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  • How to use Scala in IntelliJ IDEA (or: why is it so difficult to get a working IDE for Scala)?

    - by Alex R
    I recently gave up trying to use Scala in Eclipse (basic stuff like completion doesn't work). So now I'm trying IntelliJ. I'm not getting very far. I've been able to edit programs (within syntax highlighting and completion... yay!). But I'm unable to run even the simplest "Hello World". This was the original error: Scala signature Predef has wrong version Expected 5.0 found: 4.1 in .... scala-library.jar But that was yesterday with IDEA 9.0.1. See below... UPDATE Today I uninstalled IntelliJ 9.0.1, and installed 9.0.2 Early Availability, with the 4/14 stable version of the Scala plug-in. Then I setup a project from scratch through the wizards: new project from scratch JDK is 1.6.u20 accept the default (project) instead of global / module accept the download of Scala 2.8.0beta1 into project's lib folder Created a new class: object hello { def main(args: Array[String]) { println("hello: " + args); } } For my efforts, I now have a brand-new error :) Here it is: Scalac internal error: class java.lang.ClassNotFoundException [java.net.URLClassLoader$1.run(URLClassLoader.java:202), java.security.AccessController.doPrivileged(Native Method), java.net.URLClassLoader.findClass(URLClassLoader.java:190), java.lang.ClassLoader.loadClass(ClassLoader.java:307), sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301), java.lang.ClassLoader.loadClass(ClassLoader.java:248), java.lang.Class.forName0(Native Method), java.lang.Class.forName(Class.java:169), org.jetbrains.plugins.scala.compiler.rt.ScalacRunner.main(ScalacRunner.java:72)] FINAL UPDATE I uninstalled 9.0.2 EA and reinstalled 9.0.1, but this time went with the 2.7.3 version of Scala rather than the default 2.7.6, because 2.7.3 is the one shown in the screen-shots at the IntelliJ website (I guess the screen-shots prove that they actually tested this version!). Now everything works!!!

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  • Porting a select loop application to Android with NDK. Design question.

    - by plaisthos
    Hi, I have an network application which uses a select loop like this: bool shutdown=false; while (!shutdown) { [do something] select(...,timeout); } THe main loop cannot work like this in an Android application anymore since the application needs to receive Intents, need to handle GUI, etc. I think I have basically three possibilities: Move the main loop to the java part of the application. Let the loop run in its own thread and somehow communicate from/to java. Screw Android <= 2.3 and use a native activity and use AInputQueue/ALooper instead of select. The first possibility is not easy since java has no select which works on fds. Simply using the select and return after each loop to java is not an elegant possibility either since that requires setting the timeout to something like 20ms to have a good response time in the java part of the program. The second probability sound nicer but I have do some communication between java and the c++/c part of the program. Things that cold work: Using a socket, kind of ugly. using native calls in the "java gui thread" and callback from native in the "c thread". Both threads need to have thread safe implementations but this is managable. I have not explored the third possibility but I think that it is not the way to go. I think I can hack something together which will work but I asking what is the best path to chose.

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  • How to generate a unique hash for a URL ?

    - by Jacques René Mesrine
    Given these two images from twitter. http://a3.twimg.com/profile_images/130500759/lowres_profilepic.jpg http://a1.twimg.com/profile_images/58079916/lowres_profilepic.jpg I want to download them to local filesystem & store them in a single directory. How shall I overcome name conflicts ? In the example above, I cannot store them as *lowres_profilepic.jpg*. My design idea is treat the URLs as opaque strings except for the last segment. What algorithms (implemented as f) can I use to hash the prefixes into unique strings. f( "http://a3.twimg.com/profile_images/130500759/" ) = 6tgjsdjfjdhgf f( "http://a1.twimg.com/profile_images/58079916/" ) = iuhd87ysdfhdk That way, I can save the files as:- 6tgjsdjfjdhgf_lowres_profilepic.jpg iuhd87ysdfhdk_lowres_profilepic.jpg I don't want a cryptographic algorithm as it this needs to be a performant operation.

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  • How to sketch out an event-driven system?

    - by Jordan
    I'm trying to design a system in Node.js (an attempt at solving one of my earlier problems, using Node's concurrency) but I'm running into trouble figuring out how to draw a plan of how the thing should operate. I'm getting very tripped up thinking in terms of callbacks instead of returned values. The flow isn't linear, and it's really boggling my ability to draft it. How does one draw out an operational flow for an event-driven system? I need something I can look at and say "Ok, yes, that's how it will work. I'll start it over here, and it will give me back these results over here." Pictures would be very helpful for this one. Thanks. Edit: I'm looking for something more granular than UML, specifically, something that will help me transition from a blocking and object-oriented programming structure, where I'm comfortable, to a non-blocking and event driven structure, where I'm unfamiliar.

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  • Designing Database

    - by user548192
    Hello All, I need to design database with frontend as HTML. This is my first attempt to do this. What I need is, - User can input a word from HTML page, click submit I will query the word to get a URL from database and user sees that webpage(pointed by URL). Just enter word, submit and get the webpage displayed. People suggested using JSP/Access. I am new to everything. Can you please point out what exactly I need to do? Thanks a ton.

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  • Main pricing and support for custom client pricing (Database Architecture ideas help - Rails)

    - by slythic
    Hi all, I have a personal project I'm planning and I came to a small hurdle. I want to have an item with price that will be the default for all clients/users. However, in my business I have some clients that are grandfathered in to some special pricing. In the case of these grandfathered in cases, I'll manually plug their special price in my admin section. Then all they will see is their special pricing while the regular users/clients see the default price. What is the best and simplest way to design the back-end for this? FYI - I'll be using rails as my framework. Many thanks! -Tony

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  • Navigate between screens in WPF

    - by Greg R
    This should be a very basic design question, but for some reason it doesn't seem to be well documented (maybe due to its simplicity?). If I'm building a dashboard application in WPF that brig up different CRM tasks and I want to navigate between screens, is this the best way to do this, or is there a better way? So for example I have Log In Screen - Main Menu Screen - Screen to one of different utilities var orderManagerWindow = new MyXamlView(); var loginWindow = Application.Current.MainWindow; orderManagerWindow.Left = loginWindow.Left; orderManagerWindow.Top = loginWindow.Top; Application.Current.MainWindow = orderManagerWindow; orderManagerWindow.Show(); loginWindow.Close(); I would really appreciate help and suggestions!

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  • Main pricing and support for individual client pricing (Database Architecture ideas help - Rails)

    - by slythic
    Hi all, I have a personal project I'm planning and I came to a small hurdle. I want to have an item with price that will be the default for all clients/users. However, in my business I have some clients that are grandfathered in to some special pricing. In the case of these grandfathered in cases, I'll manually plug their special price in my admin section. Then all they will see is their special pricing while the regular users/clients see the default price. What is the best and simplest way to design the back-end for this? FYI - I'll be using rails as my framework. Many thanks! -Tony

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  • Share application in local network

    - by hedgehogrider
    I would like to eventually create a managerial program that shares and updates information for multiple computers that are on the same network. I am fairly familiar with Python, C++ and a bit of Java, is there a library I could use with any of these languages to design such a program? I could probably create the local interface from where I am right now, but when it comes to packing and sharing data I could not be more clueless; any advice would be platinum. The program will need to differentiate between administrative and user access if that makes a difference.

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  • Web Sockets: Browser won't receive the message, complains about it not starting with 0x00 (byte)

    - by giggsey
    Here is my code: import java.net.*; import java.io.*; import java.util.*; import org.jibble.pircbot.*; public class WebSocket { public static int port = 12345; public static ArrayList<WebSocketClient> clients = new ArrayList<WebSocketClient>(); public static ArrayList<Boolean> handshakes = new ArrayList<Boolean>(); public static ArrayList<String> nicknames = new ArrayList<String>(); public static ArrayList<String> channels = new ArrayList<String>(); public static int indexNum; public static void main(String args[]) { try { ServerSocket ss = new ServerSocket(WebSocket.port); WebSocket.console("Created socket on port " + WebSocket.port); while (true) { Socket s = ss.accept(); WebSocket.console("New Client connecting..."); WebSocket.handshakes.add(WebSocket.indexNum,false); WebSocket.nicknames.add(WebSocket.indexNum,""); WebSocket.channels.add(WebSocket.indexNum,""); WebSocketClient p = new WebSocketClient(s,WebSocket.indexNum); Thread t = new Thread( p); WebSocket.clients.add(WebSocket.indexNum,p); indexNum++; t.start(); } } catch (Exception e) { WebSocket.console("ERROR - " + e.toString()); } } public static void console(String msg) { Date date = new Date(); System.out.println("[" + date.toString() + "] " + msg); } } class WebSocketClient implements Runnable { private Socket s; private int iAm; private String socket_res = ""; private String socket_host = ""; private String socket_origin = ""; protected String nick = ""; protected String ircChan = ""; WebSocketClient(Socket socket, int mynum) { s = socket; iAm = mynum; } public void run() { String client = s.getInetAddress().toString(); WebSocket.console("Connection from " + client); IRCclient irc = new IRCclient(iAm); Thread t = new Thread( irc ); try { Scanner in = new Scanner(s.getInputStream()); PrintWriter out = new PrintWriter(s.getOutputStream(),true); while (true) { if (! in.hasNextLine()) continue; String input = in.nextLine().trim(); if (input.isEmpty()) continue; // Lets work out what's wrong with our input if (input.length() > 3 && input.charAt(0) == 65533) { input = input.substring(2); } WebSocket.console("< " + input); // Lets work out if they authenticate... if (WebSocket.handshakes.get(iAm) == false) { checkForHandShake(input); continue; } // Lets check for NICK: if (input.length() > 6 && input.substring(0,6).equals("NICK: ")) { nick = input.substring(6); Random generator = new Random(); int rand = generator.nextInt(); WebSocket.console("I am known as " + nick); WebSocket.nicknames.set(iAm, "bo-" + nick + rand); } if (input.length() > 9 && input.substring(0,9).equals("CHANNEL: ")) { ircChan = "bo-" + input.substring(9); WebSocket.console("We will be joining " + ircChan); WebSocket.channels.set(iAm, ircChan); } if (! ircChan.isEmpty() && ! nick.isEmpty() && irc.started == false) { irc.chan = ircChan; irc.nick = WebSocket.nicknames.get(iAm); t.start(); continue; } else { irc.msg(input); } } } catch (Exception e) { WebSocket.console(e.toString()); e.printStackTrace(); } t.stop(); WebSocket.channels.remove(iAm); WebSocket.clients.remove(iAm); WebSocket.handshakes.remove(iAm); WebSocket.nicknames.remove(iAm); WebSocket.console("Closing connection from " + client); } private void checkForHandShake(String input) { // Check for HTML5 Socket getHeaders(input); if (! socket_res.isEmpty() && ! socket_host.isEmpty() && ! socket_origin.isEmpty()) { send("HTTP/1.1 101 Web Socket Protocol Handshake\r\n" + "Upgrade: WebSocket\r\n" + "Connection: Upgrade\r\n" + "WebSocket-Origin: " + socket_origin + "\r\n" + "WebSocket-Location: ws://" + socket_host + "/\r\n\r\n",false); WebSocket.handshakes.set(iAm,true); } return; } private void getHeaders(String input) { if (input.length() >= 8 && input.substring(0,8).equals("Origin: ")) { socket_origin = input.substring(8); return; } if (input.length() >= 6 && input.substring(0,6).equals("Host: ")) { socket_host = input.substring(6); return; } if (input.length() >= 7 && input.substring(0,7).equals("Cookie:")) { socket_res = "."; } /*input = input.substring(4); socket_res = input.substring(0,input.indexOf(" HTTP")); input = input.substring(input.indexOf("Host:") + 6); socket_host = input.substring(0,input.indexOf("\r\n")); input = input.substring(input.indexOf("Origin:") + 8); socket_origin = input.substring(0,input.indexOf("\r\n"));*/ return; } protected void send(String msg, boolean newline) { byte c0 = 0x00; byte c255 = (byte) 0xff; try { PrintWriter out = new PrintWriter(s.getOutputStream(),true); WebSocket.console("> " + msg); if (newline == true) msg = msg + "\n"; out.print(msg + c255); out.flush(); } catch (Exception e) { WebSocket.console(e.toString()); } } protected void send(String msg) { try { WebSocket.console(">> " + msg); byte[] message = msg.getBytes(); byte[] newmsg = new byte[message.length + 2]; newmsg[0] = (byte)0x00; for (int i = 1; i <= message.length; i++) { newmsg[i] = message[i - 1]; } newmsg[message.length + 1] = (byte)0xff; // This prints correctly..., apparently... System.out.println(Arrays.toString(newmsg)); OutputStream socketOutputStream = s.getOutputStream(); socketOutputStream.write(newmsg); } catch (Exception e) { WebSocket.console(e.toString()); } } protected void send(String msg, boolean one, boolean two) { try { WebSocket.console(">> " + msg); byte[] message = msg.getBytes(); byte[] newmsg = new byte[message.length+1]; for (int i = 0; i < message.length; i++) { newmsg[i] = message[i]; } newmsg[message.length] = (byte)0xff; // This prints correctly..., apparently... System.out.println(Arrays.toString(newmsg)); OutputStream socketOutputStream = s.getOutputStream(); socketOutputStream.write(newmsg); } catch (Exception e) { e.printStackTrace(); } } } class IRCclient implements Runnable { protected String nick; protected String chan; protected int iAm; boolean started = false; IRCUser irc; IRCclient(int me) { iAm = me; irc = new IRCUser(iAm); } public void run() { WebSocket.console("Connecting to IRC..."); started = true; irc.setNick(nick); irc.setVerbose(false); irc.connectToIRC(chan); } void msg(String input) { irc.sendMessage("#" + chan, input); } } class IRCUser extends PircBot { int iAm; IRCUser(int me) { iAm = me; } public void setNick(String nick) { this.setName(nick); } public void connectToIRC(String chan) { try { this.connect("irc.appliedirc.com"); this.joinChannel("#" + chan); } catch (Exception e) { WebSocket.console(e.toString()); } } public void onMessage(String channel, String sender,String login, String hostname, String message) { // Lets send this message to me WebSocket.clients.get(iAm).send(message); } } Whenever I try to send the message to the browser (via Web Sockets), it complains that it doesn't start with 0x00 (which is a byte). Any ideas? Edit 19/02 - Added the entire code. I know it's real messy and not neat, but I want to get it functioning first. Spend last two days trying to fix.

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  • Alternatives to Java for Android development?

    - by paul.meier
    Hey all, I've started developing Android apps a couple of months ago, and have a few under my belt. While I can tolerate Java enough to keep developing, I was wondering what success the community has had getting other languages to run. I've done some investigation as to how other JVM languages work, and it appears Dalvik messes them up pretty hard. Clojure seems unable to run, Scala seems to be one of the most successful. JRuby has also had some luck, but they caution against anything major. I've also checked out Scheme via Moby and Kawa, both of which seem to have some promise. What luck have any of you had? Languages I'm missing, misrepresenting? Any non-"Hello World" apps you've written in non-Java? Any snags in trying to get another language to run (e.g. "as long as you don't use continuations, you're fine in X Scheme"). Any particular snags in developing apps non-Java, once you get them to run? Thanks, hope you well ^_^

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  • JBoss Seam - Jetty - Virtualhosting

    - by Walter White
    Hi all, I am trying to cutback on the memory usage of my server and would like to optimize the architecture. I currently deploy 2 separate web applications to Jetty 6.1.22 that correspond to different virtualhosts. They have pretty much the same application stack except one has fewer components and are styled differently (content, images, css, etc.). If I change my design pattern over to EJB / EAR + 2 WARS embedded, will that lower the memory consumption? Will that give me a single instance of JBoss Seam, Quartz, and all of my components? They must use a different datasource. Thanks, Walter

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  • Jboss AS 7 - Dependency Injection

    - by Nic Willemse
    Im attempting to make use of dependency injection in Jboss AS 7 and im having huge difficulties. I have setup a EAR which contains both a EJB jar and a war. The war contains a richfaces web app. Im attempting to inject an EJB from the ejb jar into a faces managed bean with the code below : public class UserController { @EJB(mappedName="UserService") private UserFacadeService userService; public String getService(){ if(userService == null){ however when i deploy jboss puts the error in the console : rolled back with failure message {"Services with missing/unavailable dependencies" => ["jboss.deployment.subunit.\"GoodByeJohnEAR.ear\".\"GoodByeJohnWeb-1.0-SNAPSHOT.war\".component.\"managed-bean.za.co.gbj.UserController\".START missing [ jboss.naming.context.java.module.GoodByeJohnEAR.\"GoodByeJohnWeb-1.0-SNAPSHOT\".\"env/za.co.gbj.UserController/userService\" ]","jboss.deployment.subunit.\"GoodByeJohnEAR.ear\".\"GoodByeJohnWeb-1.0-SNAPSHOT.war\".jndiDependencyService missing [ jboss.naming.context.java.module.GoodByeJohnEAR.\"GoodByeJohnWeb-1.0-SNAPSHOT\".\"env/za.co.gbj.UserController/userService\" ]","jboss.naming.context.java.module.GoodByeJohnEAR.\"GoodByeJohnWeb-1.0-SNAPSHOT\".\"env/za.co.gbj.UserController/userService\".jboss.deployment.subunit.\"GoodByeJohnEAR.ear\".\"GoodByeJohnWeb-1.0-SNAPSHOT.war\".module.GoodByeJohnEAR.\"GoodByeJohnWeb-1.0-SNAPSHOT\".2 missing [ jboss.naming.context.java.module.GoodByeJohnEAR.\"GoodByeJohnWeb-1.0-SNAPSHOT\".env/UserService ]"]} 09:03:50,576 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) Starting deployment of "GoodByeJohnEAR.ear" 09:03:50,670 INFO [org.jboss.as.server.deployment] (MSC service thread 1-3) Starting deployment of "GoodByeJohnWeb-1.0-SNAPSHOT.war" 09:03:50,670 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) Starting deployment of "GoodByeJohnEJB-1.0-SNAPSHOT.jar" 09:03:51,367 WARN [org.jboss.as.server.deployment.service-loader] (MSC service thread 1-2) Encountered invalid class name "com.sun.faces.vendor.Tomcat6InjectionProvider:org.apache.catalina.util.DefaultAnnotationProcessor" for service type "com.sun.faces.spi.injectionprovider" 09:03:51,367 WARN [org.jboss.as.server.deployment.service-loader] (MSC service thread 1-2) Encountered invalid class name "com.sun.faces.vendor.Jetty6InjectionProvider:org.mortbay.jetty.plus.annotation.InjectionCollection" for service type "com.sun.faces.spi.injectionprovider" 09:03:51,375 INFO [org.jboss.as.ejb3.deployment.processors.EjbJndiBindingsDeploymentUnitProcessor] (MSC service thread 1-8) JNDI bindings for session bean named UserFacadeBean in deployment unit subdeployment "GoodByeJohnEJB-1.0-SNAPSHOT.jar" of deployment "GoodByeJohnEAR.ear" are as follows: java:global/GoodByeJohnEAR/GoodByeJohnEJB-1.0-SNAPSHOT/UserFacadeBean!za.co.gbj.UserFacadeService java:app/GoodByeJohnEJB-1.0-SNAPSHOT/UserFacadeBean!za.co.gbj.UserFacadeService java:module/UserFacadeBean!za.co.gbj.UserFacadeService java:global/GoodByeJohnEAR/GoodByeJohnEJB-1.0-SNAPSHOT/UserFacadeBean java:app/GoodByeJohnEJB-1.0-SNAPSHOT/UserFacadeBean java:module/UserFacadeBean 09:03:51,406 INFO [org.jboss.as.ejb3.deployment.processors.EjbJndiBindingsDeploymentUnitProcessor] (MSC service thread 1-4) JNDI bindings for session bean named UserFacadeBean in deployment unit subdeployment "GoodByeJohnWeb-1.0-SNAPSHOT.war" of deployment "GoodByeJohnEAR.ear" are as follows: java:global/GoodByeJohnEAR/GoodByeJohnWeb-1.0-SNAPSHOT/UserFacadeBean!za.co.gbj.UserFacadeService java:app/GoodByeJohnWeb-1.0-SNAPSHOT/UserFacadeBean!za.co.gbj.UserFacadeService java:module/UserFacadeBean!za.co.gbj.UserFacadeService java:global/GoodByeJohnEAR/GoodByeJohnWeb-1.0-SNAPSHOT/UserFacadeBean java:app/GoodByeJohnWeb-1.0-SNAPSHOT/UserFacadeBean java:module/UserFacadeBean 09:03:51,577 INFO [org.jboss.as.controller] (DeploymentScanner-threads - 1) Service status report New missing/unsatisfied dependencies: service jboss.naming.context.java.module.GoodByeJohnEAR."GoodByeJohnWeb-1.0-SNAPSHOT".env/UserService (missing) service jboss.naming.context.java.module.GoodByeJohnEAR."GoodByeJohnWeb-1.0-SNAPSHOT"."env/za.co.gbj.UserController/userService" (missing) Please assist!

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  • how to localize a table with multiple text entries?

    - by rap-uvic
    Hello, I'm writing a web app which will allow creation of events. An event can have a title as well as a description amongst other things. The app needs to be multilingual. So I have 4 tables for localization: ResourceTypes, ResourceKeys, Resources, and Locales. A resource key can have multiple values in Resources table for different locales. So Resources is a many to many table between ResourceKeys and Locales. So in the event table I want to have a resourceKey for its title as well as a resourceKey for its description. So my question is, is it OK from database-design perspective to have two foreign keys from a table into another table? Has anybody used a better approach in such a scenario?

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  • abstract class NumberFormat - very confuse about getInstance()

    - by Alex
    Hi, I'm new to Java and I have a beginner question: NumberFormat is an abstract class and so I assume I can't make an instance of it. But there is a public static (factory?) method getInstance() that allow me to do NumberFormat nf = NumberFormat.getInstance(); I'm quite confuse. I'll be glad if someone could give me hints on: 1) If there is a public method to get an instance of this abstract class, why don't we have also a constructor? 2) This is an abstract class ; how can we have this static method giving us an instance of the class? 3) Why choosing such a design? If I assume it's possible to have an instance of an abstract class (???), I don't get why this class should be abstract at all. Thank you.

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  • Jquery getJSON() doesn't work when trying to get data from java server on localhost

    - by bellesebastien
    The whole day yesterday I've been trying to solve this but it's proven to be very challenging for me. I'm trying to use this JS to get information from a java application I wrote. $(document).ready(function() { $.getJSON('http://localhost/custest?callback=?', function(json) { alert('OK'); $('.result').html(json.description); }); }); The Java application uses httpServer and is very basic. When I access the page 'http://localhost/custest?callback=?' with Firefox, the browser shows me the server is sending me json data and asks with what to open it with, but when I try it from a webpage using the JS above it doesn't work. The getJSON call is not successful, the alert("ok") doesn't popup at all. If it replace "http://localhost/custest?callback=?" in the JS with "http://twitter.com/users/usejquery.json?callback=?" everything works fine. An interesting thing is that if I send malformed JSON from my java server Firebug gives an error and tells me what is missing from the JSON so that mean the browser is receiving the JSON data, but when I send it correct a JSON string nothing happens, no errors, not even the alert() opens. I'm adding the headers in case you think these could be relevant. http://localhost/custest?callback=jsonp1274691110349 GET /custest?callback=jsonp1274691110349 HTTP/1.1 Host: localhost User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.2.3) Gecko/20100401 Firefox/3.6.3 Accept: */* Accept-Language: en-us,en;q=0.5 Accept-Encoding: gzip,deflate Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7 Keep-Alive: 115 Connection: keep-alive HTTP/1.1 200 OK Transfer-Encoding: chunked Content-Type: application/json Thanks for your help

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  • abstract class NumberFormat - very confused about getInstance()

    - by Alex
    Hi, I'm new to Java and I have a beginner question: NumberFormat is an abstract class and so I assume I can't make an instance of it. But there is a public static (factory?) method getInstance() that allow me to do NumberFormat nf = NumberFormat.getInstance(); I'm quite confuse. I'll be glad if someone could give me hints on: 1) If there is a public method to get an instance of this abstract class, why don't we have also a constructor? 2) This is an abstract class ; how can we have this static method giving us an instance of the class? 3) Why choosing such a design? If I assume it's possible to have an instance of an abstract class (???), I don't get why this class should be abstract at all. Thank you.

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  • More issues with IntelliJ 9.0.1 "Hello World" in Scala - Predef version 5.0 vs 4.1

    - by Alex R
    Any ideas what could cause this? Scala signature Predef has wrong version Expected 5.0 found: 4.1 in .... scala-library.jar I tried both versions 2.7.6 and 2.8 RC1 of scala-*.jar, the result was the same. JDK is 1.6.u20. UPDATE Today uninstalled IntelliJ 9.0.1, and installed 9.0.2 Early Availability, with the 4/14 stable version of the Scala plug-in. Then I setup a project from scratch through the wizards: new project from scratch JDK is 1.6.u20 accept the default (project) instead of global / module accept the download of Scala 2.8.0beta1 into project's lib folder Created a new class: object hello { def main(args: Array[String]) { println("hello: " + args); } } For my efforts, I now have a brand-new error :) Here it is: Scalac internal error: class java.lang.ClassNotFoundException [java.net.URLClassLoader$1.run(URLClassLoader.java:202), java.security.AccessController.doPrivileged(Native Method), java.net.URLClassLoader.findClass(URLClassLoader.java:190), java.lang.ClassLoader.loadClass(ClassLoader.java:307), sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301), java.lang.ClassLoader.loadClass(ClassLoader.java:248), java.lang.Class.forName0(Native Method), java.lang.Class.forName(Class.java:169), org.jetbrains.plugins.scala.compiler.rt.ScalacRunner.main(ScalacRunner.java:72)] Thanks

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  • Postgresql - one database for everyone, or one-database per customer

    - by user337876
    I'm working on a web-based business application where each customer will need to have their own data (think basecamphq.com type model) For scalability and ease-of-upgrades, I'd prefer to have a single database where each customer gets a filtered version of the data. The problem is how to guarantee that they stay sandboxed to their own data. Trying to enforce it in code seems like a disaster waiting to happen. I know Oracle has a way to append a where clause to every query based on a login id, but does Postgresql have anything similar? If not, is there a different design pattern I could use (like creating a view of each table for each customer that filters)? Worse case scenario, what is the performance/memory overhead of having 1000 100M databases vs having a single 1Tb database? I will need to provide backup/restore functionality on a per-customer basis which is dead-simple on a single database but quite a bit trickier if they are sharing the database with other customers.

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  • jvm version for Websphere 6.1.0.23on Solaris

    - by dr jerry
    Hi I'm at big financial institute and we've an application running on Websphere 6.1. on Solaris. Due to MQ Connectivity we had to install fixpack 6.1.0.23. Unfortunately this broke an ejb (1.1) which is still there as legacy (Test missed it). [3/23/10 11:33:18:703 CET] 00000055 EJBContainerI E WSVR0068E: Attempt to start EnterpriseBean EventRisk_1.0.0#EventRiskEJB.jar#PolicyDataManager failed with exception: java.lang.NoSuchMethodError: com.ibm.ejs.csi.ResRefListImpl.(Lorg/eclipse/jst/j2ee/ejb/EnterpriseBean;Lcom/ibm/ejs/models/base/bindings/ejbbnd/EnterpriseBeanBinding;Lcom/ibm/ejs/models/base/extensions/ejbext/EnterpriseBeanExtension;)V at com.ibm.ws.metadata.ejb.EJBMDOrchestrator.finishBMDInit(EJBMDOrchestrator.java:1364) at com.ibm.ws.runtime.component.EJBContainerImpl.finishDeferredBeanMetaData(EJBContainerImpl.java:4829) at com.ibm.ws.runtime.component.EJBContainerImpl$3.run(EJBContainerImpl.java:4631) at java.security.AccessController.doPrivileged(Native Method) at com.ibm.ws.security.util.AccessController.doPrivileged(AccessController.java:125) at com.ibm.ws.runtime.component.EJBContainerImpl.initializeDeferredEJB(EJBContainerImpl.java:4627) at com.ibm.ejs.container.HomeOfHomes.getHome(HomeOfHomes.java:390) at com.ibm.ejs.container.HomeOfHomes.internalCreateWrapper(HomeOfHomes.java:938) at com.ibm.ejs.container.EJSContainer.createWrapper(EJSContainer.java:4783) at com.ibm.ejs.container.WrapperManager.faultOnKey(WrapperManager.java:545) at com.ibm.ejs.util.cache.Cache.findAndFault(Cache.java:498) at com.ibm.ejs.container.WrapperManager.keyToObject(WrapperManager.java:489) We cannot reproduce the issue on our desktop boxes (it all works fine there) and we do not have direct access to our the Solaris machines (dependent on the deployment department) we do suspect a discrepancy on the jvm but we're not sure. My question is two fold: can you confirm IBM's statement that fixpack 6.1.0.23 for solaris indeed runs on jvm 1.5.0_17b04 our installation tells us ./java -version java version "1.5.0_13" But deploy department is not eager to investigate. Do you see some other solution, apart from hiring big blue's con$ultancy? kind regards, Jeroen.

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  • How can I enjoy or avoid designing every web application I make ?

    - by schmrz
    I know this sounds silly, but I'm having huge problems (ok, not that huge, but still...) problems when I get an idea for a web project, small or big. The instant turn off is when I remember that I have to code the html/css by hand again and again. I like programming a lot more that designing web sites, and I simply don't enjoy designing them as much as I enjoy programming them. With that said, I also prefer simple and minimalistic designs. What is your approach in web design, how do you make it enjoyable (at least a little bit)?

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  • Usage of putty in command line from Hudson

    - by kij
    Hi, I'm trying to use putty in command line from an hudson job. The command is the following one: putty -ssh -2 -P 22 USERNAME@SERVER_ADDR -pw PASS -m command.txt Where 'command.txt' is a shell script to execute in the server through SSH. If i launch this command from the Window command prompt, it works, the shell script is executed on the server machine. If i launch a build of the hudson job configured with this batch command, it doesn't work. The build is running... and running... and running.. without doing anything, and i have to stop it manually. So my question is: Is it possible to launch an external programm (i.e. putty) from an hudson job ? ps: i tried SSH plugin but... not a really good plugin (pre/post build, fail status of the commands launched not caught by hudson, etc.) Thanks in advance for your help. Best regards. kij EDIT: These are the build logs: [workspace] $ cmd /c call C:\WINDOWS\TEMP\hudson7429256014041663539.bat C:\Hudson\jobs\Artifact deployer\workspace>putty -ssh -2 -P 22 USER@SERV_ADD -pw PASS -m com.txt Le build a été annulé Finished: ABORTED And the Hudson.err.log file at the same time (after a stop): 3 juin 2010 18:27:28 hudson.model.Run run INFO: Artifact deployer #6 aborted java.lang.InterruptedException at java.lang.ProcessImpl.waitFor(Native Method) at hudson.Proc$LocalProc.join(Proc.java:179) at hudson.Launcher$ProcStarter.join(Launcher.java:278) at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:83) at hudson.tasks.CommandInterpreter.perform(CommandInterpreter.java:58) at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:19) at hudson.model.AbstractBuild$AbstractRunner.perform(AbstractBuild.java:601) at hudson.model.Build$RunnerImpl.build(Build.java:174) at hudson.model.Build$RunnerImpl.doRun(Build.java:138) at hudson.model.AbstractBuild$AbstractRunner.run(AbstractBuild.java:416) at hudson.model.Run.run(Run.java:1241) at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:46) at hudson.model.ResourceController.execute(ResourceController.java:88) at hudson.model.Executor.run(Executor.java:124) My shell script only write "hello" in a "hello.txt" file on the server, and nothing is done.

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  • How do you use Linq2Sql in your applications ?

    - by this. __curious_geek
    I'm recently migrating to Linq2Sql and all my future projects would be done in Linq2Sql. Having said that, I researched a lot on how to properly plug-in Linq2Sql in application design. what to put at what layer ? Should I use DTOs over Linq2Sql entities ? I did not find any rock-solid material that really talked about one single thing and everyone had their own opinions and I found all of them justified right from their arguments. I'm looking forward to your ideas on how to integrate/use Linq2Sql in projects. My priority is maintenance[it should be maintenable and when multiple people work on same project] and scalabilty [it should have scope of evolution]. Thanks.

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  • Views performance in MySQL for denormalization

    - by Gianluca Bargelli
    I am currently writing my truly first PHP Application and i would like to know how to project/design/implement MySQL Views properly; In my particular case User data is spread across several tables (as a consequence of Database Normalization) and i was thinking to use a View to group data into one large table: CREATE VIEW `Users_Merged` ( name, surname, email, phone, role ) AS ( SELECT name, surname, email, phone, 'Customer' FROM `Customer` ) UNION ( SELECT name, surname, email, tel, 'Admin' FROM `Administrator` ) UNION ( SELECT name, surname, email, tel, 'Manager' FROM `manager` ); This way i can use the View's data from the PHP app easily but i don't really know how much this can affect performance. For example: SELECT * from `Users_Merged` WHERE role = 'Admin'; Is the right way to filter view's data or should i filter BEFORE creating the view itself? (I need this to have a list of users and the functionality to filter them by role). EDIT Specifically what i'm trying to obtain is Denormalization of three tables into one. Is my solution correct? See Denormalization on wikipedia

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  • e-shop implementation: Status for Orders?

    - by Guillermo
    Hello Again my fellow programmers out there, I'm designing and programming from scratch a online shop. It has a Module to manage "Orders" that are recieved via the frontend. I'm needing to have a status to know whats happening with an order in s certain moment, let's say the statuses are: Pending Payment Confirmed - Awaiting shipment Shipped Cancelled My question is a simple one, but is very important to decide on the store design, and is: What would you do so store this status: Would you create a column for it in the Orders table or would you just "calculate" the status of each order depending if payments has been recieved or shipments has been made for every order? (except I suppose for a is_cancelled column) What would be the best approach to model this kind of problem? PD: I even wish in the future to have these statuses configurable buy other clientes using the same software..

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