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  • What language has the longest "Hello world" program?

    - by Kip
    In most scripting languages, a "Hello world!" application is very short: print "Hello world" In C++, it is a little more complicated, requiring at least 46 non-whitespace characters: #include <cstdio> int main() { puts("Hello world"); } Java, at 75 non-whitespace characters, is even more verbose: class A { public static void main(String[] args) { System.out.print("Hello world"); } } Are there any languages that require even more non-whitespace characters than Java? Which language requires the most? Notes: I'm asking about the length of the shortest possible "hello world" application in a given language. A newline after "Hello world" is not required. I'm not counting whitespace, but I know there is some language that uses only whitespace characters. If you use that one you can count the whitespace characters.

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  • Suggest me solution to track the change in test DB and replicate in Another DB

    - by Parth
    Suggest me solution to track the change in test DB and replicate in Another DB... My Client need a script or any solution, if he has two Database, One Test DB in which he tests his data on test portal and if he find it appropriate he can use those changes to be done in main DB to display on Live site.. Fior this he needs the solution to record or track all updation/deletion/insertion, so that he can do the same in main DB if found appropriate, ** NOTE: ** we hav only on server, no separate server, hence binary log replication doesnt seems to be working for my case...

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  • Technical/Programming/Non-SEO Pros and Cons of WWW or no-WWW?

    - by Ingenutrix
    What are technical/programming/non-SEO pros and cons of www or no-www, for domains as well as sub-domains? From Jeff Atwood's twitter at http://twitter.com/codinghorror/status/1637428313 : "sort of regretting the no-www choice because it causes full cookie submission to ALL subdomains. :(" What does this mean? Is there a blog post or article detailing this? What other specific issues and their reasons should be considered for www. vs no-www. Update: On searching for more info on this topic, I found following helpful ( in addition to Laurence Gonsalves answer ) : Dropping the WWW Prefix Impact on search results: Jivlain's and Isaac Lin's comments Use Cookie-free Domains for Components on StackOverflow : Should I default my website to www.foo or not? on StackOverflow : When should one use a ‘www’ subdomain?

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  • Help with starting up my thin server with Sinatra

    - by enedi
    Hi All, I'm a newcomer trying to get my feet wet with Ruby and Sinatra. I followed the Slicehost articles in getting Ruby 1.9.1 setup along with Thin 1.2.7 with a reverse proxy to Nginx. Most things were going pretty smooth until I tried to start up my thin server. This is the output I get from my logs: $ sudo thin -C config.yml -R config.ru start /home/user/public_html/testapp/config.ru:9:in `block in <main>': undefined method `application' for Sinatra:Module (NoMethodError) from /var/lib/gems/1.9.1/gems/rack-1.1.0/lib/rack/builder.rb:46:in `instance_eval' from /var/lib/gems/1.9.1/gems/rack-1.1.0/lib/rack/builder.rb:46:in `initialize' from /home/user/public_html/testapp/config.ru:1:in `new' from /home/user/public_html/testapp/config.ru:1:in `<main>' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/rack/adapter/loader.rb:36:in `eval' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/rack/adapter/loader.rb:36:in `load' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/thin/controllers/controller.rb:175:in `load_rackup_config' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/thin/controllers/controller.rb:65:in `start' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/thin/runner.rb:177:in `run_command' from /var/lib/gems/1.9.1/gems/thin-1.2.7/lib/thin/runner.rb:143:in `run!' from /var/lib/gems/1.9.1/gems/thin-1.2.7/bin/thin:6:in `<top (required)>' from /usr/bin/thin:19:in `load' from /usr/bin/thin:19:in `<main>' I can post my config.yml, config.ru and myapp.rb, where my Sinatra code resides (it's basically the sample code ripped from the top of the Sinatra book), if anyone needs to see it, but if you have any ideas on what's going on based on that log itself, I'd appreciate it, as I couldn't find anything on the world wide Google. Also, is this still the preferred way of running Sinatra on thin? I can get the app working with just running it through Ruby itself: $ ruby myapp.rb == Sinatra/1.0 has taken the stage on 4567 for development with backup from Thin This allows me to see my pages in my sandbox. Thank you, all.

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  • Base64 Encode String in VBScript

    - by Patrick Cuff
    I have a web service load driver that's a Windows Script File (WSF), that includes some VBScript and JavaScript files. My web service requires that the incoming message is base64 encoded. I currently have a VBScript function that does this, but it's very inefficient (memory intensive, mostly due to VBScripts awful string concatenation) [Aside; Yes, I've seen Jeff's latest blog post. The concatenation is happening in a loop across messages that are 1,000's to 10,000's bytes in size.] I've tried using some custom string concatenation routines; one using an array and one using ADODB.Stream. These help, a little, but I think it would help more if I had some other way of encoding the message rather than via my own VBS function. Is there some other way of encoding my message, preferebly using native Windows methods?

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  • How to paint fully transparent pixels/points in P2D mode?

    - by netzwerg
    According to the Processing Reference, stroke(gray, alpha) allows to set the color and opacity of the stroke. With the default color mode, an alpha value of 255 denotes full opacity, while a value of 0 should correspond to complete transparency. While this works with the (default) JAVA2D renderer, I can't seem to paint fully transparent points in P2D mode. This code clearly renders a pixel at the center of the canvas, even though the alpha value is set to 0 (fully transparent): public class Transparency extends PApplet { @Override public void setup() { size(200, 200, P2D); } @Override public void draw() { stroke(0, 0); point(width / 2, height / 2); } public static void main(String[] args) { PApplet.main(new String[] { Transparency.class.getSimpleName() }); } } What's wrong here?

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  • Help organising controllers logically

    - by kenny99
    Hi guys, I'm working on a site which i'm developing using an MVC structure. My models will represent all of data in the site, but i'm struggling a bit to decide on a good controller structure. The site will allow users to login/register and see personal data on a number of pages, but also still have access to public pages, e.g FAQs, Contact page etc. This is what I have at the moment... A Template Controller which handles main template display. The basic template for the site will remain the same whether or not you are logged in. A main Website Controller which extends the Template Controller and handles basic authentication. If the user is logged in, a User::control_panel() method is called from the constructor and this builds the control panel which will be present throughout the authenticated session. If user is not logged in, then a different view is loaded instead of the control panel, e.g with a login form. All protected/public page related controllers will extend the website controller. The user homepage has a number of widgets I want to display, which I'm doing via a Home Controller which extends the Website Controller. This controller generates these widgets via the following static calls: $this->template->content->featured_pet = Pet::featured(); $this->template->content->popular_names = Pet::most_popular(); $this->template->content->owner_map = User::generate_map(); $this->template->content->news = News::snippet(); I suppose the first thing I'm unsure about is if the above static calls to controllers (e.g Pet and User) are ok to remain static - these static methods will return views which are loaded into the main template. This is the way I've done things in the past but I'm curious to find out if this is a sensible approach. Other protected pages for signed in users will be similar to the Home Controller. Static pages will be handled by a Page Controller which will also extend the Website Controller, so that it will know whether or not the user control panel or login form should be shown on the left hand side of the template. The protected member only pages will not be routed to the Page Controller, this controller will only handle publicly available pages. One problem I have at the moment, is that if both public and protected pages extend the Website Controller, how do I avoid an infinite loop - for example, the idea is that the website controller should handle authentication then redirect to the requested controller (URL), but this will cause an infinite redirect loop, so i need to come up with a better way of dealing with this. All in all, does this setup make any sense?! Grateful for any feedback.

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  • What does the C compiler error "looks like a function definition, but there is no parameter list;" m

    - by user312309
    #include <iostream> #include <fstream> using namespace std; int main { int num1, num2; ifstream infile; ostream outfile; infile.open("input.dat"); outfile.open("output.dat"); infile >> num 1 >> num 2; outfile << "Sum = " << num1 + num2 << endl; infile.close() outfile.close() return 0; } this is what i did and when i compile it, i got this error that said error C2470: 'main' : looks like a function definition, but there is no parameter list; skipping apperent body please dont hate me :( i am new at this computer science....

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  • How to parse deeply nested using LINQ to XML

    - by Picflight
    How do I parse the following XML using LINQ? I need to insert into a database table OrderNumber, ShipAddress, ShipCity, ShipState for each Order & OrderCancelled. Then in a separate table I need to insert OrderId from the Returns/Amount section. <!-- language: lang-xml --> <?xml version="1.0" encoding="utf-8"?> <OrdersReport Date="2012-08-01"> <Client> <ClientId>1</ClientId> <Orders> <Order> <OrderNumber>1</OrderNumber> <ShipAddress>123 Main St.</ShipAddress> <ShipCity>MyCity</ShipCity> <ShipState>AZ</ShipState> </Order> <Order> <OrderNumber>2</OrderNumber> <ShipAddress>111 Main St.</ShipAddress> <ShipCity>OtherCity</ShipCity> <ShipState>AL</ShipState> </Order> <OrderCancelled> <OrderNumber>3</OrderNumber> <ShipAddress>111 Main St.</ShipAddress> <ShipCity>OtherCity</ShipCity> <ShipState>AL</ShipState> </OrderCancelled> </Orders> <Returns> <Amount> <OrderId>2</OrderId> <OrderId>3</OrderId> </Amount> </Returns> </Client> <Client> <ClientId>2</ClientId> <!-- Same Tree structure as Client 1 --> </Client> </OrdersReport> Not sure why the XML is not showing red and blue colors and not indenting properly. :-(

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  • unable to connect to Mailchimp services using java wrapper

    - by Nagesh
    I am using Java wrapper of mailchimp API for converting to inline CSS. I downloaded the java wrapper and tried with method inlineCss(); I register with Mailchimp and got the Api key. API Key: d5296efe2d4879e90d95b151804f8d30-us1 I am getting the below exception while calling the ping(apiKey) method. Could you please provide me the solution to resolve this problem. Exception in thread "main" com.nwire.mailchimp.MailChimpServiceException: Failed to read servers response: api.mailchimp.com at com.nwire.mailchimp.MailChimpServiceFactory$ClientFactory$1.invoke(MailChimpServiceFactory.java:190) at $Proxy0.ping(Unknown Source) at com.nwire.mailchimp.test.InlineTest.initialize(InlineTest.java:44) at com.nwire.mailchimp.test.InlineTest.run(InlineTest.java:36) at com.nwire.mailchimp.test.InlineTest.main(InlineTest.java:23) Below is the code I am using for connecting to Mailchimp. public void initialize() { mcServices = MailChimpServiceFactory.getMailChimpServices(); final String ping = mcServices.ping(apiKey); if (IMailChimpServices.PING_SUCCESS.equals(ping)) { logger.error("MailChimp connection pinged successfully"); } else { logger.error("Failed to ping MailChimp, response: " + ping); } } Regards, Nagesh.

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  • Android Window Mananger leacked windwo progress dialog

    - by saravanan-palpandi
    05-14 16:53:52.273: ERROR/WindowManager(412): Activity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@43db2e68 that was originally added here 05-14 16:53:52.273: ERROR/WindowManager(412): android.view.WindowLeaked: Activity com.sss.client.AddClient has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@43db2e68 that was originally added here 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewRoot.(ViewRoot.java:227) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:148) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.Window$LocalWindowManager.addView(Window.java:424) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.Dialog.show(Dialog.java:239) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.ProgressDialog.show(ProgressDialog.java:107) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.ProgressDialog.show(ProgressDialog.java:90) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.ProgressDialog.show(ProgressDialog.java:85) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.sss.client.AddClient.searchValues(AddClient.java:236) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.sss.client.AddClient.clientFormAction(AddClient.java:264) 05-14 16:53:52.273: ERROR/WindowManager(412): at java.lang.reflect.Method.invokeNative(Native Method) 05-14 16:53:52.273: ERROR/WindowManager(412): at java.lang.reflect.Method.invoke(Method.java:521) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.View$1.onClick(View.java:2026) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.View.performClick(View.java:2364) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.View.onTouchEvent(View.java:4179) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.widget.TextView.onTouchEvent(TextView.java:6540) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.View.dispatchTouchEvent(View.java:3709) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.Activity.dispatchTouchEvent(Activity.java:2061) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.view.ViewRoot.handleMessage(ViewRoot.java:1691) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.os.Handler.dispatchMessage(Handler.java:99) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.os.Looper.loop(Looper.java:123) 05-14 16:53:52.273: ERROR/WindowManager(412): at android.app.ActivityThread.main(ActivityThread.java:4363) 05-14 16:53:52.273: ERROR/WindowManager(412): at java.lang.reflect.Method.invokeNative(Native Method) 05-14 16:53:52.273: ERROR/WindowManager(412): at java.lang.reflect.Method.invoke(Method.java:521) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860) 05-14 16:53:52.273: ERROR/WindowManager(412): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618) 05-14 16:53:52.273: ERROR/WindowManager(412): at dalvik.system.NativeStart.main(Native Method) when show the dialog box it show the error message please do reply me

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  • Throwing an exception from a BackgroundWorker which calls an async. method (Webrequest)

    - by mrbamboo
    Hi, My main application creates a new BackgroundWorker X the DoWork event handler of X calls a method Y of my controller. This method creates the WebRequest (async.) instance and the callback using AsyncCallback. When the response arrives the callback method Z gets called and the content will be analyzed. It can happen that the response has an unwanted content. At that moment callback Z will throw an exception. I want to catch this exception in my main application. I tried it in DoWork and RunWorkerCompleted but nothing can be caught from there. Error in RunWorkerCompletedEventArgs is always null.

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  • problem with two .NET threads and hardware access

    - by mack369
    I'm creating an application which communicates with the device via FT2232H USB/RS232 converter. For communication I'm using FTD2XX_NET.dll library from FTDI website. I'm using two threads: first thread continuously reads data from the device the second thread is the main thread of the Windows Form Application I've got a problem when I'm trying to write any data to the device while the receiver's thread is running. The main thread simply hangs up on ftdiDevice.Write function. I tried to synchronize both threads so that only one thread can use Read/Write function at the same time, but it didn't help. Below code responsible for the communication. Note that following functions are methods of FtdiPort class. Receiver's thread private void receiverLoop() { if (this.DataReceivedHandler == null) { throw new BackendException("dataReceived delegate is not set"); } FTDI.FT_STATUS ftStatus = FTDI.FT_STATUS.FT_OK; byte[] readBytes = new byte[this.ReadBufferSize]; while (true) { lock (FtdiPort.threadLocker) { UInt32 numBytesRead = 0; ftStatus = ftdiDevice.Read(readBytes, this.ReadBufferSize, ref numBytesRead); if (ftStatus == FTDI.FT_STATUS.FT_OK) { this.DataReceivedHandler(readBytes, numBytesRead); } else { Trace.WriteLine(String.Format("Couldn't read data from ftdi: status {0}", ftStatus)); Thread.Sleep(10); } } Thread.Sleep(this.RXThreadDelay); } } Write function called from main thread public void Write(byte[] data, int length) { if (this.IsOpened) { uint i = 0; lock (FtdiPort.threadLocker) { this.ftdiDevice.Write(data, length, ref i); } Thread.Sleep(1); if (i != (int)length) { throw new BackendException("Couldnt send all data"); } } else { throw new BackendException("Port is closed"); } } Object used to synchronize two threads static Object threadLocker = new Object(); Method that starts the receiver's thread private void startReceiver() { if (this.DataReceivedHandler == null) { return; } if (this.IsOpened == false) { throw new BackendException("Trying to start listening for raw data while disconnected"); } this.receiverThread = new Thread(this.receiverLoop); //this.receiverThread.Name = "protocolListener"; this.receiverThread.IsBackground = true; this.receiverThread.Start(); } The ftdiDevice.Write function doesn't hang up if I comment following line: ftStatus = ftdiDevice.Read(readBytes, this.ReadBufferSize, ref numBytesRead);

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  • How to work with varargs and reflection

    - by PeterMmm
    Simple question, how make this code working ? public class T { public static void main(String[] args) throws Exception { new T().m(); } public // as mentioned by Bozho void foo(String... s) { System.err.println(s[0]); } void m() throws Exception { String[] a = new String[]{"hello", "kitty"}; System.err.println(a.getClass()); Method m = getClass().getMethod("foo", a.getClass()); m.invoke(this, (Object[]) a); } } Output: class [Ljava.lang.String; Exception in thread "main" java.lang.IllegalArgumentException: wrong number of arguments at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597)

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  • Why is my masm32 program crashing whenever I try using interrupts?

    - by incrediman
    Here's the code: .386 ;target for maximum compatibility .model small,stdcall ;model .code main: int 20h END main Result: http://img705.imageshack.us/img705/3738/resultom.png "test.exe has stopped working" - always right when it reaches the interrupt. This is the interrupt I'm trying to use. It should simply exit the program. Others I've tried include character input/output, etc.. Nothing works. I'm on windows 7, using masm32 with the WinAsm IDE. There are so many cool things it seems I should be able to do with interrupts... however, it crashes whenever I try to use an interrupt - always the same way. This seems related and possibly useful: http://stackoverflow.com/questions/1414260/dos-interrupt-in-masm-x86-assembly-crashing ...but I haven't really been able to figure anything out from it. Any suggestions?

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  • NSOperation and UIKit problem

    - by Infinity
    Hello guys! I am doing my download with an object which was inherited from NSOperation. I have read the documentation and when my operation finished I must call the [self.delegate performSelectorOnMainThread:@selector(operationDidFinish:) withObject:self waitUntilDone:YES]; method. It needs to be called on the main thread, because the UIKit is not thread safe and the documentation says this in these non thread safe frameworks cases. In the delegate method I am drawing a pdf or an image, but because it is drawn on the main thread the User Interface is very laggy until the drawing is finished. Maybe can you suggest me a good way to avoid this problem?

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  • Cheetah pre-compiled template usage quesion

    - by leo
    For performance reason as suggested here, I am studying how to used the pr-compiled template. I edit hello.tmpl in template directory as #attr title = "This is my Template" \${title} Hello \${who}! then issued cheetah-compile.exe .\hello.tmpl and get the hello.py In another python file runner.py , i have !/usr/bin/env python from Cheetah.Template import Template from template import hello def myMethod(): tmpl = hello.hello(searchList=[{'who' : 'world'}]) results = tmpl.respond() print tmpl if name == 'main': myMethod() But the outcome is ${title} Hello ${who}! Debugging for a while, i found that inside hello.py def respond(self, trans=None): ## CHEETAH: main method generated for this template if (not trans and not self._CHEETAH__isBuffering and not callable(self.transaction)): trans = self.transaction # is None unless self.awake() was called if not trans: trans = DummyTransaction() it looks like the trans is None, so it goes to DummyTransaction, what did I miss here? Any suggestions to how to fix it?

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  • Metaprograming - self explanatory code - tutorials, articles, books

    - by elena
    Hello everybody, I am looking into improving my programming skils (actually I try to do my best to suck less each year, as our Jeff Atwood put it), so I was thinking into reading stuff about metaprogramming and self explanatory code. I am looking for something like an idiot's guide to this (free books for download, online resources). Also I want more than your average wiki page and also something language agnostic or preferably with Java examples. Do you know of such resources that will allow to efficiently put all of it into prectice (I know experience has a lot to say in all of this but i kind of want to build experience avoiding the flow bad decitions - experience - good decitions)? Thank you!

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  • Core Data multi-threading

    - by JK
    My app starts by presenting a tableview whose datasource is a Core Data SQLite store. When the app starts, a secondary thread with its own store controller and context is created to obtain updates from the web for data in the store. However, any resulting changes to the store are not notified to the fetchedresults controller (I presume because it has its own coordinator) and consequently the table is not updated with store changes. What would be the most efficient way to refresh the context on the main thread? I am considering tracking the objectIDs of any objects changed on the secondary thread, sending those to the main thread when the secondary thread completes and invoking "[context refreshObject:....] Any help would be greatly appreciated.

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  • antlr3StringStreamNew string input error [ at offset 0, at <EOF> : cannot match to any predicted input... ]

    - by Embeguru
    I'm using ANTLR 3.4 with simplecTreeParser example and want to give string input from main.c I'v modified input in main as mentioned bellow pANTLR3_UINT8 input_string = (pANTLR3_UINT8)"int a;"; input = antlr3StringStreamNew(input_string, ANTLR3_ENC_8BIT, sizeof(input_string),(pANTLR3_UINT8)"ABCD"); Apparently getting following error -end of input-(1) : error 3 : 23:1: declaration : ( variable | functionHeader ';' - ^( FUNC_DECL functionHeader ) | functionHeader block - ^( FUNC_DEF functionHeader block ) );, at offset 0, at : cannot match to any predicted input... The parser returned 1 errors, tree walking aborted. Any other way to give String input Regards

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  • Calling python from Java?

    - by griffin
    I'm trying to call Jython from a Java 6 application using javax.script: import javax.script.ScriptEngine; import javax.script.ScriptEngineManager; import javax.script.ScriptException; public class jythonEx { public static void main (String args[]) throws ScriptException { ScriptEngineManager mgr = new ScriptEngineManager(); ScriptEngine pyEngine = mgr.getEngineByName("python"); try { pyEngine.eval("print \"Python - Hello, world!\""); } catch (Exception ex) { ex.printStackTrace(); } } } This is causing a NullPointerException: java.lang.NullPointerException at jythonEx.main(jythonEx.java:12) Does anyone have any idea what I'm doing wrong here?

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  • Blackjack game reshuffling problem-edited

    - by Jam
    I am trying to make a blackjack game where before each new round, the program checks to make sure that the deck has 7 cards per player. And if it doesn't, the deck clears, repopulates, and reshuffles. I have most of the problem down, but for some reason at the start of every deal it reshuffles the deck more than once, and I can't figure out why. Help, please. Here's what I have so far: (P.S. the imported cards and games modules aren't part of the problem, I'm fairly sure my problem lies in the deal() function of my BJ_Deck class.) import cards, games class BJ_Card(cards.Card): """ A Blackjack Card. """ ACE_VALUE = 1 def get_value(self): if self.is_face_up: value = BJ_Card.RANKS.index(self.rank) + 1 if value > 10: value = 10 else: value = None return value value = property(get_value) class BJ_Deck(cards.Deck): """ A Blackjack Deck. """ def populate(self): for suit in BJ_Card.SUITS: for rank in BJ_Card.RANKS: self.cards.append(BJ_Card(rank, suit)) def deal(self, hands, per_hand=1): for rounds in range(per_hand): if len(self.cards)>=7*(len(hands)): print "Reshuffling the deck." self.cards=[] self.populate() self.shuffle() for hand in hands: top_card=self.cards[0] self.give(top_card, hand) class BJ_Hand(cards.Hand): """ A Blackjack Hand. """ def __init__(self, name): super(BJ_Hand, self).__init__() self.name = name def __str__(self): rep = self.name + ":\t" + super(BJ_Hand, self).__str__() if self.total: rep += "(" + str(self.total) + ")" return rep def get_total(self): # if a card in the hand has value of None, then total is None for card in self.cards: if not card.value: return None # add up card values, treat each Ace as 1 total = 0 for card in self.cards: total += card.value # determine if hand contains an Ace contains_ace = False for card in self.cards: if card.value == BJ_Card.ACE_VALUE: contains_ace = True # if hand contains Ace and total is low enough, treat Ace as 11 if contains_ace and total <= 11: # add only 10 since we've already added 1 for the Ace total += 10 return total total = property(get_total) def is_busted(self): return self.total > 21 class BJ_Player(BJ_Hand): """ A Blackjack Player. """ def is_hitting(self): response = games.ask_yes_no("\n" + self.name + ", do you want a hit? (Y/N): ") return response == "y" def bust(self): print self.name, "busts." self.lose() def lose(self): print self.name, "loses." def win(self): print self.name, "wins." def push(self): print self.name, "pushes." class BJ_Dealer(BJ_Hand): """ A Blackjack Dealer. """ def is_hitting(self): return self.total < 17 def bust(self): print self.name, "busts." def flip_first_card(self): first_card = self.cards[0] first_card.flip() class BJ_Game(object): """ A Blackjack Game. """ def __init__(self, names): self.players = [] for name in names: player = BJ_Player(name) self.players.append(player) self.dealer = BJ_Dealer("Dealer") self.deck = BJ_Deck() self.deck.populate() self.deck.shuffle() def get_still_playing(self): remaining = [] for player in self.players: if not player.is_busted(): remaining.append(player) return remaining # list of players still playing (not busted) this round still_playing = property(get_still_playing) def __additional_cards(self, player): while not player.is_busted() and player.is_hitting(): self.deck.deal([player]) print player if player.is_busted(): player.bust() def play(self): # deal initial 2 cards to everyone self.deck.deal(self.players + [self.dealer], per_hand = 2) self.dealer.flip_first_card() # hide dealer's first card for player in self.players: print player print self.dealer # deal additional cards to players for player in self.players: self.__additional_cards(player) self.dealer.flip_first_card() # reveal dealer's first if not self.still_playing: # since all players have busted, just show the dealer's hand print self.dealer else: # deal additional cards to dealer print self.dealer self.__additional_cards(self.dealer) if self.dealer.is_busted(): # everyone still playing wins for player in self.still_playing: player.win() else: # compare each player still playing to dealer for player in self.still_playing: if player.total > self.dealer.total: player.win() elif player.total < self.dealer.total: player.lose() else: player.push() # remove everyone's cards for player in self.players: player.clear() self.dealer.clear() def main(): print "\t\tWelcome to Blackjack!\n" names = [] number = games.ask_number("How many players? (1 - 7): ", low = 1, high = 8) for i in range(number): name = raw_input("Enter player name: ") names.append(name) print game = BJ_Game(names) again = None while again != "n": game.play() again = games.ask_yes_no("\nDo you want to play again?: ") main() raw_input("\n\nPress the enter key to exit.") Since someone decided to call this 'psychic-debugging', I'll go ahead and tell you what the modules are then. Here's the cards module: class Card(object): """ A playing card. """ RANKS = ["A", "2", "3", "4", "5", "6", "7", "8", "9", "10", "J", "Q", "K"] SUITS = ["c", "d", "h", "s"] def __init__(self, rank, suit, face_up = True): self.rank = rank self.suit = suit self.is_face_up = face_up def __str__(self): if self.is_face_up: rep = self.rank + self.suit else: rep = "XX" return rep def flip(self): self.is_face_up = not self.is_face_up class Hand(object): """ A hand of playing cards. """ def init(self): self.cards = [] def __str__(self): if self.cards: rep = "" for card in self.cards: rep += str(card) + "\t" else: rep = "<empty>" return rep def clear(self): self.cards = [] def add(self, card): self.cards.append(card) def give(self, card, other_hand): self.cards.remove(card) other_hand.add(card) class Deck(Hand): """ A deck of playing cards. """ def populate(self): for suit in Card.SUITS: for rank in Card.RANKS: self.add(Card(rank, suit)) def shuffle(self): import random random.shuffle(self.cards) def deal(self, hands, per_hand = 1): for rounds in range(per_hand): for hand in hands: if self.cards: top_card = self.cards[0] self.give(top_card, hand) else: print "Can't continue deal. Out of cards!" if name == "main": print "This is a module with classes for playing cards." raw_input("\n\nPress the enter key to exit.") And here's the games module: class Player(object): """ A player for a game. """ def __init__(self, name, score = 0): self.name = name self.score = score def __str__(self): rep = self.name + ":\t" + str(self.score) return rep def ask_yes_no(question): """Ask a yes or no question.""" response = None while response not in ("y", "n"): response = raw_input(question).lower() return response def ask_number(question, low, high): """Ask for a number within a range.""" response = None while response not in range(low, high): response = int(raw_input(question)) return response if name == "main": print "You ran this module directly (and did not 'import' it)." raw_input("\n\nPress the enter key to exit.")

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  • Query on simple C++ threadpool implementation

    - by ticketman
    Stackoverflow has been a tremendous help to me and I'd to give something back to the community. I have been implementing a simple threadpool using the tinythread C++ portable thread library, using what I have learnt from Stackoverflow. I am new to thread programming, so not that comfortable with mutexes, etc. I have a question best asked after presenting the code (which runs quite well under Linux): // ThreadPool.h class ThreadPool { public: ThreadPool(); ~ThreadPool(); // Creates a pool of threads and gets them ready to be used void CreateThreads(int numOfThreads); // Assigns a job to a thread in the pool, but doesn't start the job // Each SubmitJob call will use up one thread of the pool. // This operation can only be undone by calling StartJobs and // then waiting for the jobs to complete. On completion, // new jobs may be submitted. void SubmitJob( void (*workFunc)(void *), void *workData ); // Begins execution of all the jobs in the pool. void StartJobs(); // Waits until all jobs have completed. // The wait will block the caller. // On completion, new jobs may be submitted. void WaitForJobsToComplete(); private: enum typeOfWorkEnum { e_work, e_quit }; class ThreadData { public: bool ready; // thread has been created and is ready for work bool haveWorkToDo; typeOfWorkEnum typeOfWork; // Pointer to the work function each thread has to call. void (*workFunc)(void *); // Pointer to work data void *workData; ThreadData() : ready(false), haveWorkToDo(false) { }; }; struct ThreadArgStruct { ThreadPool *threadPoolInstance; int threadId; }; // Data for each thread ThreadData *m_ThreadData; ThreadPool(ThreadPool const&); // copy ctor hidden ThreadPool& operator=(ThreadPool const&); // assign op. hidden // Static function that provides the function pointer that a thread can call // By including the ThreadPool instance in the void * parameter, // we can use it to access other data and methods in the ThreadPool instance. static void ThreadFuncWrapper(void *arg) { ThreadArgStruct *threadArg = static_cast<ThreadArgStruct *>(arg); threadArg->threadPoolInstance->ThreadFunc(threadArg->threadId); } // The function each thread calls void ThreadFunc( int threadId ); // Called by the thread pool destructor void DestroyThreadPool(); // Total number of threads available // (fixed on creation of thread pool) int m_numOfThreads; int m_NumOfThreadsDoingWork; int m_NumOfThreadsGivenJobs; // List of threads std::vector<tthread::thread *> m_ThreadList; // Condition variable to signal each thread has been created and executing tthread::mutex m_ThreadReady_mutex; tthread::condition_variable m_ThreadReady_condvar; // Condition variable to signal each thread to start work tthread::mutex m_WorkToDo_mutex; tthread::condition_variable m_WorkToDo_condvar; // Condition variable to signal the main thread that // all threads in the pool have completed their work tthread::mutex m_WorkCompleted_mutex; tthread::condition_variable m_WorkCompleted_condvar; }; cpp file: // // ThreadPool.cpp // #include "ThreadPool.h" // This is the thread function for each thread. // All threads remain in this function until // they are asked to quit, which only happens // when terminating the thread pool. void ThreadPool::ThreadFunc( int threadId ) { ThreadData *myThreadData = &m_ThreadData[threadId]; std::cout << "Hello world: Thread " << threadId << std::endl; // Signal that this thread is ready m_ThreadReady_mutex.lock(); myThreadData->ready = true; m_ThreadReady_condvar.notify_one(); // notify the main thread m_ThreadReady_mutex.unlock(); while(true) { //tthread::lock_guard<tthread::mutex> guard(m); m_WorkToDo_mutex.lock(); while(!myThreadData->haveWorkToDo) // check for work to do m_WorkToDo_condvar.wait(m_WorkToDo_mutex); // if no work, wait here myThreadData->haveWorkToDo = false; // need to do this before unlocking the mutex m_WorkToDo_mutex.unlock(); // Do the work switch(myThreadData->typeOfWork) { case e_work: std::cout << "Thread " << threadId << ": Woken with work to do\n"; // Do work myThreadData->workFunc(myThreadData->workData); std::cout << "#Thread " << threadId << ": Work is completed\n"; break; case e_quit: std::cout << "Thread " << threadId << ": Asked to quit\n"; return; // ends the thread } // Now to signal the main thread that my work is completed m_WorkCompleted_mutex.lock(); m_NumOfThreadsDoingWork--; // Unsure if this 'if' would make the program more efficient // if(NumOfThreadsDoingWork == 0) m_WorkCompleted_condvar.notify_one(); // notify the main thread m_WorkCompleted_mutex.unlock(); } } ThreadPool::ThreadPool() { m_numOfThreads = 0; m_NumOfThreadsDoingWork = 0; m_NumOfThreadsGivenJobs = 0; } ThreadPool::~ThreadPool() { if(m_numOfThreads) { DestroyThreadPool(); delete [] m_ThreadData; } } void ThreadPool::CreateThreads(int numOfThreads) { // Check a thread pool has already been created if(m_numOfThreads > 0) return; m_NumOfThreadsGivenJobs = 0; m_NumOfThreadsDoingWork = 0; m_numOfThreads = numOfThreads; m_ThreadData = new ThreadData[m_numOfThreads]; ThreadArgStruct threadArg; for(int i=0; i<m_numOfThreads; ++i) { threadArg.threadId = i; threadArg.threadPoolInstance = this; // Creates the thread and save in a list so we can destroy it later m_ThreadList.push_back( new tthread::thread( ThreadFuncWrapper, (void *)&threadArg ) ); // It takes a little time for a thread to get established. // Best wait until it gets established before creating the next thread. m_ThreadReady_mutex.lock(); while(!m_ThreadData[i].ready) // Check if thread is ready m_ThreadReady_condvar.wait(m_ThreadReady_mutex); // If not, wait here m_ThreadReady_mutex.unlock(); } } // Adds a job to the batch, but doesn't start the job void ThreadPool::SubmitJob(void (*workFunc)(void *), void *workData) { // Check that the thread pool has been created if(!m_numOfThreads) return; if(m_NumOfThreadsGivenJobs >= m_numOfThreads) return; m_ThreadData[m_NumOfThreadsGivenJobs].workFunc = workFunc; m_ThreadData[m_NumOfThreadsGivenJobs].workData = workData; std::cout << "Submitted job " << m_NumOfThreadsGivenJobs << std::endl; m_NumOfThreadsGivenJobs++; } void ThreadPool::StartJobs() { // Check that the thread pool has been created // and some jobs have been assigned if(!m_numOfThreads || !m_NumOfThreadsGivenJobs) return; // Set 'haveworkToDo' flag for all threads m_WorkToDo_mutex.lock(); for(int i=0; i<m_NumOfThreadsGivenJobs; ++i) m_ThreadData[i].haveWorkToDo = true; m_NumOfThreadsDoingWork = m_NumOfThreadsGivenJobs; // Reset this counter so we can resubmit jobs later m_NumOfThreadsGivenJobs = 0; // Notify all threads they have work to do m_WorkToDo_condvar.notify_all(); m_WorkToDo_mutex.unlock(); } void ThreadPool::WaitForJobsToComplete() { // Check that a thread pool has been created if(!m_numOfThreads) return; m_WorkCompleted_mutex.lock(); while(m_NumOfThreadsDoingWork > 0) // Check if all threads have completed their work m_WorkCompleted_condvar.wait(m_WorkCompleted_mutex); // If not, wait here m_WorkCompleted_mutex.unlock(); } void ThreadPool::DestroyThreadPool() { std::cout << "Ask threads to quit\n"; m_WorkToDo_mutex.lock(); for(int i=0; i<m_numOfThreads; ++i) { m_ThreadData[i].haveWorkToDo = true; m_ThreadData[i].typeOfWork = e_quit; } m_WorkToDo_condvar.notify_all(); m_WorkToDo_mutex.unlock(); // As each thread terminates, catch them here for(int i=0; i<m_numOfThreads; ++i) { tthread::thread *t = m_ThreadList[i]; // Wait for thread to complete t->join(); } m_numOfThreads = 0; } Example of usage: (this calculates pi-squared/6) struct CalculationDataStruct { int inputVal; double outputVal; }; void LongCalculation( void *theSums ) { CalculationDataStruct *sums = (CalculationDataStruct *)theSums; int terms = sums->inputVal; double sum; for(int i=1; i<terms; i++) sum += 1.0/( double(i)*double(i) ); sums->outputVal = sum; } int main(int argc, char** argv) { int numThreads = 10; // Create pool ThreadPool threadPool; threadPool.CreateThreads(numThreads); // Create thread workspace CalculationDataStruct sums[numThreads]; // Set up jobs for(int i=0; i<numThreads; i++) { sums[i].inputVal = 3000*(i+1); threadPool.SubmitJob(LongCalculation, &sums[i]); } // Run the jobs threadPool.StartJobs(); threadPool.WaitForJobsToComplete(); // Print results for(int i=0; i<numThreads; i++) std::cout << "Sum of " << sums[i].inputVal << " terms is " << sums[i].outputVal << std::endl; return 0; } Question: In the ThreadPool::ThreadFunc method, would better performance be obtained if the following if statement if(NumOfThreadsDoingWork == 0) was included? Also, I'd be grateful of criticisms and ways to improve the code. At the same time, I hope the code is of use to others.

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  • Android app in eclipse

    - by Colin
    Hello everybody, i've searched for days but cant find an answer, perhaps you guys can help. I'm creating an android app in eclipse, it all works just one thing is bugging me. this is my main.java: package com.test; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Toast; public class Main extends Activity implements OnClickListener { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // Add Click listeners for all buttons View firstButton = findViewById(R.id.btn_rassen); firstButton.setOnClickListener(this); View secondButton = findViewById(R.id.button2); secondButton.setOnClickListener(this); } // Process the button click events @Override public void onClick(View v) { switch(v.getId()){ case R.id.btn_rassen: Intent j = new Intent(this, Webscreen.class); j.putExtra(com.test.Webscreen.URL, "http://www.google.com/"); startActivity(j); break; case R.id.button2: Intent k = new Intent(this, Webscreen.class); k.putExtra(com.test.Webscreen.URL, "http://notworkingurltotest.com"); startActivity(k); break; } } } now when it calls the webview.java the page called shows up but not the buttons i created in the layout xml page. does anybody have any idea why this is? your help is much appreciated! ohw this is my webscreen.java package com.test; import android.app.Activity; import android.app.AlertDialog; import android.app.ProgressDialog; import android.content.DialogInterface; import android.content.Intent; import android.net.Uri; import android.os.Bundle; import android.util.Log; import android.view.Window; import android.webkit.WebSettings; import android.webkit.WebView; import android.webkit.WebViewClient; import android.widget.Toast; public class Webscreen extends Activity { public static final String URL = ""; private static final String TAG = "WebscreenClass"; private WebView webview; private ProgressDialog progressDialog; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.webscreen); this.getIntent().getExtras(); this.webview = (WebView) findViewById(R.string.webview); String turl = getIntent().getStringExtra(URL); Log.i(TAG, " URL = "+turl); WebView webview = new WebView(this); setContentView(webview); final Activity activity = this; webview.setWebViewClient(new WebViewClient() { public boolean shouldOverrideUrlLoading(WebView view, String url) { view.loadUrl(url); return true; } public void onLoadResource (WebView view, String url) { if (progressDialog == null) { progressDialog = new ProgressDialog(activity); progressDialog.setMessage("Bezig met laden..."); progressDialog.show(); } } public void onPageFinished(WebView view, String url) { if (progressDialog.isShowing()) { progressDialog.dismiss(); progressDialog = null; } } public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) { Intent myIntent = new Intent(); myIntent.setClassName("com.test", "com.test.Main"); startActivity(myIntent); Toast.makeText(activity, "Laden van onderdeel mislukt, probeer het later nog eens! ", Toast.LENGTH_LONG).show(); progressDialog.show(); } }); webview.loadUrl(turl); } } webscreen.xml layout: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="fill_parent"> <!-- <1> --> <LinearLayout android:orientation="horizontal" android:layout_width="fill_parent" android:layout_height="wrap_content"> <EditText android:id="@+id/url" android:layout_height="wrap_content" android:layout_width="wrap_content" android:lines="1" android:layout_weight="1.0" android:hint="http://" android:visibility="visible" /> <Button android:id="@+id/go_button" android:layout_height="wrap_content" android:layout_width="wrap_content" android:text="go_button" /> </LinearLayout> <!-- <2> --> <WebView android:id="@string/webview" android:layout_width="fill_parent" android:layout_height="0dip" /> </LinearLayout>

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