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  • Auto increment with a Unit Of Work

    - by Derick
    Context I'm building a persistence layer to abstract different types of databases that I'll be needing. On the relational part I have mySQL, Oracle and PostgreSQL. Let's take the following simplified MySQL tables: CREATE TABLE Contact ( ID varchar(15), NAME varchar(30) ); CREATE TABLE Address ( ID varchar(15), CONTACT_ID varchar(15), NAME varchar(50) ); I use code to generate system specific alpha numeric unique ID's fitting 15 chars in this case. Thus, if I insert a Contact record with it's Addresses I have my generated Contact.ID and Address.CONTACT_IDs before committing. I've created a Unit of Work (amongst others) as per Martin Fowler's patterns to add transaction support. I'm using a key based Identity Map in the UoW to track the changed records in memory. It works like a charm for the scenario above, all pretty standard stuff so far. The question scenario comes in when I have a database that is not under my control and the ID fields are auto-increment (or in Oracle sequences). In this case I do not have the db generated Contact.ID beforehand, so when I create my Address I do not have a value for Address.CONTACT_ID. The transaction has not been started on the DB session since all is kept in the Identity Map in memory. Question: What is a good approach to address this? (Avoiding unnecessary db round trips) Some ideas: Retrieve the last ID: I can do a call to the database to retrieve the last Id like: SELECT Auto_increment FROM information_schema.tables WHERE table_name='Contact'; But this is MySQL specific and probably something similar can be done for the other databases. If do this then would need to do the 1st insert, get the ID and then update the children (Address.CONTACT_IDs) – all in the current transaction context.

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  • MSMQ - Message Queue Abstraction and Pattern

    - by Maxim Gershkovich
    Hi All, Let me define the problem first and why a messagequeue has been chosen. I have a datalayer that will be transactional and EXTREMELY insert heavy and rather then attempt to deal with these issues when they occur I am hoping to implement my application from the ground up with this in mind. I have decided to tackle this problem by using the Microsoft Message Queue and perform inserts as time permits asynchronously. However I quickly ran into a problem. Certain inserts that I perform may need to be recalled (ie: retrieved) immediately (imagine this is for POS system and what happens if you need to recall the last transaction - one that still hasn’t been inserted). The way I decided to tackle this problem is by abstracting the MessageQueue and combining it in my data access layer thereby creating the illusion of a single set of data being returned to the user of the datalayer (I have considered the other issues that occur in such a scenario (ie: essentially dirty reads and such) and have concluded for my purposes I can control these issues). However this is where things get a little nasty... I’ve worked out how to get the messages back and such (trivial enough problem) but where I am stuck is; how do I create a generic (or at least somewhat generic) way of querying my message queue? One where I can minimize the duplication between the SQL queries and MessageQueue queries. I have considered using LINQ (but have very limited understanding of the technology) and have also attempted an implementation with Predicates which so far is pretty smelly. Are there any patterns for such a problem that I can utilize? Am I going about this the wrong way? Does anyone have an of their own ideas about how I can tackle this problem? Does anyone even understand what I am talking about? :-) Any and ALL input would be highly appreciated and seriously considered… Thanks again.

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  • StringIndexOutOfBoundsException error in main method

    - by Ro Siv
    I am obtaining a StringIndexOutOfBoundsError when running my main method. Here is the output of my program in the command line. "Please enter the shift, 1 for day, 2 for night" 1 "you entered a number for the shift" "Please enter the hourly pay Rate" 2 "you entered a number for the pay Rate" "Please enter the employees name" brenda "cat6b" "your value you entered is correct 0-9 or a - z" "Please enter the employee number" 100e "cat41" "your value you entered is correct 0-9 or a - z" "Please enter current date in XXYYZZZZ format, X is day, Y is month, Z is year" 10203933 "cat81 " "your value you entered is correct 0-9 or a - z" 90 1 valye of array is 1 81 0 value of array is 0 82 2 value of array is 2 83 0 value of array is 0 84 3 value of array is 3 85 9 value of array is 9 86 3 value of array is 3 87 3 value of array is 3 "Exception in thread "main" java.lang.StringIndexOutOfBoundsException: String index out of range: 8 at java.lang.String.charAt(String.java:658) at ProductionWorker<init>(ProductionWorker.java:66) at labBookFiftyFour.main(labBookFiftyFour.java:58)" "Press any key to continue . . ." Ignore the cat parts in the code, i was using a println statement to test the code. Ignore the value of array output as well, as i wanted to use an array in the program later on. Here is my main method. import java.math.*; import java.text.DecimalFormat; import java.io.*; import java.util.*; public class labBookFiftyFour { public static void main(String[] args) { Scanner myInput = new Scanner(System.in); int shift = -1; double pRate = -2; String name = " "; String number = " "; String date = " "; while(shift < 0 || pRate < 0 ) { System.out.println("Please enter the shift, 1 for day, 2 for night"); if(myInput.hasNextInt()){ System.out.println("you entered a number for the shift"); shift = myInput.nextInt(); } System.out.println("Please enter the hourly pay Rate"); if(myInput.hasNextDouble()){ System.out.println("you entered a number for the pay Rate"); pRate = myInput.nextDouble(); } else if (myInput.hasNext()) { System.out.println("Please enter a proper value"); myInput.next(); } else { System.err.println("No more input"); System.exit(1); } } myInput.nextLine(); //consume newLine System.out.println("Please enter the employees name"); name = myInput.nextLine(); //use your isValid method if(isValid(name)) { System.out.println("your value you entered is correct 0-9 or a - z "); } System.out.println("Please enter the employee number"); number = myInput.nextLine(); //use your isValid method if(isValid(number)) { System.out.println("your value you entered is correct 0-9 or a - z "); } System.out.println("Please enter current date in XXYYZZZZ format, X is day, Y is month, Z is year"); date = myInput.nextLine(); //use your isValid method if(isValid(date)) { System.out.println("your value you entered is correct 0-9 or a - z "); } ProductionWorker myWorker = new ProductionWorker(shift, pRate, name, number, date); //int day and night , double payRate System.out.println("THis is the shift " + myWorker.getShift() + " This is the pay Rate " + myWorker.getPRate() + " " + myWorker.getName() + " " + myWorker.getNumber() + " " + myWorker.getDate()); } //Made this method for testing String input for 0-9 or a - z values , put AFTER main method, but before end of class public static boolean isValid(String stringName) //This method has to be static, for some reason? { System.out.println("cat" + stringName.length() + stringName.charAt(0)); boolean flag = true; int index = 0; while(index < stringName.length()) { if(Character.isLetterOrDigit(stringName.charAt(index))) { flag = true; } else { flag = false; } ++index; } return flag; } } Here is my employeeOne. java Superclass public class employeeOne { private String name; private String number; private String date; public employeeOne(String name, String number, String date) { this.name = name; this.number = number; this.date = date; } public String getName() { return name; } public String getNumber() { return number; } public String getDate() { return date; } } Here is my ProductionWorker.java subclass, which extends employeeOne public class ProductionWorker extends employeeOne { private int shift; //shift represents day or night, day = 1, night = 2 private double pRate; //hourly pay rate public ProductionWorker(int shift, double pRate, String name, String number, String date) { super(name, number, date); this.shift = shift; if(this.shift >= 3 || this.shift <= 0) { System.out.println("You entered an out of bounds shift date, enter 1 for day or 2 for night, else shift will be day"); this.shift = 1; } this.pRate = pRate; boolean goodSoFar = true; int indexNum = 0; int indexDate = 0; if(name.length() <= 10 && number.length() <= 4 && date.length() < 9 ) { goodSoFar = true; } else { goodSoFar = false; } while(goodSoFar && indexNum < 3) //XXXL XXX digits 1-9, L is a letter A -M { if(Character.isDigit(number.charAt(indexNum))) { goodSoFar = true; } else { goodSoFar = false; } ++indexNum; } while(goodSoFar && indexNum < 4) { if(Character.isLetter(number.charAt(indexNum))) { goodSoFar = true; } else if(Character.isDigit(number.charAt(indexNum))) { goodSoFar = false; } else if(Character.isDigit(number.charAt(indexNum)) == false && Character.isLetter(number.charAt(indexNum)) == false) { goodSoFar = false; } ++indexNum; } int[] dateValues = new int[date.length()]; while(goodSoFar && indexDate <= date.length()) //XXYYZZZZ { System.out.println("" + date.length() + indexDate + " " + date.charAt(indexDate)); if(Character.isDigit(date.charAt(indexDate))) { dateValues[indexDate] = Character.getNumericValue(date.charAt(indexDate)); System.out.println("value of array is " + dateValues[indexDate]); ++indexDate; } else { goodSoFar = false; } } if(goodSoFar) { System.out.println("your input is good so far"); } else { System.out.println("your input is wrong for name or number or date"); } } public int getShift() { return shift; } public double getPRate() { return pRate; } }

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  • How to understand other people's CSS architectures?

    - by John
    I am reasonably good with CSS. However, when working with someone else's CSS, it's difficult for me to see the "bigger picture" in their architecture (but i have no problem when working with a CSS sheet I wrote myself). For example, I have no problems using Firebug to isolate and fix cross browser compatibility issues, or fixing a floating issue, or changing the height on a particular element. But if I'm asked to do something drastic such as, "I want the right sidebars of pages A, B, C and D to have a red border. I want the right side bars of pages E, F and G to have a blue border if and only if the user mouses over", then it takes me time a long time to map out all the CSS inheritance rules to see the "bigger picture". For some reason, I don't encounter the same difficulty with backend code. After a quick debriefing of how a feature works, and a quick inspection of the controller and model code, I will feel comfortable with the architecture. I will think, "it's reasonable to assume that there will be an Employee class that inherits from the Person Class that's used by a Department controller". If I discover inconvenient details that aren't consistent with overall architectural style, I am confident that I can hammer things back in place. With someone else's CSS work, it's much harder for me to see the "relationships" between different classes, and when and how the classes are used. When there are many inheritance rules, I feel overwhelmed. I'm having trouble articulating my question and issues... All I want to know is, why is it so much harder for me to see the bigger picture in someone else's CSS architecture than compared to someone else's business logic layer? **Does it have any thing to do with CSS being a relatively new technology, and there aren't many popular design patterns?

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  • What do you call a generalized (non-GUI-related) "Model-View-Controller" architecture?

    - by dcuccia
    I am currently refactoring code that coordinates multiple hardware components for data acquisition, and feeling a bit like I'm recreating the wheel. In particular, an MVC-like pattern seems to be emerging. Except, this has nothing to do with a GUI and I'm worried that I'm forcing this particular pattern where another might be more appropriate. Here's my scenario: Individual hardware "component" classes obey interface contracts for each hardware type. Previously, component instances were orchestrated by a single monolithic InstrumentController class, which relied heavily on configuration + branching logic for executing a specific acquisition sequence. After an iteration, I have a separate controller for each component, with these controllers all managed by a small InstrumentControllerBase (or its derivatives). The composite system will receive "input" either programmatically or via inter-hardware component triggering - in either case these interactions are routed to, and handled by, the appropriate controller. So, I have something that feels MVC-esque, but I don't know if that's because I'm forcing the point. With little direct MVC experience in application development, it's hard to know if I'm just trying to make my scenario fit MVC, where another pattern might be a good alternative or complimentary. My problem is, search results and wiki documentation of these family of patterns seems to immediately drop me into GUI-specific discussions. I understand "M means Model data and the V means View" - but do you call the superset pattern? Component-Commander-Controller? Whence can I exhume examples exemplary?

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  • Large Switch statements: Bad OOP?

    - by Mystere Man
    I've always been of the opinion that large switch statements are a symptom of bad OOP design. In the past, I've read articles that discuss this topic and they have provided altnerative OOP based approaches, typically based on polymorphism to instantiate the right object to handle the case. I'm now in a situation that has a monsterous switch statement based on a stream of data from a TCP socket in which the protocol consists of basically newline terminated command, followed by lines of data, followed by an end marker. The command can be one of 100 different commands, so I'd like to find a way to reduce this monster switch statement to something more manageable. I've done some googling to find the solutions I recall, but sadly, Google has become a wasteland of irrelevant results for many kinds of queries these days. Are there any patterns for this sort of problem? Any suggestions on possible implementations? One thought I had was to use a dictionary lookup, matching the command text to the object type to instantiate. This has the nice advantage of merely creating a new object and inserting a new command/type in the table for any new commands. However, this also has the problem of type explosion. I now need 100 new classes, plus I have to find a way to interface them cleanly to the data model. Is the "one true switch statement" really the way to go? I'd appreciate your thoughts, opinions, or comments.

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  • NullPointerException when showing JFileChooser

    - by Geo
    I show a JFileChooser with this snippet: public File getDestination() { JFileChooser chooser = new JFileChooser(); chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY); int option = chooser.showSaveDialog(null); if(option == JFileChooser.APPROVE_OPTION) { return chooser.getSelectedFile().getAbsolutePath(); } return new File("."); } Usually, the first time it's showed, it displays & works correctly. The second time, it will always throw this exception: Exception in thread "Basic L&F File Loading Thread" java.lang.NullPointerException at sun.awt.shell.Win32ShellFolder2.pidlsEqual(Unknown Source) at sun.awt.shell.Win32ShellFolder2.equals(Unknown Source) at sun.awt.shell.Win32ShellFolderManager2.isFileSystemRoot(Unknown Source) at sun.awt.shell.ShellFolder.isFileSystemRoot(Unknown Source) at javax.swing.filechooser.FileSystemView.isFileSystemRoot(Unknown Source) at javax.swing.filechooser.WindowsFileSystemView.isTraversable(Unknown Source) at javax.swing.JFileChooser.isTraversable(Unknown Source) at javax.swing.plaf.basic.BasicDirectoryModel$LoadFilesThread.run0(Unknown Source) at javax.swing.plaf.basic.BasicDirectoryModel$LoadFilesThread.run(Unknown Source) Java -version says: java version "1.6.0_20" Java(TM) SE Runtime Environment (build 1.6.0_20-b02) Java HotSpot(TM) Client VM (build 16.3-b01, mixed mode, sharing) And the thread I found here says I should downgrade the Java version. Should I follow their advice, or is there something I could have done wrong?

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  • cannot load JSTL taglib within embedded Jetty server

    - by fthompson
    I am writing a web application that runs within an embedded Jetty instance. When I attempt to execute a JSTL statement, I receive the following exception: org.apache.jasper.JasperException: /index.jsp(1,63) PWC6188: The absolute uri: http://java.sun.com/jsp/jstl/core cannot be resolved in either web.xml or the jar files deployed with this application I have the following jars on the classpath ant-1.6.5.jar ant-1.7.1.jar ant-launcher-1.7.1.jar core-3.1.1.jar jetty-6.1.22.jar jetty-util-6.1.22.jar jsp-2.1-6.1.14.jar jsp-api-2.1.jar jstl-1.2.jar servlet-api-2.5-20081211.jar servlet-api-2.5-6.1.14.jar standard-1.1.2.jar My web.xml looks like this: <?xml version="1.0" encoding="ISO-8859-1"?> <web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee h77p://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd" version="2.4"> <display-name>test</display-name> </web-app> My code looks like this: <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <body> <h2>Hello World!</h2> <%= new java.util.Date() %><br/> ${1+2}<br/> <c:out var="${5+9}"/><br/> </body> </html> I started my embedded Jetty server like this: Server server = new Server(80); WebAppContext context = new WebAppContext("pig-1.0-SNAPSHOT.war","/"); server.addHandler(context); server.start(); I spent the past two days experimenting with various combinations of jar files, web.xml configurations, and tag library declarations, but to no avail. How can I get an embedded Jetty server up and running with full JSTL support?

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  • How to avoid session sharing provided by IE8 programatically in java/j2ee application ?

    - by Idiot
    Microsoft, in an effort to make Internet Explorer 8 "more stable" and “faster”, have changed the underlying architecture of the browser and introduced a function called "Loosely-Coupled IE" (LCIE) which works on session sharing across TAB and new instances. But session sharing may be fatal when some one is trying to do two different things at a time with the same application, e.g. like someone want to book one forward journey ticket and one return ticket at a time, at that time he will book 2 same tickets what he has not intended to. PROBABLE SOLUTION ON IT While creating new window Instead of creating by clicking on icon or Ctrl+N we should use File - New Session it will not happen. You can make a registry change on the client PC - adding the following. [HKEY_CURRENT_USER\Software\Microsoft\Internet Explorer\Main] “TabProcGrowth" = dword : 00000000 Will disable "Loosely Couple IE8"; IE8 then works as previous versions of IE. But how i will do it programatically ?

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  • how to pass the parameters to the urlconnection in java/android?

    - by androidbase
    hi all, i can establish a connection using HttpUrlConnection. my code below. client = new DefaultHttpClient(); URL action_url = new URL(actionUrl); conn = (HttpURLConnection) action_url.openConnection(); conn.setDoOutput(true); conn.setDoInput(true); conn.setRequestProperty("domain", "bschool.hbs.edu"); conn.setRequestProperty("userType", "2"); conn.setRequestProperty("referer", "http://www.alumni.hbs.edu/"); conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); conn.setRequestMethod(HttpPost.METHOD_NAME); DataOutputStream ds = new DataOutputStream(conn.getOutputStream()); String content = "username=username1&password=password11"; Log.v(TAG, "content: " + content); ds.writeBytes(content); ds.flush(); ds.close(); InputStream in = conn.getInputStream();//**getting filenotfound exception here.** BufferedReader reader = new BufferedReader( new InputStreamReader(in)); StringBuilder str1 = new StringBuilder(); String line = null; while ((line = reader.readLine()) != null) { str1.append(line); Log.v(TAG, "line:" + line); } in.close(); s = str1.toString(); getting filenotfound exception. dont know why? else give me some suggestion to pass username and passwrod parameter to the url by code..

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  • Really slow obtaining font metrics.

    - by Artur
    So the problem I have is that I start my application by displaying a simple menu. To size and align the text correctly I need to obtain font metrics and I cannot find a way to do it quickly. I tested my program and it looks like whatever method I use to obtain font metrics the first call takes over 500 milliseconds!? Because of it the time it takes to start-up my application is much longer than necessary. I don't know if it is platform specific or not, but just in case, I'm using Mac OS 10.6.2 on MacBook Pro (hardware isn't an issue here). If you know a way of obtaining font metrics quicker please help. I tried these 3 methods for obtaining the font metrics and the first call is always very slow, no matter which method I choose. import java.awt.Font; import java.awt.FontMetrics; import java.awt.Graphics; import java.awt.Graphics2D; import java.awt.font.FontRenderContext; import java.awt.font.LineMetrics; import javax.swing.JFrame; public class FontMetricsTest extends JFrame { public FontMetricsTest() { setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } @Override public void paint(Graphics g) { Graphics2D g2 = (Graphics2D) g; Font font = new Font("Dialog", Font.BOLD, 10); long start = System.currentTimeMillis(); FontMetrics fontMetrics = g2.getFontMetrics(font); // LineMetrics fontMetrics1 = // font.getLineMetrics("X", new FontRenderContext(null, false, false)); // FontMetrics fontMetrics2 = g.getFontMetrics(); long end = System.currentTimeMillis(); System.out.println(end - start); g2.setFont(font); } public static void main(String[] args) { new FontMetricsTest(); } }

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  • How do I parse JSON from a Java HTTPResponse?

    - by Joe Ludwig
    I have an HttpResponse object for a web request I just made. The response is in the JSON format, so I need to parse it. I can do it in an absurdly complex way, but it seems like there must be a better way. Is this really the best I can do? HttpResponse response; // some response object Reader in = new BufferedReader( new InputStreamReader(response.getEntity().getContent(), "UTF-8")); StringBuilder builder= new StringBuilder(); char[] buf = new char[1000]; int l = 0; while (l >= 0) { builder.append(buf, 0, l); l = in.read(buf); } JSONTokener tokener = new JSONTokener( builder.toString() ); JSONArray finalResult = new JSONArray( tokener ); I'm on Android if that makes any difference.

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  • Opening a LWJGL window from a SWT app on Mac

    - by TomA
    I have a SWT app that opens a OpenGL window (using the LWJGL library) after a button is pressed. Works fine on Windows. On Mac, I get this error: 2010-03-05 02:28:25.315 java[1315:a07] [Java CocoaComponent compatibility mode]: Enabled 2010-03-05 02:28:25.316 java[1315:a07] [Java CocoaComponent compatibility mode]: Setting timeout for SWT to 0.100000 2010-03-05 02:28:25.317 java[1315:a07] Apple AWT Startup Exception : _createMenuRef called with existing principal MenuRef already associated with menu 2010-03-05 02:28:25.318 java[1315:a07] Apple AWT Restarting Native Event Thread The SWT window closes and then the app hangs, with no windows open. It looks like the SWT app doesn't shut down cleanly and leaves it's menu entries associated with it, which prevents the LWJGL window from opening. Mac OS X only wants one application menu. SWT doesn't free it's own menu and LWJGL wants to add another. Facts: A button in the SWT dialog is supposed to close the dialog and open a LWJGL window (org.lwjgl.opengl.Display). The button sets a static variable in the app to tell it what to do next after the SWT window is closed, so the LWJGL window is NOT being opened from a SWT callback directly. The button then closes the SWT window. I don't know the correct way of doing this but tried various combinations of shell.close, shell.dispose, display.close and display.dispose, none of them worked. They all close the window but the error occurs every time. Does anyone know what could be done to make this work?

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  • How to send audio stream via UDP in java?

    - by Nob Venoda
    Hi to all :) I have a problem, i have set MediaLocator to microphone input, and then created Player. I need to grab that sound from the microphone, encode it to some lower quality stream, and send it as a datagram packet via UDP. Here's the code, i found most of it online and adapted it to my app: public class AudioSender extends Thread { private MediaLocator ml = new MediaLocator("javasound://44100"); private DatagramSocket socket; private boolean transmitting; private Player player; TargetDataLine mic; byte[] buffer; private AudioFormat format; private DatagramSocket datagramSocket(){ try { return new DatagramSocket(); } catch (SocketException ex) { return null; } } private void startMic() { try { format = new AudioFormat(AudioFormat.Encoding.PCM_SIGNED, 8000.0F, 16, 2, 4, 8000.0F, true); DataLine.Info info = new DataLine.Info(TargetDataLine.class, format); mic = (TargetDataLine) AudioSystem.getLine(info); mic.open(format); mic.start(); buffer = new byte[1024]; } catch (LineUnavailableException ex) { Logger.getLogger(AudioSender.class.getName()).log(Level.SEVERE, null, ex); } } private Player createPlayer() { try { return Manager.createRealizedPlayer(ml); } catch (IOException ex) { return null; } catch (NoPlayerException ex) { return null; } catch (CannotRealizeException ex) { return null; } } private void send() { try { mic.read(buffer, 0, 1024); DatagramPacket packet = new DatagramPacket( buffer, buffer.length, InetAddress.getByName(Util.getRemoteIP()), 91); socket.send(packet); } catch (IOException ex) { Logger.getLogger(AudioSender.class.getName()).log(Level.SEVERE, null, ex); } } @Override public void run() { player = createPlayer(); player.start(); socket = datagramSocket(); transmitting = true; startMic(); while (transmitting) { send(); } } public static void main(String[] args) { AudioSender as = new AudioSender(); as.start(); } } And only thing that happens when I run the receiver class, is me hearing this Player from the sender class. And I cant seem to see the connection between TargetDataLine and Player. Basically, I need to get the sound form player, and somehow convert it to bytes[], therefore I can sent it as datagram. Any ideas? Everything is acceptable, as long as it works :)

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  • How can I implement an abstract singleton class in Java?

    - by Simon
    Here is my sample abstract singleton class: public abstract class A { protected static A instance; public static A getInstance() { return instance; } //...rest of my abstract methods... } And here is the concrete implementation: public class B extends A { private B() { } static { instance = new B(); } //...implementations of my abstract methods... } Unfortunately I can't get the static code in class B to execute, so the instance variable never gets set. I have tried this: Class c = B.class; A.getInstance() - returns null; and this ClassLoader.getSystemClassLoader().loadClass("B"); A.getInstance() - return null; Running both these in the eclipse debugger the static code never gets executed. The only way I could find to get the static code executed is to change the accessibility on B's constructor to public, and to call it. I'm using sun-java6-jre on Ubuntu 32bit to run these tests.

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  • Selenium - Could not start Selenium session: Failed to start new browser session: Error while launching browser

    - by Yatendra Goel
    I am new to Selenium. I generated my first java selenium test case and it has compiled successfully. But when I run that test I got the following RuntimeException java.lang.RuntimeException: Could not start Selenium session: Failed to start new browser session: Error while launching browser at com.thoughtworks.selenium.DefaultSelenium.start <DefaultSelenium.java:88> Kindly tell me how can I fix this error. This is the java file I want to run. import com.thoughtworks.selenium.*; import java.util.regex.Pattern; import junit.framework.*; public class orkut extends SeleneseTestCase { public void setUp() throws Exception { setUp("https://www.google.com/", "*chrome"); } public void testOrkut() throws Exception { selenium.setTimeout("10000"); selenium.open("/accounts/ServiceLogin?service=orkut&hl=en-US&rm=false&continue=http%3A%2F%2Fwww.orkut.com%2FRedirLogin%3Fmsg%3D0&cd=IN&skipvpage=true&sendvemail=false"); selenium.type("Email", "username"); selenium.type("Passwd", "password"); selenium.click("signIn"); selenium.selectFrame("orkutFrame"); selenium.click("link=Communities"); selenium.waitForPageToLoad("10000"); } public static Test suite() { return new TestSuite(orkut.class); } public void tearDown(){ selenium.stop(); } public static void main(String args[]) { junit.textui.TestRunner.run(suite()); } } I first started the selenium server through the command prompt and then execute the above java file through another command prompt. Second Question: Can I do right click on a specified place on a webpage with selenium.

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  • How do I determine a best-fit distribution in java?

    - by Eadwacer
    I have a bunch of sets of data (between 50 to 500 points, each of which can take a positive integral value) and need to determine which distribution best describes them. I have done this manually for several of them, but need to automate this going forward. Some of the sets are completely modal (every datum has the value of 15), some are strongly modal or bimodal, some are bell-curves (often skewed and with differing degrees of kertosis/pointiness), some are roughly flat, and there are any number of other possible distributions (possion, power-law, etc.). I need a way to determine which distribution best describes the data and (ideally) also provides me with a fitness metric so that I know how confident I am in the analysis. Existing open-source libraries would be ideal, followed by well documented algorithms that I can implement myself.

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  • OpenCV to JNI how to make it work?

    - by padfoot-4444
    I am tring to use opencv and java for face detection, and in that pursit i found this "JNI2OPENCV" file....but i am confused on how to make it work, can anyone help me? http://img519.imageshack.us/img519/4803/askaj.jpg and the following is the FaceDetection.java `class JNIOpenCV { static { System.loadLibrary("JNI2OpenCV"); } public native int[] detectFace(int minFaceWidth, int minFaceHeight, String cascade, String filename); } public class FaceDetection { private JNIOpenCV myJNIOpenCV; private FaceDetection myFaceDetection; public FaceDetection() { myJNIOpenCV = new JNIOpenCV(); String filename = "lena.jpg"; String cascade = "haarcascade_frontalface_alt.xml"; int[] detectedFaces = myJNIOpenCV.detectFace(40, 40, cascade, filename); int numFaces = detectedFaces.length / 4; System.out.println("numFaces = " + numFaces); for (int i = 0; i < numFaces; i++) { System.out.println("Face " + i + ": " + detectedFaces[4 * i + 0] + " " + detectedFaces[4 * i + 1] + " " + detectedFaces[4 * i + 2] + " " + detectedFaces[4 * i + 3]); } } public static void main(String args[]) { FaceDetection myFaceDetection = new FaceDetection(); } }` CAn anyone tell me how can i make this work on Netbeans?? I tried Google but help on this particular topic is very meger. I have added the whole folder as Llibrary in netbeans project and whe i try to run the file i get the followig wrroes. Exception in thread "main" java.lang.UnsatisfiedLinkError: FaceDetection.JNIOpenCV.detectFace(IILjava/lang/String;Ljava/lang/String;)[I at FaceDetection.JNIOpenCV.detectFace(Native Method) at FaceDetection.FaceDetection.<init>(FaceDetection.java:19) at FaceDetection.FaceDetection.main(FaceDetection.java:29) Java Result: 1 BUILD SUCCESSFUL (total time: 2 seconds) CAn anyone tell me the exact way to work with this? like what all i have to do?

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  • What can I do with Java for Blu Ray or BD-J?

    - by Jay Askren
    I have a Blu Ray player which can connect to the internet to play media from netflix and youtube. I am intrigued by the possibilities of BD-J and wondering just how far the technology can be taken. For instance: Could I write a twitter, facebook, rss reader, or email client? Can I write a game which would allows people to play each other over the web from their own tv? Could I write a DVR app which stored tv shows on the thumbdrive plugged into the player. Can I run my applications from a thumbdrive or do I need to put them on a Blu Ray disk? Does anyone have real experience with BD-J? How do you like it as a development platform? How would you recommend getting started? Can I develop in BD-J using open source tools like Eclipse, Maven, etc...

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  • Implementing RSA-SHA1 signature algorithm in Java (creating a private key for use with OAuth RSA-SHA

    - by The Elite Gentleman
    Hi everyone, As you know, OAuth can support RSA-SHA1 Signature. I have an OAuthSignature interface that has the following method public String sign(String data, String consumerSecret, String tokenSecret) throws GeneralSecurityException; I successfully implemented and tested HMAC-SHA1 Signature (which OAuth Supports) as well as the PLAINTEXT "signature". I have searched google and I have to create a private key if I need to use SHA1withRSA signature: Sample code: /** * Signs the data with the given key and the provided algorithm. */ private static byte[] sign(PrivateKey key, String data) throws GeneralSecurityException { Signature signature = Signature.getInstance("SHA1withRSA"); signature.initSign(key); signature.update(data.getBytes()); return signature.sign(); } Now, How can I take the OAuth key (which is key = consumerSecret&tokenSecret) and create a PrivateKey to use with SHA1withRSA signature? Thanks

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  • Java JMS = HornetQ = javax.jms.JMSSecurityException: Unable to validate user: null ?

    - by jens
    Hello Experts, I am trying for several hours to get the HornetQ Examples running in Eclipse. Using the Standalone Examples everything works fine, but when I run the examples in Eclipse I get the following error: javax.jms.JMSSecurityException: Unable to validate user: null What could this error mean? Where do I have to specify the user? Maybe HornetQ tries to look this user up in "Some Context/Properties" etc , but I do not know where and how to specifiy the user HornetQ is running under. What i did: 1.)Started Default HornetQ Server with the start.sh Script in the ./bin directory 2.)Copied the QueueExample over to eclpise 3.)Did some minor changes in the config files (to have the same Queue Names...) (I also tried to disable security completely by setting: <security-enabled>false</security-enabled> but with no success, always getting the same error. Also when trying to programmatically instance HornetQ only via classes I get this error too). Thank you very much!! Jens

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