is the lifetime of a Class object? Thanks.

    Read the article

  • Question About id and Delegate Usage in Obj-C

    - by Stunner
    Ey guys, I am wondering what the following line of code is doing: @property (assign, nonatomic) id <CoursePlannerDelegate> delegate; Namely I am wondering about this portion of the line: id <CoursePlannerDelegate> delegate; It also shows up in other places: @interface CategoryAddViewController : UIViewController { UITextField *nameField, *weightField; double maxWeight; //The maximum weight that can be allocated to this Category (max value of 100) id <CategoryAddDelegate> delegate; //A Course Planner TVC } Any help appreciated, thanks in advance!

    Read the article

  • Proper usage of double and single quotes?

    - by Phox
    I'm talking about the performance increase here. From all I know you can echo variables in double quotes ("), like so: <?php echo "You are $yourAge years old"; ?> But single quotes will just return You are $yourAge years old. But what about performance differences? I've always gone by the rule that single quotes are faster because the PHP interpreter doesn't have to search through the string for variables. But I'm seeing more and more blog and forum posts on the web saying differently. Does anyone actually have any information on this subject? Perhaps benchmark tests or something?

    Read the article

  • Semantic #region usage

    - by Luca
    What's your opinion about using #region folding using application semantic, instead of folding for "syntax". For example: #region Application Loop #region User Management #region This Kinf of stuffs instead of #region Private Routines #region Public Properties #region ThisRoutine // (Yes, I've seen this also!) In this logic, I'm starting fold even routine bodies. I'm starting to love #region directive (even using #pragma region when using C++!).

    Read the article

  • Concurrent usage of table causing issues

    - by Sven
    Hello In our current project we are interfacing with a third party data provider. They need to insert data in a table of ours. This inserting can be frequent every 1 min, every 5min, every 30, depends on the amount of new data they need to provide. The use the isolation level read committed. On our end we have an application, windows service, that calls a webservice every 2 minutes to see if there is new data in this table. Our isolation level is repeatable read. We retrieve the records and update a column on these rows. Now the problem is that sometimes this third party provider needs to insert a lot of data, let's say 5000 records. They do this per transaction (5rows per transaction), but they don't close the connection. They do one transaction and then the next untill all records are inserted. This caused issues for our process, we receive a timeout. If this goes on for a long time the database get's completely unstable. For instance, they maybe stopped, but the table somehow still stays unavailable. When I try to do a select on the table, I get several records but at a certain moment I don't get any response anymore. It just says retrieving data but nothing comes anymore until I get a timeout exception. Only solution is to restart the database and then I see the other records. How can we solve this. What is the ideal isolation level setting in this scenario?

    Read the article

  • What is the purpose of this delegate usage?

    - by Kev
    Whilst poking around some code in .NET Reflector in an app I don't have the source code for I found this: if (DeleteDisks) { using (List<XenRef<VDI>>.Enumerator enumerator3 = list.GetEnumerator()) { MethodInvoker invoker2 = null; XenRef<VDI> vdiRef; while (enumerator3.MoveNext()) { vdiRef = enumerator3.Current; if (invoker2 == null) { // // Why do this? // invoker2 = delegate { VDI.destroy(session, vdiRef.opaque_ref); }; } bestEffort(ref caught, invoker2); } } } if (caught != null) { throw caught; } private static void bestEffort(ref Exception caught, MethodInvoker func) { try { func(); } catch (Exception exception) { log.Error(exception, exception); if (caught == null) { caught = exception; } } } Why not call VDI.destroy() directly. Is this just a way of wrapping the same pattern of try { do something } catch { log error } if it's used a lot?

    Read the article

  • Read vs Find -- Cakephp Usage

    - by Michael
    Hi all, I was reading through a book on CakePhp Application structure, and came across both the read and find functions. I've always only used find -- when would a read be appropriate? Examples appreciated. Thanks!

    Read the article

  • usage of intval & real_escape_string when sanitizing integers

    - by paulus
    dear All. I'm using integer PKs in some tables of mysql database. Before input from PHP script, I am doing some sanitizing, which includes intval($id) and $mysqli-real_escape_string(). The queries are quite simple insert into `tblproducts`(`supplier_id`,`description`) values('$supplier_id','$description') In this example, $description goes through real_escape_string(), while $supplier_id only being intval()'ed. I'm just curious, if there're any situations, when I need to apply both intval and real_escape_string to integer I'm inserting into DB? So basically do I really need to use? $supplier_id = intval($mysqli->real_escape_string($supplier_id)); Thank you.

    Read the article

  • Handling large datasets with PHP/Drupal

    - by jo
    Hi all, I have a report page that deals with ~700k records from a database table. I can display this on a webpage using paging to break up the results. However, my export to PDF/CSV functions rely on processing the entire data set at once and I'm hitting my 256MB memory limit at around 250k rows. I don't feel comfortable increasing the memory limit and I haven't got the ability to use MySQL's save into outfile to just serve a pre-generated CSV. However, I can't really see a way of serving up large data sets with Drupal using something like: $form = array(); $table_headers = array(); $table_rows = array(); $data = db_query("a query to get the whole dataset"); while ($row = db_fetch_object($data)) { $table_rows[] = $row->some attribute; } $form['report'] = array('#value' => theme('table', $table_headers, $table_rows); return $form; Is there a way of getting around what is essentially appending to a giant array of arrays? At the moment I don't see how I can offer any meaningful report pages with Drupal due to this. Thanks

    Read the article

  • ASP.NET MVC2 - usage of LINQ-generated class (validation problem)

    - by ile
    There are few things not clear to me about ASP.NET MV2. In database I have table Contacts with several fields, and there is an additional field XmlFields of which type is xml. In that field are stored additional description fields. There are 4 classes: Contact class which corresponds to Contact table and is defined by default when creating LINQ classes ContactListView class which inherits Contact class and has some additional properties ContactXmlView class that contains fields from XmlFields field ContactDetailsView class which merges ContactListView and ContactXmlView into one class and this one is used to display data in view pages ContactListView class has re-defined some properties from Contact class (so that I can add [Required] filter used for validation) - but I get warning message: 'ObjectTest.Models.Contacts.ContactListView.FirstName' hides inherited member 'SA.Model.Contact.FirstName'. Use the new keyword if hiding was intended. ContactDetailsView class is also used in a form when creating new contact and adding it to database. I am not sure if this is correct way, and the warning message confuses me a bit. Any advise about this? Thanks, Ile EDIT According to Jakob's instructions I tried it from scratch: [MetadataType(typeof(Person_Validation))] public partial class Person { } public class Person_Validation { [Required] string FirstName { get; set; } [Required] string LastName { get; set; } [Required] int Age { get; set; } } In Controller I have this: [HttpPost] public ActionResult Create(Person person, FormCollection collection) { if (ModelState.IsValid) { try { personRepository.Add(person); personRepository.Save(); } catch { return View(person); } } return RedirectToAction("Index"); } View: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<Validate.Models.Person>" %> <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> Create </asp:Content> <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> <h2>Create</h2> <% using (Html.BeginForm()) {%> <%= Html.ValidationSummary(true) %> <fieldset> <legend>Fields</legend> <div class="editor-label"> <%= Html.LabelFor(model => model.FirstName) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.FirstName) %> <%= Html.ValidationMessageFor(model => model.FirstName) %> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.LastName) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.LastName) %> <%= Html.ValidationMessageFor(model => model.LastName) %> </div> <div class="editor-label"> <%= Html.LabelFor(model => model.Age) %> </div> <div class="editor-field"> <%= Html.TextBoxFor(model => model.Age) %> <%= Html.ValidationMessageFor(model => model.Age) %> </div> <p> <input type="submit" value="Create" /> </p> </fieldset> <% } %> <div> <%= Html.ActionLink("Back to List", "Index") %> </div> </asp:Content> When posting new person with no values, nothing happens (page is just reloaded). When posting with some values, person is added to db. I have no idea what am I doing wrong.

    Read the article

  • boost::this_thread::disable_interruption usage confusion

    - by Evgenii
    boost/thread/pthread/shared_mutex.hpp contains this code: ... #include <boost/thread/detail/thread_interruption.hpp> ... class shared_mutex { ... void lock_shared() { boost::this_thread::disable_interruption do_not_disturb; boost::mutex::scoped_lock lk(state_change); while(state.exclusive || state.exclusive_waiting_blocked) { shared_cond.wait(lk); } ++state.shared_count; } ... }; but boost/thread/detail/thread_interruption.hpp does not contain implementation of disable_interruption, only the prototype. in boost_1_42_0/libs/thread/src/pthread we don't have the implementation too how does it work!???

    Read the article

< Previous Page | 50 51 52 53 54 55 56 57 58 59 60 61  | Next Page >