Search Results

Search found 14034 results on 562 pages for 'interface inheritance'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 201/562 | < Previous Page | 197 198 199 200 201 202 203 204 205 206 207 208  | Next Page >

  • What's the standard way to organize the contents of Java packages -- specifically the location of in

    - by RenderIn
    I suppose this could go for many OO languages. I'm building my domain objects and am not sure where the best place is for the interfaces & abstract classes. If I have a pets package with various implementations of the APet abstract class: should it live side-by-side with them or in the parent package? How about interfaces? It seems like they almost have to live above the implementations in the parent package, since there could potentially be other subpackages which implement it, while there seems to be a stronger correlation between one abstract class and a subpackage. e.g. com.foo com.foo.IConsumer (interface) com.foo.APet (abstract) com.foo.pets.Dog extends APet implements IConsumer OR com.foo com.foo.IConsumer (interface) com.foo.pets.APet (abstract) com.foo.pets.Dog extends APet implements IConsumer or something else?

    Read the article

  • Objective-C categories: Can I add a property for a method not in my category?

    - by Squeegy
    I want to use a category to make a method on the original class available as a property as well. Class A: @interface ClassA - (NSString*)foo; @end Class A category @interface ClassA (Properties) - (void)someCategoryMethod; @property (nonatomic, readonly) NSString *foo; @end Now when I do this, it seems to work, but it gives me warnings because I am not synthesizing the property in my category implementation. How do I tell the compiler everything is actually just fine since the original class synthesizes the property for me?

    Read the article

  • Generic WithEvents

    - by serhio
    Error: 'WithEvents' variables can only be typed as classes, interfaces or type parameters with class constraints Background: Public Class Tadpole(Of T As IVisibleChanged, P As IVisibleChanged) Private WithEvents _Tad As T ' ERROR ' Private WithEvents _Pole As P ' ERROR ' Public Property Tad() As T ... Public Property Pole() As P ... End Class ''' IVisibleChanged ''' Public Interface IVisibleChanged Property Visible() As Boolean Event VisibleChanged As EventHandler End Interface Workaround: a. Use AddHandler to handle events defined in a structure. EDIT b. use Private WithEvents _Tad AsIVisibleChanged (M.A. Hanin) c. ?

    Read the article

  • IRequiresSessionState - how do I use it?

    - by Praesagus
    I need to be able to change when I can see session state. I found out about the IRequiresSessionState Marker Interface, but have not been able to figure out how to use it. I think I may be missing something obvious. Can one of you C# guru's give me a quick 1-2-3 step through? (e.g. 1 create a new class, 2. put public interface IRequiresSessionState in it. 3. Use IRequiresSessionState('abra_cadabra') to change the value.). Thank you for your help.

    Read the article

  • Correct way to make datasources/resources a deploy-time setting

    - by Draemon
    I have a web-app that requires two settings: A JDBC datasource A string token I desperately want to be able to deploy one .war to various different containers (jetty,tomcat,gf3 minimum) and configure these settings at application level within the container. My code does this: InitialContext ctx = new InitialContext(); Context envCtx = (javax.naming.Context) ctx.lookup("java:comp/env"); token = (String)envCtx.lookup("token"); ds = (DataSource)envCtx.lookup("jdbc/datasource") Let's assume I've used the glassfish management interface to create two jdbc resources: jdbc/test-datasource and jdbc/live-datasource which connect to different copies of the same schema, on different servers, different credentials etc. Say I want to deploy this to glassfish with and point it at the test datasource, I might have this in my sun-web.xml: ... <resource-ref> <res-ref-name>jdbc/datasource</res-ref-name> <jndi-name>jdbc/test-datasource</jndi-name> </resource-ref> ... but sun-web.xml goes inside my war, right? surely there must be a way to do this through the management interface Am I even trying to do the right thing? Do other containers make this any easier? I'd be particularly interested in how jetty 7 handles this since I use it for development. EDIT Tomcat has a reasonable way to do this: Create $TOMCAT_HOME/conf/Catalina/localhost/webapp.xml with: <?xml version="1.0" encoding="UTF-8"?> <Context antiResourceLocking="false" privileged="true"> <!-- String resource --> <Environment name="token" value="value of token" type="java.lang.String" override="false" /> <!-- Linking to a global resource --> <ResourceLink name="jdbc/datasource1" global="jdbc/test" type="javax.sql.DataSource" /> <!-- Derby --> <Resource name="jdbc/datasource2" type="javax.sql.DataSource" auth="Container" driverClassName="org.apache.derby.jdbc.EmbeddedDataSource" url="jdbc:derby:test;create=true" /> <!-- H2 --> <Resource name="jdbc/datasource3" type="javax.sql.DataSource" auth="Container" driverClassName="org.h2.jdbcx.JdbcDataSource" url="jdbc:h2:~/test" username="sa" password="" /> </Context> Note that override="false" means the opposite. It means that this setting can't be overriden by web.xml. I like this approach because the file is part of the container configuration not the war, but it's not part of the global configuration; it's webapp specific. I guess I expect a bit more from glassfish since it is supposed to have a full web admin interface, but I would be happy enough with something equivalent to the above.

    Read the article

  • Building highly scalable web services

    - by christopher-mccann
    My team and I are in the middle of developing an application which needs to be able to handle pretty heavy traffic. Not facebook level but in the future I would like to be able to scale to that without massive code re-writes. My thought was to modularise out everything into seperate services with their own interfaces. So for example messaging would have a messaging interface that might have send and getMessages() as methods and then the PHP web app would simply query this interface through soap or curl or something like that. The messaging application could then be any kind of application so a Java application or Python or whatever was suitable for that particular functionality with its own seperate database shard. Is this a good approach?

    Read the article

  • Why is the C# SerializedAttribute is sealed?

    - by ahmet alp balkan
    I was trying to create an attribute that implies [Serializable] but I noticed that this SerializableAttribute class is sealed. In Java it was possible to create an interface (say, MyInterface) that is inherited from Serializable interface and so all the subclasses of MyInterface would also be serializable, even its sub-sub classes would be so. Let's say I am creating an ORM and I want customers to annotate their entity classes as [DatabaseEntity] but in order to make sure that entities are serializable, I also need to ask them to attribute their classes with extra [Serializable] which does not look quite compact and neat. I am wondering why SerializableAttribute class is sealed and why has Inherited=false which implies that subclasses of serializable class will not be serializable unless it is explicitly stated. What motives are behind these design choices?

    Read the article

  • Regarding Debugging in Xcode

    - by user185590
    #import <Foundation/Foundation.h> @interface ClassA : NSObject { int x; } -(void) initVar; @end @implementation ClassA -(void) initVar { x = 100; } @end @interface ClassB : ClassA { int y; } -(void) initVar; -(void) printVar; @end @implementation ClassB -(void) initVar { x = 200; y = 300; } - (void) printVar { NSLog(@"x= %i", x ); NSLog(@"y= %i", y); } @end int main (int argc, const char * argv[]) { NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init]; ClassB * b = [[ClassB alloc] init]; [b initVar]; [b printVar]; [b release]; [pool drain]; return 0; }

    Read the article

  • Web app - Biometric system connection

    - by DMin
    Hi, I will be developing an application for a club where they will have visitors use biometric systems(finger print) or magnetic cards to mark their attendance. This application is planned as a web app, made using PHP/MySQL/Javascript. It does a lot of other things as well. What I wanted to find out is how is the interface between Biometric/Megnetic Card systems to a web app done? I've never worked on this and am hoping if someone who has experience with this can throw some light on this as to how this could be accomplished. Any pointers will be appreciated. (I'm afraid there's got to be some form of application installed on a pc that would interface with the hardware and probably makes calls to the web app. But, if there was a way to connect it to the web app directly, then the app would be easy to deploy to any location with minimal installation.) Thanks! :)

    Read the article

  • Go - Using a container/heap to implement a priority queue

    - by Seth Hoenig
    In the big picture, I'm trying to implement Dijkstra's algorithm using a priority queue. According to members of golang-nuts, the idiomatic way to do this in Go is to use the heap interface with a custom underlying data structure. So I have created Node.go and PQueue.go like so: //Node.go package pqueue type Node struct { row int col int myVal int sumVal int } func (n *Node) Init(r, c, mv, sv int) { n.row = r n.col = c n.myVal = mv n.sumVal = sv } func (n *Node) Equals(o *Node) bool { return n.row == o.row && n.col == o.col } And PQueue.go: // PQueue.go package pqueue import "container/vector" import "container/heap" type PQueue struct { data vector.Vector size int } func (pq *PQueue) Init() { heap.Init(pq) } func (pq *PQueue) IsEmpty() bool { return pq.size == 0 } func (pq *PQueue) Push(i interface{}) { heap.Push(pq, i) pq.size++ } func (pq *PQueue) Pop() interface{} { pq.size-- return heap.Pop(pq) } func (pq *PQueue) Len() int { return pq.size } func (pq *PQueue) Less(i, j int) bool { I := pq.data.At(i).(Node) J := pq.data.At(j).(Node) return (I.sumVal + I.myVal) < (J.sumVal + J.myVal) } func (pq *PQueue) Swap(i, j int) { temp := pq.data.At(i).(Node) pq.data.Set(i, pq.data.At(j).(Node)) pq.data.Set(j, temp) } And main.go: (the action is in SolveMatrix) // Euler 81 package main import "fmt" import "io/ioutil" import "strings" import "strconv" import "./pqueue" const MATSIZE = 5 const MATNAME = "matrix_small.txt" func main() { var matrix [MATSIZE][MATSIZE]int contents, err := ioutil.ReadFile(MATNAME) if err != nil { panic("FILE IO ERROR!") } inFileStr := string(contents) byrows := strings.Split(inFileStr, "\n", -1) for row := 0; row < MATSIZE; row++ { byrows[row] = (byrows[row])[0 : len(byrows[row])-1] bycols := strings.Split(byrows[row], ",", -1) for col := 0; col < MATSIZE; col++ { matrix[row][col], _ = strconv.Atoi(bycols[col]) } } PrintMatrix(matrix) sum, len := SolveMatrix(matrix) fmt.Printf("len: %d, sum: %d\n", len, sum) } func PrintMatrix(mat [MATSIZE][MATSIZE]int) { for r := 0; r < MATSIZE; r++ { for c := 0; c < MATSIZE; c++ { fmt.Printf("%d ", mat[r][c]) } fmt.Print("\n") } } func SolveMatrix(mat [MATSIZE][MATSIZE]int) (int, int) { var PQ pqueue.PQueue var firstNode pqueue.Node var endNode pqueue.Node msm1 := MATSIZE - 1 firstNode.Init(0, 0, mat[0][0], 0) endNode.Init(msm1, msm1, mat[msm1][msm1], 0) if PQ.IsEmpty() { // make compiler stfu about unused variable fmt.Print("empty") } PQ.Push(firstNode) // problem return 0, 0 } The problem is, upon compiling i get the error message: [~/Code/Euler/81] $ make 6g -o pqueue.6 Node.go PQueue.go 6g main.go main.go:58: implicit assignment of unexported field 'row' of pqueue.Node in function argument make: *** [all] Error 1 And commenting out the line PQ.Push(firstNode) does satisfy the compiler. But I don't understand why I'm getting the error message in the first place. Push doesn't modify the argument in any way.

    Read the article

  • Writing SDK documentation, need useful beginner tutorials

    - by David Rutten
    I'm currently writing SDK documentation for one of our products, but for obvious reasons I don't want to talk about the essentials of OOP. Does anyone know any good online teaching material that explain (aimed at absolute beginners) concepts such as classes, inheritance, constructors, instances etc.? Preferably urls that are likely to survive for a couple of years to come... It's a DotNET SDK and we're including only VB and C# samples, so C++ or Delphi or Lisp material is not that useful.

    Read the article

  • iPhone: how do I set up a clear window-size "blocker view"?

    - by Ben
    I feel like this should be obvious to me, but for some reason I can't figure this out. I have a navigation interface with nav bar, tool bar, and primary view. Sometimes the user takes an action that causes a progress indicator to appear in the middle of the view. While the progress indicator (which is a custom UIView) in spinning in the middle, I want no touch input to be allowed to go to any of the underlying interface (main view, nav bar, toolbar, etc). But this doesn't seem trivial. I've tried (and failed) to create a simple view whose only job is to swallow touch input and use it as a window subview-- no dice, it never gets the touch events (and yes, it does have userInteractionEnabled). I've tried to bolt it on as a transparent modal view controller, but those don't seem to ever be transparent. Thoughts? What am I missing? Thanks!

    Read the article

  • What ways are there for cleaning an R environment from objects?

    - by Tal Galili
    I know I can use ls() and rm() to see and remove objects that exist in my environment. However, when dealing with "old" .RData file, one needs to sometimes pick an environment a part to find what to keep and what to leave out. What I would like to do, is to have a GUI like interface to allow me to see the objects, sort them (for example, by there size), and remove the ones I don't need (for example, by a check-box interface). Since I imagine such a system is not currently implemented in R, what ways do exist? What do you use for cleaning old .RData files? Thanks, Tal

    Read the article

  • How to change font size in a pickerview?

    - by user183804
    I'm fairly new to iPhone programming and am trying to implement a double-component PickerView. At this point the picker works fine in terms of taking user input, created with Interface Builder. However, I need to change the font size to accommodate the text length in each column. I very much would appreciate any link to a straightforward method to creating a multi-component picker with an adjustable font size. Seems like it is not possible if Interface Builder is used to create the picker. So far I have not found any code links that address this issue in detail. Thanks in advance.

    Read the article

  • What features would you like to see removed from C++?

    - by Justin Ethier
    This question was inspired by what-features-would-you-like-to-see-added-to-c. anBasically, C++ is a great general-purpose language. But perhaps too general and feature-rich... multiple inheritance, operator overloading, manual memory management, templates, smart pointers, virtual destructors, legacy frameworks (think MFC), and I could just go on. Is there any one feature / aspect of C++ that you would like taken away, to make our lives easier as C++ developers? One feature per answer, please.

    Read the article

  • When I really need to use [NSThread sleepForTimeInterval:1];

    - by Timbo
    Hi there, I have a program that needs to use sleep. Like really needs to. In lieu of spending ages explaining why, suffice to say that it needs it. Now I'm told to split off my code into a separate thread if it requires sleep so I don't lose interface responsiveness, so I've started learning how to use NSThread. I've created a brand new program that is conceptual so to solve the issue for this example will help me in my real program. Short story is I have a class, it has instance variables and I need a loop with a sleep to be depended on the value of that instance variable. Here's what I've put together anyway, your help is very much appreciated :) Cheers Tim /// Start Test1ViewController.h /// #import <UIKit/UIKit.h> @interface Test1ViewController : UIViewController { UILabel* label; } @property (assign) IBOutlet UILabel *label; @end /// End Test1ViewController.h /// /// Start Test1ViewController.m /// #import "Test1ViewController.h" #import "MyClass.h" @implementation Test1ViewController @synthesize label; - (void)viewDidAppear:(BOOL)animated { [super viewDidAppear:animated]; label.text = @"1"; [NSThread detachNewThreadSelector:@selector(backgroundProcess) toTarget:self withObject:nil]; } - (void)backgroundProcess { NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init]; // Create an instance of a class that will eventually store a whole load of variables MyClass *aMyClassInstance = [MyClass new]; [aMyClassInstance createMyClassInstance:(@"Timbo")]; while (aMyClassInstance.myVariable--) { NSLog(@"blah = %i",aMyClassInstance.myVariable); label.text = [NSString stringWithFormat:@"blah = %d", aMyClassInstance.myVariable]; //how do I pass the new value out to the updateLabel method, or reference aMyClassInstance.myVariable? [self performSelectorOnMainThread:@selector(updateLabel) withObject:nil waitUntilDone:NO]; //the sleeping of the thread is absolutely mandatory and must be worked around. The whole point of using NSThread is so I can have sleeps [NSThread sleepForTimeInterval:1]; } [pool release]; } - (void)updateLabel {label.text = [NSString stringWithFormat:@"blah = %d", aMyClassInstance.myVariable]; // be nice if i could } - (void)didReceiveMemoryWarning {[super didReceiveMemoryWarning];} - (void)viewDidUnload {} - (void)dealloc {[super dealloc];} @end /// End Test1ViewController.m /// /// Start MyClass.h /// #import <Foundation/Foundation.h> @interface MyClass : NSObject { NSString* name; int myVariable; } @property int myVariable; @property (assign) NSString *name; - (void) createMyClassInstance: (NSString*)withName; - (int) changeVariable: (int)toAmount; @end /// End MyClass.h /// /// Start MyClass.h /// #import "MyClass.h" @implementation MyClass @synthesize name, myVariable; - (void) createMyClassInstance: (NSString*)withName{ name = withName; myVariable = 10; } - (int) changeVariable: (int)toAmount{ myVariable = toAmount; return toAmount; } @end /// End MyClass.h ///

    Read the article

  • C# - calling ext. DLL function containing Delphi "variant record" parameter

    - by CaldonCZE
    Hello, In external (Delphi-created) DLL I've got the following function that I need to call from C# application. function ReadMsg(handle: longword; var Msg: TRxMsg): longword; stdcall; external 'MyDll.dll' name 'ReadMsg'; The "TRxMsg" type is variant record, defined as follows: TRxMsg = record case TypeMsg: byte of 1: (accept, mask: longword); 2: (SN: string[6]); 3: (rx_rate, tx_rate: word); 4: (rx_status, tx_status, ctl0, ctl1, rflg: byte); end; In order to call the function from C#, I declared auxiliary structure "my9Bytes" containing array of bytes and defined that it should be marshalled as 9 bytes long array (which is exactly the size of the Delphi record). private struct my9Bytes { [MarshalAs(UnmanagedType.ByValArray, ArraySubType = UnmanagedType.U1, SizeConst = 9)] public byte[] data; } Then I declared the imported "ReadMsg" function, using the "my9bytes" struct. [DllImport("MyDll.dll")] private static extern uint ReadMsg(uint handle, ref my9Bytes myMsg); I can call the function with no problem... Then I need to create structure corresponding to the original "TRxMsg" variant record and convert my auxiliary "myMsg" array into this structure. I don't know any C# equivalent of Delphi variant array, so I used inheritance and created the following classes. public abstract class TRxMsg { public byte typeMsg; } public class TRxMsgAcceptMask:TRxMsg { public uint accept, mask; //... } public class TRxMsgSN:TRxMsg { public string SN; //... } public class TRxMsgMRate:TRxMsg { public ushort rx_rate, tx_rate; //... } public class TRxMsgStatus:TRxMsg { public byte rx_status, tx_status, ctl0, ctl1, rflg; //... } Finally I create the appropriate object and initialize it with values manually converted from "myMsg" array (I used BitConverter for this). This does work fine, this solution seems to me a little too complicated, and that it should be possible to do this somehow more directly, without the auxiliary "my9bytes" structures or the inheritance and manual converting of individual values. So I'd like to ask you for a suggestions for the best way to do this. Thanks a lot!

    Read the article

  • UI Design Choices and How to Implement Them

    - by AKRamkumar
    I am making an application that is a dashboard/widget host. I am using MEF to load the plugins and I have a ui Concept Idea like this: http://i42.tinypic.com/scb6nd.png Is this a good design choice? How would I implement the Navigation? Is there any Design Patter you would reccomend for this? Note: My contract interface is this. public interface IDashboardPlugin { public string Name{get;} public string Description{get;} public string Author{get;} public UIElement UI{get;} }

    Read the article

  • iPhone memory management

    - by Prazi
    I am newbie to iPhone programming. I am not using Interface Builder in my programming. I have some doubt about memory management, @property topics in iPhone. Consider the following code @interface LoadFlag : UIViewController { UIImage *flag; UIImageView *preview; } @property (nonatomic, retain) UIImageView *preview; @property (nonatomic, retain) UIImage *flag; @implementation @synthesize preview; @synthesize flag; - (void)viewDidLoad { flag = [UIImage imageNamed:@"myImage.png"]]; NSLog(@"Preview: %d\n",[preview retainCount]); //Count: 0 but shouldn't it be 1 as I am retaining it in @property in interface file preview=[[UIImageView alloc]init]; NSLog(@"Count: %d\n",[preview retainCount]); //Count: 1 preview.frame=CGRectMake(0.0f, 0.0f, 100.0f, 100.0f); preview.image = flag; [self.view addSubview:preview]; NSLog(@"Count: %d\n",[preview retainCount]); //Count: 2 [preview release]; NSLog(@"Count: %d\n",[preview retainCount]); //Count: 1 } When & Why(what is the need) do I have to set @property with retain (in above case for UIImage & UIImageView) ? I saw this statement in many sample programs but didn't understood the need of it. When I declare @property (nonatomic, retain) UIImageView *preview; statement the retain Count is 0. Why doesn't it increase by 1 inspite of retaining it in @property. Also when I declare [self.view addSubview:preview]; then retain Count increments by 1 again. In this case does the "Autorelease pool" releases for us later or we have to take care of releasing it. I am not sure but I think that the Autorelease should handle it as we didn't explicitly retained it so why should we worry of releasing it. Now, after the [preview release]; statement my count is 1. Now I don't need UIImageView anymore in my program so when and where should I release it so that the count becomes 0 and the memory gets deallocated. Again, I am not sure but I think that the Autorelease should handle it as we didn't explicitly retained it so why should we worry of releasing it. What will happen if I release it in -(void) dealloc method In the statement - flag = [UIImage imageNamed:@"myImage.png"]]; I haven't allocated any memory to flag but how can I still use it in my program. In this case if I do not allocate memory then who allocates & deallocates memory to it or is the "flag" just a reference pointing to - [UIImage imageNamed:@"myImage.png"]];. If it is a reference only then do i need to release it. Thanks in advance.

    Read the article

  • Prepopulate drop-box according to another drop-box choice in Django Admin

    - by onorua
    I have models like this: class User(models.Model): Switch = models.ForeignKey(Switch, related_name='SwitchUsers') Port = models.ForeignKey(Port) class Switch(models.Model): Name = models.CharField(max_length=50) class Port(models.Model): PortNum = models.PositiveIntegerField() Switch = models.ForeignKey(Switch, related_name = "Ports") When I'm in Admin interface and choose Switch from Switches available, I would like to have Port prepopulated accordingly with Ports from the related Switch. As far as I understand I need to create some JS script to prepopulate it. Unfortunately I don't have this experience, and I would like to keep things simple as it possible and don't rewrite all Django admin interface. Just add this functionality for one Field. Could you please help me with my problem? Thank you.

    Read the article

  • What is the best way to interoperably serialize a message?

    - by iwein
    I'm considering message serialization support for spring-integration. This would be useful for various wire level transports to implement guaranteed delivery, but also to allow interoperability with other messaging systems (e.g. through AMQP). The fundamental problem that arises is that a message containing Java object in it's payload and headers should be converted to a byte[] and/or written to a stream. Java's own serialization is clearly not going to cut it because that is not interoperable. My preference would be to create an interface that allows the user to implement the needed logic for all Objects that take part in serialization. Is this a sensible idea and what would the interface look like? Is there a standard interoperable way to serialize Objects that would make sense in this context?

    Read the article

  • Testing Java Classes with JMeter

    - by Martin Dürrmeier
    I'd like to test a Java Service Call. My first attempt was to use the "Java Request Sampler" The docu says This sampler lets you control a java class that implements the JavaSamplerClient interface. I'm not sure how to get the org.apache.jmeter.protocol.java.sampler.JavaSamplerClient Interface as there is no Maven Artifact nor provided binaries on the JMeter side. Just a JMeter Maven Plugin (which is not what I'm looking for). I could install the needed binaries in my local Maven Repository, I Just don't know where they are available. Wondering if anybody at all is using the "Java Request Sampler" ? P.S. Maybe I should try the JUnit Sampler

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 197 198 199 200 201 202 203 204 205 206 207 208  | Next Page >