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• Javascript to fire event when a key pressed on the Ajax Toolkit Combo box.

  - by Paul Chapman

  I have the following drop down list which is using the Ajax Toolkit to provide a combo box <cc1:ComboBox ID="txtDrug" runat="server" style="font-size:8pt; width:267px;" Font-Size="8pt" DropDownStyle="DropDownList" AutoCompleteMode="SuggestAppend" AutoPostBack="True" ontextchanged="txtDrug_TextChanged" /> Now I need to load this up with approx 7,000 records which takes a considerable time, and effects the response times when the page is posted back and forth. The code which loads these records is as follows; dtDrugs = wsHelper.spGetAllDrugs(); txtDrug.DataValueField = "pkDrugsID"; txtDrug.DataTextField = "drugName"; txtDrug.DataSource = dtDrugs; txtDrug.DataBind(); However if I could get an event to fire when a letter is typed instead of having to load 7000 records it is reduced to less than 50 in most instances. I think this can be done in Javascript. So the question is how can I get an event to fire such that when the form starts there is nothing in the drop down, but as soon as a key is pressed it searches for those records starting with that letter. The .Net side of things I'm sure about - it is the Javascript I'm not. Thanks in advance

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• Can I avoid a threaded UDP socket in Python dropping data?

  - by 666craig

  First off, I'm new to Python and learning on the job, so be gentle! I'm trying to write a threaded Python app for Windows that reads data from a UDP socket (thread-1), writes it to file (thread-2), and displays the live data (thread-3) to a widget (gtk.Image using a gtk.gdk.pixbuf). I'm using queues for communicating data between threads. My problem is that if I start only threads 1 and 3 (so skip the file writing for now), it seems that I lose some data after the first few samples. After this drop it looks fine. Even by letting thread 1 complete before running thread 3, this apparent drop is still there. Apologies for the length of code snippet (I've removed the thread that writes to file), but I felt removing code would just prompt questions. Hope someone can shed some light :-) import socket import threading import Queue import numpy import gtk gtk.gdk.threads_init() import gtk.glade import pygtk class readFromUDPSocket(threading.Thread): def __init__(self, socketUDP, readDataQueue, packetSize, numScans): threading.Thread.__init__(self) self.socketUDP = socketUDP self.readDataQueue = readDataQueue self.packetSize = packetSize self.numScans = numScans def run(self): for scan in range(1, self.numScans + 1): buffer = self.socketUDP.recv(self.packetSize) self.readDataQueue.put(buffer) self.socketUDP.close() print 'myServer finished!' class displayWithGTK(threading.Thread): def __init__(self, displayDataQueue, image, viewArea): threading.Thread.__init__(self) self.displayDataQueue = displayDataQueue self.image = image self.viewWidth = viewArea[0] self.viewHeight = viewArea[1] self.displayData = numpy.zeros((self.viewHeight, self.viewWidth, 3), dtype=numpy.uint16) def run(self): scan = 0 try: while True: if not scan % self.viewWidth: scan = 0 buffer = self.displayDataQueue.get(timeout=0.1) self.displayData[:, scan, 0] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 1] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 2] = numpy.fromstring(buffer, dtype=numpy.uint16) gtk.gdk.threads_enter() self.myPixbuf = gtk.gdk.pixbuf_new_from_data(self.displayData.tostring(), gtk.gdk.COLORSPACE_RGB, False, 8, self.viewWidth, self.viewHeight, self.viewWidth * 3) self.image.set_from_pixbuf(self.myPixbuf) self.image.show() gtk.gdk.threads_leave() scan += 1 except Queue.Empty: print 'myDisplay finished!' pass def quitGUI(obj): print 'Currently active threads: %s' % threading.enumerate() gtk.main_quit() if __name__ == '__main__': # Create socket (IPv4 protocol, datagram (UDP)) and bind to address socketUDP = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) host = '192.168.1.5' port = 1024 socketUDP.bind((host, port)) # Data parameters samplesPerScan = 256 packetsPerSecond = 1200 packetSize = 512 duration = 1 # For now, set a fixed duration to log data numScans = int(packetsPerSecond * duration) # Create array to store data data = numpy.zeros((samplesPerScan, numScans), dtype=numpy.uint16) # Create queue for displaying from readDataQueue = Queue.Queue(numScans) # Build GUI from Glade XML file builder = gtk.Builder() builder.add_from_file('GroundVue.glade') window = builder.get_object('mainwindow') window.connect('destroy', quitGUI) view = builder.get_object('viewport') image = gtk.Image() view.add(image) viewArea = (1200, samplesPerScan) # Instantiate & start threads myServer = readFromUDPSocket(socketUDP, readDataQueue, packetSize, numScans) myDisplay = displayWithGTK(readDataQueue, image, viewArea) myServer.start() myDisplay.start() gtk.gdk.threads_enter() gtk.main() gtk.gdk.threads_leave() print 'gtk.main finished!'

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• Coordinating typedefs and structs in std::multiset (C++)

  - by Sarah

  I'm not a professional programmer, so please don't hesitate to state the obvious. My goal is to use a std::multiset container (typedef EventMultiSet) called currentEvents to organize a list of structs, of type Event, and to have members of class Host occasionally add new Event structs to currentEvents. The structs are supposed to be sorted by one of their members, time. I am not sure how much of what I am trying to do is legal; the g++ compiler reports (in "Host.h") "error: 'EventMultiSet' has not been declared." Here's what I'm doing: // Event.h struct Event { public: bool operator < ( const Event & rhs ) const { return ( time < rhs.time ); } double time; int eventID; int hostID; }; // Host.h ... void calcLifeHist( double, EventMultiSet * ); // produces compiler error ... void addEvent( double, int, int, EventMultiSet * ); // produces compiler error // Host.cpp #include "Event.h" ... // main.cpp #include "Event.h" ... typedef std::multiset< Event, std::less< Event > > EventMultiSet; EventMultiSet currentEvents; EventMultiSet * cePtr = &currentEvents; ... Major questions Where should I include the EventMultiSet typedef? Are my EventMultiSet pointers obviously problematic? Is the compare function within my Event struct (in theory) okay? Thank you very much in advance.

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• Problem with mouse event on a user control (wpf).

  - by csciguy

  All, I have a user control, defined as follows. <UserControl x:Class="IDOView.AnimatedCharacter" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:local="clr-namespace:IDOView" mc:Ignorable="d" Background="Transparent" > <Image Name="displayImage" Height="Auto" Width="Auto" Stretch="Fill" IsHitTestVisible="True"/> The control is added to a main page twice, as follows. <local:customControl x:Name="A1" Height="259" Width="197" DisplayImage="circle.png" Canvas.Left="-279" Canvas.Top="-56" MouseLeftButtonUp="DoA1"> <local:customControl x:Name="A1" Height="259" Width="197" DisplayImage="square.png" Canvas.Left="-209" Canvas.Top="-56" MouseLeftButtonUp="DoA2"> Essentially, about half of the circle is behind the square. I need the square image in this case to pass through events to the circle behind it. The square has an element cut out of it (transparent). What is happening now is that the circle event only registers if I click on the region that is not covered by the square. Surely there has to be a way to bubble this event, or click-through?

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• Is there a way to log every gui event in Delphi?

  - by awmross

  The Delphi debugger is great for debugging linear code, where one function calls other functions in a predictable, linear manner, and we can step through the program line by line. I find the debugger less useful when dealing with event driven gui code, where a single line of code can cause new events to be trigerred, which may in turn trigger other events. In this situation, the 'step through the code' approach doesn't let me see everything that is going on. The way I usually solve this is to 1) guess which events might be part of the problem, then 2) add breakpoints or logging to each of those events. The problem is that this approach is haphazard and time consuming. Is there a switch I can flick in the debugger to say 'log all gui events'? Or is there some code I can add to trap events, something like procedure GuiEventCalled(ev:Event) begin log(ev); ev.call(); end The end result I'm looking for is something like this (for example): FieldA.KeyDown FieldA.KeyPress FieldA.OnChange FieldA.OnExit FieldB.OnEnter This would take all the guesswork out of Delphi gui debugging. I am using Delphi 2010

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• How do I "rebind" the click event after unbind('click') ?

  - by Ben

  I have an anchor tag <a class="next">next</a> made into a "button". Sometimes, this tag needs to be hidden if there is nothing new to show. All works fine if I simply hide the button with .hide() and re-display it with .show(). But I wanted to uses .fadeIn() and .fadeOut() instead. The problem I'm having is that if the user clicks on the button during the fadeOut animation, it can cause problems with the logic I have running the show. The solution I found was to unbind the click event from the button after the original click function begins, and then re-bind it after the animation is complete. $('a.next').click(function() { $(this).unbind('click'); ... // calls some functions, one of which fades out the a.next if needed ... $(this).bind('click'); } the last part of the above example does not work. The click event is not actually re-bound to the anchor. does anyone know the correct way to accomplish this? I'm a self-taught jquery guy, so some of the higher level things like unbind() and bind() are over my head, and the jquery documentation isn't really simple enough for me to understand.

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• Prevent backspace button from navigating back in Sharepoint 2010 and IE

  - by Machinegon

  as a user requirement I have to disable the backspace button from navigating back in the history. I made the following piece of code //Bind back nutton to prevent escaping the page with backspace $j(document).unbind('keydown').bind('keydown', function (event) { var doPrevent = false; if (event.keyCode === 8) { if(event.target == document.body){ if(event.preventDefault()){ event.preventDefault(); } event.stopEvent(); event.returnValue = false; } } }); This is working perfectly in all the browsers except IE8/7. I cannot bind the input types as exceptions because the content editor in sharepoint allows to modify the text in div or paragraph elements etc. The solution is not working in IE8 because the event.target returns the element that is on mouseover when there's no controls that has the focus. All tips will be appreciated. Thanks!!

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• Multiset container appears to stop sorting

  - by Sarah

  I would appreciate help debugging some strange behavior by a multiset container. Occasionally, the container appears to stop sorting. This is an infrequent error, apparent in only some simulations after a long time, and I'm short on ideas. (I'm an amateur programmer--suggestions of all kinds are welcome.) My container is a std::multiset that holds Event structs: typedef std::multiset< Event, std::less< Event > > EventPQ; with the Event structs sorted by their double time members: struct Event { public: explicit Event(double t) : time(t), eventID(), hostID(), s() {} Event(double t, int eid, int hid, int stype) : time(t), eventID( eid ), hostID( hid ), s(stype) {} bool operator < ( const Event & rhs ) const { return ( time < rhs.time ); } double time; ... }; The program iterates through periods of adding events with unordered times to EventPQ currentEvents and then pulling off events in order. Rarely, after some events have been added (with perfectly 'legal' times), events start getting executed out of order. What could make the events ever not get ordered properly? (Or what could mess up the iterator?) I have checked that all the added event times are legitimate (i.e., all exceed the current simulation time), and I have also confirmed that the error does not occur because two events happen to get scheduled for the same time. I'd love suggestions on how to work through this. The code for executing and adding events is below for the curious: double t = 0.0; double nextTimeStep = t + EPID_DELTA_T; EventPQ::iterator eventIter = currentEvents.begin(); while ( t < EPID_SIM_LENGTH ) { // Add some events to currentEvents while ( ( *eventIter ).time < nextTimeStep ) { Event thisEvent = *eventIter; t = thisEvent.time; executeEvent( thisEvent ); eventCtr++; currentEvents.erase( eventIter ); eventIter = currentEvents.begin(); } t = nextTimeStep; nextTimeStep += EPID_DELTA_T; } void Simulation::addEvent( double et, int eid, int hid, int s ) { assert( currentEvents.find( Event(et) ) == currentEvents.end() ); Event thisEvent( et, eid, hid, s ); currentEvents.insert( thisEvent ); }

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• how to differentiate between two threads

  - by mithun1538

  Hello everyone, I have the following code in my program: Thread getUsersist, getChatUsers; getUsersList = new Thread(this, "getOnlineUsers"); getUsersList.start(); getChatUsers = new Thread(this, "getChatUsers"); getChatUsers.start(); In run(), I wish to know which thread is using run(). If its "getOnlineUsers" i will do something, If it is "getChatUsers" I will do something else. So how do I know which thread is using run()?

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• Java Download Concurrent Data

  - by xger86x

  Hi, i'm developing an app which download map tiles around different places in a city. To do this, i have one thread for each place in which i select the tiles and create a thread to download each. Well, the question is how to avoid creating a thread for a tile that already exists in the thread pool. Should not just check if the file exists, since it is possible that the thread for that tile already exists (other place already need that tile) but the file has not been created- Any idea? Thanks

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• How come the Actionscript 3 ENTER_FRAME event is crazy nuts?

  - by nstory

  So, I've been toying around with Flash, browsing through the documentation, and all that, and noticed that the ENTER_FRAME event seems to defy my expectation of a deterministic universe. Take the following example: (new MovieClip()).addEventListener(Event.ENTER_FRAME, function(ev) {trace("Test");}); Notice this anonymous MovieClip is not added to the display hierarchy, and any reference to it is immediately lost. It will actually print "Test" once a frame until it is garbage collected. How insane is that? The behavior of this is actually determined by when the garbage collector feels like coming around in all its unpredictable insanity! Is there a better way to create intermittent failures? Seriously. My two theories are that either the DisplayObject class stores weak references to all its instances for the purpose of dispatching ENTER_FRAME events, or, and much wilder, the Flash player actually scans the heap each frame looking for ENTER_FRAME listeners to pull on. Can any hardened Actionscript developer clue me in on how this works? (And maybe a why - the - f**k they thought this was a good idea?)

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• Waiting until one event has happened before moving onto the next.

  - by jaasum

  I currently have a scrolling anchor animation that also adds an "active" class to the anchor clicked. I am trying to fit the below function into the works as well, so say someone clicks "anchor 1", "anchor 1" will get an active class and the window will scroll to that location. But, after that has happened say the user manually begins scrolling down the page, I want the active class to be removed. The problem I am running up against now is that the below function will happen when the scrolling animation from a clicked anchor is taking place. How can I disable this only when the window is being scrolled from a clicked anchor? $(window).scroll(function() { $('a[href^=#]').removeClass('active'); }); Here is the scrolling anchor script I am working with. /******* *** Anchor Slider by Cedric Dugas *** *** Http://www.position-absolute.com *** Never have an anchor jumping your content, slide it. Don't forget to put an id to your anchor ! You can use and modify this script for any project you want, but please leave this comment as credit. *****/ jQuery.fn.anchorAnimate = function(settings) { settings = jQuery.extend({ speed : 500 }, settings); return this.each(function(){ var caller = this $(caller).click(function (event) { event.preventDefault() var locationHref = window.location.href var elementClick = $(caller).attr("href") var destination = $(elementClick).offset().top; $("html:not(:animated),body:not(:animated)").animate({ scrollTop: destination}, settings.speed, 'easeOutCubic', function() { window.location.hash = elementClick }); return false; }) }) } And lastly, my jQuery // Scrolling Anchors $('[href^=#]').anchorAnimate(); // Active Class For Clicked Anchors var anchorscroll = $('a[href^=#]') anchorscroll.click(function(){ var anchorlocation = $(this).attr("href"); anchorscroll.removeClass('active'); $(this).addClass('active'); $('a[href='+anchorlocation+']').addClass('active'); });

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• Basic Android game loop having issues

  - by WillDaBeast509

  I've set up a very basic game loop that should draw a circle, run 100 times, then draw another. I also have a text field that should display how many times the loop has ran. However, the screen seems to not update. It displays a different value for the tick count (different each time the app is ran) and simply stays there. After exiting the app, I get an error saying "Unfortunately, MyApp has stopped." Here is the relevant code: DrawView public class DrawView extends SurfaceView implements SurfaceHolder.Callback { Paint p = new Paint(); MainThread thread; private int y=0; public DrawView(Context c) { super(c); thread = new MainThread(this, getHolder()); thread.running = true; getHolder().addCallback(this); setFocusable(true); } public void draw(Canvas c) { if(c==null) return; //super.onDraw(c); c.drawColor(Color.WHITE); p.setColor(Color.RED); p.setTextSize(32); p.setTypeface(Typeface.SANS_SERIF); c.drawCircle(getWidth()/2-100,getHeight()/2, 50, p); c.drawText("y = " + y, 50, 50, p); if(y>=100) { Log.i("DRAW", "drawing circle"); c.drawCircle(getWidth()/2+100,getHeight()/2, 50, p); } else y++; Log.i("INFO", "y = " + y); } @Override public boolean onTouchEvent(MotionEvent event) { return true; } public void onDraw(Canvas c){} public void surfaceCreated(SurfaceHolder p1) { thread.start(); } public void surfaceChanged(SurfaceHolder p1, int p2, int p3, int p4) { // TODO: Implement this method } public void surfaceDestroyed(SurfaceHolder p1) { thread.running = false; boolean retry = true; while (retry) { try { thread.join(); retry = false; } catch (InterruptedException e) { Log.i("EX", "cathing exception"); } } } } MainThread public class MainThread extends Thread { private DrawView page; private SurfaceHolder holder; public boolean running; public MainThread(DrawView p, SurfaceHolder h) { super(); page = p; holder = h; } @Override public void run() { while(running) { Canvas c = holder.lockCanvas(); page.draw(c); holder.unlockCanvasAndPost(c); } } } Here is an example log outupt: http://pastebin.com/tM9dUPuk It counts the number of ticks correctly and should draw the second circle, but the screen looks like its not updating. After closing the app, the log continues to run and keep outputting "y = 100 drawing circle" until it crashes and shows the error report. What is going on and how can I fix these two problems?

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• Actionscript / Flex: a question about handleAllEvents() method.

  - by Patrick

  Hi, in Adobe tutorials, they suggest to create a class to handle the events (see below the copy/pasted code, and link to page). I was wondering if I have to handle all events with the function handleAllEvents, using if statements to check if the target is the one I want, and the event is the one I want. i.e. if (event.type=="click") && (event.currentTarget == "myId") Should I have a list of ifs (for each target and each event type ?) thanks // events/MyStaticEventHandler.as package { // Empty package. import flash.events.Event; import mx.controls.Alert; public class MyStaticEventHandler { public function MyStaticEventHandler() { // Empty constructor. } public static function handleAllEvents(event:Event):void { Alert.show("Some event happened."); } } } Link (at the bottom): http://livedocs.adobe.com/flex/3/html/help.html?content=events_05.html

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• Why does my simple event handling example not work?

  - by njreed

  I am trying to make a simple event handler. (Note, I'm not trying to implement a full-blown publish/subscribe model; I'm just interested in why my example doesn't work as I think it should) var myObj = (function () { var private = "X"; function triggerEvent(eventName) { if (this[eventName]) { this[eventName](); } } // Setter / Getter function getProp() { return private; } function setProp(value) { private = value; triggerEvent("onPropChange"); } // Public API return { // Events "onPropChange": null, // Fires when prop value is changed // Methods "getProp": getProp, "setProp": setProp }; })(); // Now set event handler myObj.onPropChange = function () { alert("You changed the property!"); }; myObj.setProp("Z"); // --> Nothing happens. Wrong // Why doesn't my alert show? I set the onPropChange property of my object to a simpler handler function but it is not being fired. I have debugged this and it seems that in triggerEvent the variable this is referencing the global window object. I thought it should reference myObj (which is what I need). Can someone explain the error in my thinking and how I correct this? Help much appreciated. jsFiddle here

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• Can I avoid a threaded UDP socket in Pyton dropping data?

  - by 666craig

  First off, I'm new to Python and learning on the job, so be gentle! I'm trying to write a threaded Python app for Windows that reads data from a UDP socket (thread-1), writes it to file (thread-2), and displays the live data (thread-3) to a widget (gtk.Image using a gtk.gdk.pixbuf). I'm using queues for communicating data between threads. My problem is that if I start only threads 1 and 3 (so skip the file writing for now), it seems that I lose some data after the first few samples. After this drop it looks fine. Even by letting thread 1 complete before running thread 3, this apparent drop is still there. Apologies for the length of code snippet (I've removed the thread that writes to file), but I felt removing code would just prompt questions. Hope someone can shed some light :-) import socket import threading import Queue import numpy import gtk gtk.gdk.threads_init() import gtk.glade import pygtk class readFromUDPSocket(threading.Thread): def __init__(self, socketUDP, readDataQueue, packetSize, numScans): threading.Thread.__init__(self) self.socketUDP = socketUDP self.readDataQueue = readDataQueue self.packetSize = packetSize self.numScans = numScans def run(self): for scan in range(1, self.numScans + 1): buffer = self.socketUDP.recv(self.packetSize) self.readDataQueue.put(buffer) self.socketUDP.close() print 'myServer finished!' class displayWithGTK(threading.Thread): def __init__(self, displayDataQueue, image, viewArea): threading.Thread.__init__(self) self.displayDataQueue = displayDataQueue self.image = image self.viewWidth = viewArea[0] self.viewHeight = viewArea[1] self.displayData = numpy.zeros((self.viewHeight, self.viewWidth, 3), dtype=numpy.uint16) def run(self): scan = 0 try: while True: if not scan % self.viewWidth: scan = 0 buffer = self.displayDataQueue.get(timeout=0.1) self.displayData[:, scan, 0] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 1] = numpy.fromstring(buffer, dtype=numpy.uint16) self.displayData[:, scan, 2] = numpy.fromstring(buffer, dtype=numpy.uint16) gtk.gdk.threads_enter() self.myPixbuf = gtk.gdk.pixbuf_new_from_data(self.displayData.tostring(), gtk.gdk.COLORSPACE_RGB, False, 8, self.viewWidth, self.viewHeight, self.viewWidth * 3) self.image.set_from_pixbuf(self.myPixbuf) self.image.show() gtk.gdk.threads_leave() scan += 1 except Queue.Empty: print 'myDisplay finished!' pass def quitGUI(obj): print 'Currently active threads: %s' % threading.enumerate() gtk.main_quit() if __name__ == '__main__': # Create socket (IPv4 protocol, datagram (UDP)) and bind to address socketUDP = socket.socket(socket.AF_INET, socket.SOCK_DGRAM) host = '192.168.1.5' port = 1024 socketUDP.bind((host, port)) # Data parameters samplesPerScan = 256 packetsPerSecond = 1200 packetSize = 512 duration = 1 # For now, set a fixed duration to log data numScans = int(packetsPerSecond * duration) # Create array to store data data = numpy.zeros((samplesPerScan, numScans), dtype=numpy.uint16) # Create queue for displaying from readDataQueue = Queue.Queue(numScans) # Build GUI from Glade XML file builder = gtk.Builder() builder.add_from_file('GroundVue.glade') window = builder.get_object('mainwindow') window.connect('destroy', quitGUI) view = builder.get_object('viewport') image = gtk.Image() view.add(image) viewArea = (1200, samplesPerScan) # Instantiate & start threads myServer = readFromUDPSocket(socketUDP, readDataQueue, packetSize, numScans) myDisplay = displayWithGTK(readDataQueue, image, viewArea) myServer.start() myDisplay.start() gtk.gdk.threads_enter() gtk.main() gtk.gdk.threads_leave() print 'gtk.main finished!'

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• Xml schema, how to make sure one element exists with a specific attribute value

  - by pexxxy

  How do I enforce the existing of an element with a specific attribute value in the XML? For example: <events> <event type="system" desc="this is a system event"/> <event type="bla1" desc="this is bla1 event"/> <event type="bla2" desc="this is bla2 event"/> </events> I need a rule to make sure the event element with type attribute = 'system' exists (once). All other event elements are optional;

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• IndyTechFest Recap

  - by Johnm

  The sun had yet to raise above the horizon on Saturday, May 22nd and I was traveling toward the location of the 2010 IndyTechFest. In my freshly awaken, and pre-coffee, state I reflected on the months that preceded this day and how quickly they slipped away. The big day had finally come and the morning dew glistened with a unique brightness that morning. What is this all about? For those who are unfamiliar with IndyTechFest, it is a regional conference held in Indianapolis and hosted by the Indianapolis .NET Developers Association (IndyNDA) and the Indianapolis Professional Association for SQL Server (IndyPASS).  The event presents multiple tracks and sessions covering subjects such as Business Intelligence,  Database Administration, .NET Development, SharePoint Development, Windows Mobile Development as well as non-Microsoft topics such as Lean and MongoDB. This year's event was the third hosting of IndyTechFest. No man is an island No event such as IndyTechFest is executed by a single person. My fellow co-founders, with their highly complementary skill sets and philanthropy make the process very enjoyable. Our amazing volunteers and their aid were indispensible. The generous financial support of our sponsors that made the event and fabulous prizes possible. The spectacular line up of speakers who came from near and far to donate their time and knowledge. Our beloved attendees who sacrificed the first sunny Saturday in weeks to expand their skill sets and network with their peers. We are deeply appreciative. Challenges in preparation With the preparation of any event comes challenges. It is these challenges that makes the process of planning an event so interesting. This year's largest challenge was the location of the event. In the past two years IndyTechFest was held at the Gene B. Glick Junior Achievement Center in Indianapolis. This facility has been the hub of the Indy technical community for many years. As the big day drew near, the facility's availability came into question due to some recent changes that had occurred with those who operated the facility. We began our search for an alternative option. Thankfully, the Marriott Indianapolis East was available, was very spacious and willing to work within the range of our budget. Within days of our event, the decision to move proved to be wise since the prior location had begun renovations to the interior. Whew! Always trust your gut. Every day it's getting better At the ending of each year, we huddle together, review the evaluations and identify an area in which the event could improve. This year's big opportunity for improvement resided in the prize give-away portion at the end of the day. In the 2008 event, admittedly, this portion was rather chaotic, rushed and disorganized. This year, we broke the drawing into two sections, of which each attendee received two tickets. The first ticket was a drawing for the mountain of books that were given away. The second ticket was a drawing for the big prizes, the 2 Xboxes, 3 laptops and iPad. We peppered the ticket drawings with gift card raffles and tossing t-shirts into the audience. If at first you don't succeed, try and try again Each year of IndyTechFest, we have offered a means for ad-hoc sessions or discussion groups to pop-up. To our disappointment it was something that never quite took off. We have always believed that this unique type of session was valuable and wanted to figure out a way to make it work for this year. A special thanks to Alan Stevens, who took on and facilitated the "open space" track and made it an official success. Share with your tweety When the attendee badges were designed we decided to place an emphasis on the attendee's Twitter account as well as the events hash-tag (#IndyTechFest) to encourage some real-time buzz during the day. At the host table we displayed a Twitter feed for all to enjoy. It was quite successful and encouraging use of social media. My badge was missing my Twitter account since it was recently changed. For those who care to follow my rather sparse tweets, my address is @johnnydata. Man, this is one long blog post! All in all it was a very successful event. It is always great to see new faces and meet old friends. The planning for the 2011 IndyTechFest will kick off very soon. We have more capacity for future growth and a truck full of great ideas. Stay tuned!

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• What developer conferences are you going to this year?

  - by mbcrump

  This short list is what I consider to be the “cream-of-the-crop” in developer conferences. This is also a list of the conferences that I plan on attending in 2011. If you feel your conference is just as good, then shoot me an email at [michael[at]michaelcrump[dot]net, and if possible I will check it out.   In-Person Event Las Vegas on April 18th-22nd, 2011 Redmond on October 17th-21st, 2011 Orlando on December 5th-9th, 2011 Visual Studio Live – I attended this event in November of last year and blogged about my experience. I am also planning on going back to the Orlando session in December of this year. So what did I like the most about this event? Being able to interact one-on-one with a majority of the speakers. If you read my blog post then you will see a list of the speakers that I met up with. I also made a lot of great connections with other professional developers all over the world. They are having an event in Las Vegas on April 18th-22nd. I noticed at this event that they have added a new track on mobile. Being a big fan of mobile, I feel that this is a great move. They also have a great selection for Silverlight Developers including Billy Hollis and Rocky Lhotka. For the full lineup of conference tracks, sessions and speakers visit http://bit.ly/VSLiveTrks. If you are interested in this then you can register here by February 16th. I must add that you can save $300 bucks by getting the early-bird special.   Virtual Conference SSWUG (DBTechCon) - holds the largest virtual conference in the information technology industry. It is also special to me because they selected a majority of my Silverlight content for the April conference. No traveling fees and all of the sessions are recorded so you can watch them on-demand for $189 bucks (early-bird special). For the entire speaker list then click here. The session list has also been published. If you are interested in this then you can register here.   In-Person Event Knoxville, TN on June 3rd/4th 2011. Codestock.org – If you live in the South then you have heard of CodeStock. To my knowledge, they have only had 3 events so far and they were a huge success. It was such a success that after the last event, everyone was telling me how good it was and how much they enjoyed it. They currently have a call for speakers going on right now, so if you have sessions then be sure to submit yours. So, what makes them stand out? Well for starters Michael Neal (organizer) developed an open API so conference attendees could build their own apps for the sessions. They also encouraged their speakers to go to other sessions instead of stay in a “speaker-room”. Another cool feature is that they are uploading videos from the conference so everyone can benefit. They are currently looking for sponsorship, so help out if you can.   In-Person Event Redmond, WA on October 28/29 2011 *NOT 100% SURE AT THIS POINT* PDC 11 – OK, so the logo should be pdc11 but its not out yet. This event is located on Microsoft’s campus in Redmond, WA. It is probably one of the most well known conferences for developers to attend. One of the big perks from this event is that you typically come away with free stuff. In 2010 they gave away Windows 7 Phones. I remember years earlier they gave away laptops. This of course isn’t the only reason to go, you may get to tour the Microsoft campus. Since pdc is a huge event, you can view all the events for free. Mike Taulty created a nice Silverlight application that consumes the OData feed. You can download it here. If everything goes as planned, I will be at all of these events. If you plan on going then send me a tweet and we will do lunch or dinner. I love meeting new developers and talking .net.  Subscribe to my feed

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• "ID 046d:c50e Logitech, Inc. Cordless Mouse Receiver" wheel-click is wrong

  - by sputnick

  I use this mouse under archlinux x86_64 with 3.2.8-1-ARCH kernel. I have some problems to select and then paste with the wheel-click in some applications like konversation, not in a terminal nor an editor. I don't know if it's a hardware problem or a software one. $ lsusb -v Bus 002 Device 110: ID 046d:c50e Logitech, Inc. Cordless Mouse Receiver Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 1.10 bDeviceClass 0 (Defined at Interface level) bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 8 idVendor 0x046d Logitech, Inc. idProduct 0xc50e Cordless Mouse Receiver bcdDevice 25.10 iManufacturer 1 Logitech iProduct 2 USB RECEIVER iSerial 0 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 34 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xa0 (Bus Powered) Remote Wakeup MaxPower 70mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 1 bInterfaceClass 3 Human Interface Device bInterfaceSubClass 1 Boot Interface Subclass bInterfaceProtocol 2 Mouse iInterface 0 HID Device Descriptor: bLength 9 bDescriptorType 33 bcdHID 1.11 bCountryCode 0 Not supported bNumDescriptors 1 bDescriptorType 34 Report wDescriptorLength 95 Report Descriptors: ** UNAVAILABLE ** Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x81 EP 1 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0008 1x 8 bytes bInterval 10 Device Status: 0x0000 (Bus Powered) When I see what's happens in xev, the output is different compared to another mouse My buggy Logitech mouse : ButtonPress event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170350700, (48,52), root:(1491,75), state 0x10, button 11, same_screen YES EnterNotify event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x0, time 170350700, (48,52), root:(1491,75), mode NotifyGrab, detail NotifyInferior, same_screen YES, focus YES, state 16 KeymapNotify event, serial 40, synthetic NO, window 0x0, keys: 90 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ButtonPress event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170350716, (48,52), root:(1491,75), state 0x10, button 6, same_screen YES ButtonRelease event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170350716, (48,52), root:(1491,75), state 0x10, button 6, same_screen YES ButtonRelease event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170350988, (48,52), root:(1491,75), state 0x10, button 11, same_screen YES LeaveNotify event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x0, time 170350988, (48,52), root:(1491,75), mode NotifyUngrab, detail NotifyInferior, same_screen YES, focus YES, state 16 a working mouse (dell) : ButtonPress event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170245131, (46,32), root:(1489,55), state 0x10, button 2, same_screen YES EnterNotify event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x0, time 170245131, (46,32), root:(1489,55), mode NotifyGrab, detail NotifyInferior, same_screen YES, focus YES, state 528 KeymapNotify event, serial 40, synthetic NO, window 0x0, keys: 90 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 ButtonRelease event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x4400002, time 170245411, (46,32), root:(1489,55), state 0x210, button 2, same_screen YES LeaveNotify event, serial 40, synthetic NO, window 0x4400001, root 0x15a, subw 0x0, time 170245411, (46,32), root:(1489,55), mode NotifyUngrab, detail NotifyInferior, same_screen YES, focus YES, state 16 A demo of the problem when I use konversation (IRC) : http://www.youtube.com/watch?v=lhmr92M7NCc I tried to modify the button map with xmodmap like this with no success (one at a time) : xmodmap -e "pointer = 1 0 3" xmodmap -e "pointer = 1 1 3" xmodmap -e "pointer = 1 2 3" xmodmap -e "pointer = 1 3 3" xmodmap -e "pointer = 1 4 3" xmodmap -e "pointer = 1 5 3" xmodmap -e "pointer = 1 6 3" xmodmap -e "pointer = 1 7 3" xmodmap -e "pointer = 1 8 3" xmodmap -e "pointer = 1 9 3" xmodmap -e "pointer = 1 10 3" xmodmap -e "pointer = 1 11 3" xmodmap -e "pointer = 1 12 3" xmodmap -e "pointer = 1 13 3" xmodmap -e "pointer = 1 14 3" xmodmap -e "pointer = 1 15 3" xmodmap -e "pointer = 1 16 3" xmodmap -e "pointer = 1 17 3" xmodmap -e "pointer = 1 18 3" xmodmap -e "pointer = 1 19 3" xmodmap -e "pointer = 1 20 3" xmodmap -e "pointer = 1 21 3" xmodmap -e "pointer = 1 22 3" xmodmap -e "pointer = 1 23 3" xmodmap -e "pointer = 1 24 3" xmodmap -e "pointer = 1 25 3" Any clue ? I would like to avoid buying a new mouse just for a paste problem.

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• Elusive race condition in Java

  - by nasufara

  I am creating a graphing calculator. In an attempt to squeeze some more performance out of it, I added some multithreaded to the line calculator. Essentially what my current implementation does is construct a thread-safe Queue of X values, then start however many threads it needs, each one calculating a point on the line using the queue to get its values, and then ordering the points using a HashMap when the calculations are done. This implementation works great, and that's not where my race condition is (merely some background info). In examining the performance results from this, I found that the HashMap is a performance bottleneck, since I do that synchronously on one thread. So I figured that ordering each point as its calculated would work best. I tried a PriorityQueue, but that was slower than the HashMap. I ended up creating an algorithm that essentially works like this: I construct a list of X values to calculate, like in my current algorithm. I then copy that list of values into another class, unimaginatively and temporarily named BlockingList, which is responsible for ordering the points as they are calculated. BlockingList contains a put() method, which takes in two BigDecimals as parameters, the first the X value, the second the calculated Y value. put() will only accept a value if the X value is the next one on the list to be accepted in the list of X values, and will block until another thread gives it the next excepted value. For example, since that can be confusing, say I have two threads, Thread-1 and Thread-2. Thread-2 gets the X value 10.0 from the values queue, and Thread-1 gets 9.0. However, Thread-1 completes its calculations first, and calls put() before Thread-2 does. Because BlockingList is expecting to get 10.0 first, and not 9.0, it will block on Thread-1 until Thread-2 finishes and calls put(). Once Thread-2 gives BlockingList 10.0, it notify()s all waiting threads, and expects 9.0 next. This continues until BlockingList gets all of its expected values. (I apologise if that was hard to follow, if you need more clarification, just ask.) As expected by the question title, there is a race condition in here. If I run it without any System.out.printlns, it will sometimes lock because of conflicting wait() and notifyAll()s, but if I put a println in, it will run great. A small implementation of this is included below, and exhibits the same behavior: import java.math.BigDecimal; import java.util.concurrent.ConcurrentLinkedQueue; public class Example { public static void main(String[] args) throws InterruptedException { // Various scaling values, determined based on the graph size // in the real implementation BigDecimal xMax = new BigDecimal(10); BigDecimal xStep = new BigDecimal(0.05); // Construct the values list, from -10 to 10 final ConcurrentLinkedQueue<BigDecimal> values = new ConcurrentLinkedQueue<BigDecimal>(); for (BigDecimal i = new BigDecimal(-10); i.compareTo(xMax) <= 0; i = i.add(xStep)) { values.add(i); } // Contains the calculated values final BlockingList list = new BlockingList(values); for (int i = 0; i < 4; i++) { new Thread() { public void run() { BigDecimal x; // Keep looping until there are no more values while ((x = values.poll()) != null) { PointPair pair = new PointPair(); pair.realX = x; try { list.put(pair); } catch (Exception ex) { ex.printStackTrace(); } } } }.start(); } } private static class PointPair { public BigDecimal realX; } private static class BlockingList { private final ConcurrentLinkedQueue<BigDecimal> _values; private final ConcurrentLinkedQueue<PointPair> _list = new ConcurrentLinkedQueue<PointPair>(); public BlockingList(ConcurrentLinkedQueue<BigDecimal> expectedValues) throws InterruptedException { // Copy the values into a new queue BigDecimal[] arr = expectedValues.toArray(new BigDecimal[0]); _values = new ConcurrentLinkedQueue<BigDecimal>(); for (BigDecimal dec : arr) { _values.add(dec); } } public void put(PointPair item) throws InterruptedException { while (item.realX.compareTo(_values.peek()) != 0) { synchronized (this) { // Block until someone enters the next desired value wait(); } } _list.add(item); _values.poll(); synchronized (this) { notifyAll(); } } } } My question is can anybody help me find the threading error? Thanks!

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• Yet another C# Deadlock Debugging Question

  - by Roo

  Hi All, I have a multi-threaded application build in C# using VS2010 Professional. It's quite a large application and we've experienced the classing GUI cross-threading and deadlock issues before, but in the past month we've noticed the appears to lock up when left idle for around 20-30 minutes. The application is irresponsive and although it will repaint itself when other windows are dragged in front of the application and over it, the GUI still appears to be locked... interstingly (unlike if the GUI thread is being used for a considerable amount of time) the Close, Maximise and minimise buttons are also irresponsive and when clicked the little (Not Responding...) text is not displayed in the title of the application i.e. Windows still seems to think it's running fine. If I break/pause the application using the debugger, and view the threads that are running. There are 3 threads of our managed code that are running, and a few other worker threads whom the source code cannot be displayed for. The 3 threads that run are: The main/GUI thread A thread that loops indefinitely A thread that loops indefinitely If I step into threads 2 and 3, they appear to be looping correctly. They do not share locks (even with the main GUI thread) and they are not using the GUI thread at all. When stepping into the main/GUI thread however, it's broken on Application.Run... This problem screams deadlock to me, but what I don't understand is if it's deadlock, why can't I see the line of code the main/GUI thread is hanging on? Any help will be greatly appreciated! Let me know if you need more information... Cheers, Roo -----------------------------------------------------SOLUTION-------------------------------------------------- Okay, so the problem is now solved. Thanks to everyone for their suggestions! Much appreciated! I've marked the answer that solved my initial problem of determining where on the main/UI thread the application hangs (I handn't turned off the "Enable Just My Code" option). The overall issue I was experiencing was indeed Deadlock, however. After obtaining the call-stack and popping the top half of it into Google I came across this which explains exactly what I was experiencing... http://timl.net/ This references a lovely guide to debugging the issue... http://www.aaronlerch.com/blog/2008/12/15/debugging-ui/ This identified a control I was constructing off the GUI thread. I did know this, however, and was marshalling calls correctly, but what I didn't realise was that behind the scenes this Control was subscribing to an event or set of events that are triggered when e.g. a Windows session is unlocked or the screensaver exits. These calls are always made on the main/UI thread and were blocking when it saw the call was made on the incorrect thread. Kim explains in more detail here... http://krgreenlee.blogspot.com/2007/09/onuserpreferencechanged-hang.html In the end I found an alternative solution which did not require this Control off the main/UI thread. That appears to have solved the problem and the application no longer hangs. I hope this helps anyone who's confronted by a similar problem. Thanks again to everyone on here who helped! (and indirectly, the delightful bloggers I've referenced above!) Roo -----------------------------------------------------SOLUTION II-------------------------------------------------- Aren't threading issues delightful...you think you've solved it, and a month down the line it pops back up again. I still believe the solution above resolved an issue that would cause simillar behaviour, but we encountered the problem again. As we spent a while debugging this, I thought I'd update this question with our (hopefully) final solution: The problem appears to have been a bug in the Infragistics components in the WinForms 2010.1 release (no hot fixes). We had been running from around the time the freeze issue appeared (but had also added a bunch of other stuff too). After upgrading to WinForms 2010.3, we've yet to reproduce the issue (deja vu). See my question here for a bit more information: 'http://stackoverflow.com/questions/4077822/net-4-0-and-the-dreaded-onuserpreferencechanged-hang'. Hans has given a nice summary of the general issue. I hope this adds a little to the suggestions/information surrounding the nutorious OnUserPreferenceChanged Hang (or whatever you'd like to call it). Cheers, Roo

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• Handling file upload in a non-blocking manner

  - by Kaliyug Antagonist

  The background thread is here Just to make objective clear - the user will upload a large file and must be redirected immediately to another page for proceeding different operations. But the file being large, will take time to be read from the controller's InputStream. So I unwillingly decided to fork a new Thread to handle this I/O. The code is as follows : The controller servlet /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse * response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub System.out.println("In Controller.doPost(...)"); TempModel tempModel = new TempModel(); tempModel.uploadSegYFile(request, response); System.out.println("Forwarding to Accepted.jsp"); /*try { Thread.sleep(1000 * 60); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); }*/ request.getRequestDispatcher("/jsp/Accepted.jsp").forward(request, response); } The model class package com.model; import java.io.IOException; import java.util.concurrent.ExecutionException; import java.util.concurrent.Future; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.utils.ProcessUtils; public class TempModel { public void uploadSegYFile(HttpServletRequest request, HttpServletResponse response) { // TODO Auto-generated method stub System.out.println("In TempModel.uploadSegYFile(...)"); /* * Trigger the upload/processing code in a thread, return immediately * and notify when the thread completes */ try { FileUploaderRunnable fileUploadRunnable = new FileUploaderRunnable( request.getInputStream()); /* * Future<FileUploaderRunnable> future = ProcessUtils.submitTask( * fileUploadRunnable, fileUploadRunnable); * * FileUploaderRunnable processed = future.get(); * * System.out.println("Is file uploaded : " + * processed.isFileUploaded()); */ Thread uploadThread = new Thread(fileUploadRunnable); uploadThread.start(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } /* * catch (InterruptedException e) { // TODO Auto-generated catch block * e.printStackTrace(); } catch (ExecutionException e) { // TODO * Auto-generated catch block e.printStackTrace(); } */ System.out.println("Returning from TempModel.uploadSegYFile(...)"); } } The Runnable package com.model; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.nio.ByteBuffer; import java.nio.channels.Channels; import java.nio.channels.ReadableByteChannel; public class FileUploaderRunnable implements Runnable { private boolean isFileUploaded = false; private InputStream inputStream = null; public FileUploaderRunnable(InputStream inputStream) { // TODO Auto-generated constructor stub this.inputStream = inputStream; } public void run() { // TODO Auto-generated method stub /* Read from InputStream. If success, set isFileUploaded = true */ System.out.println("Starting upload in a thread"); File outputFile = new File("D:/06c01_output.seg");/* * This will be changed * later */ FileOutputStream fos; ReadableByteChannel readable = Channels.newChannel(inputStream); ByteBuffer buffer = ByteBuffer.allocate(1000000); try { fos = new FileOutputStream(outputFile); while (readable.read(buffer) != -1) { fos.write(buffer.array()); buffer.clear(); } fos.flush(); fos.close(); readable.close(); } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.println("File upload thread completed"); } public boolean isFileUploaded() { return isFileUploaded; } } My queries/doubts : Spawning threads manually from the Servlet makes sense to me logically but scares me coding wise - the container isn't aware of these threads after all(I think so!) The current code is giving an Exception which is quite obvious - the stream is inaccessible as the doPost(...) method returns before the run() method completes : In Controller.doPost(...) In TempModel.uploadSegYFile(...) Returning from TempModel.uploadSegYFile(...) Forwarding to Accepted.jsp Starting upload in a thread Exception in thread "Thread-4" java.lang.NullPointerException at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:512) at org.apache.coyote.http11.InternalInputBuffer.fill(InternalInputBuffer.java:497) at org.apache.coyote.http11.InternalInputBuffer$InputStreamInputBuffer.doRead(InternalInputBuffer.java:559) at org.apache.coyote.http11.AbstractInputBuffer.doRead(AbstractInputBuffer.java:324) at org.apache.coyote.Request.doRead(Request.java:422) at org.apache.catalina.connector.InputBuffer.realReadBytes(InputBuffer.java:287) at org.apache.tomcat.util.buf.ByteChunk.substract(ByteChunk.java:407) at org.apache.catalina.connector.InputBuffer.read(InputBuffer.java:310) at org.apache.catalina.connector.CoyoteInputStream.read(CoyoteInputStream.java:202) at java.nio.channels.Channels$ReadableByteChannelImpl.read(Unknown Source) at com.model.FileUploaderRunnable.run(FileUploaderRunnable.java:39) at java.lang.Thread.run(Unknown Source) Keeping in mind the point 1., does the use of Executor framework help me in anyway ? package com.utils; import java.util.concurrent.Future; import java.util.concurrent.ScheduledThreadPoolExecutor; public final class ProcessUtils { /* Ensure that no more than 2 uploads,processing req. are allowed */ private static final ScheduledThreadPoolExecutor threadPoolExec = new ScheduledThreadPoolExecutor( 2); public static <T> Future<T> submitTask(Runnable task, T result) { return threadPoolExec.submit(task, result); } } So how should I ensure that the user doesn't block and the stream remains accessible so that the (uploaded)file can be read from it?

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• Talend Enterprise Data Integration overperforms on Oracle SPARC T4

  - by Amir Javanshir

  The SPARC T microprocessor, released in 2005 by Sun Microsystems, and now continued at Oracle, has a good track record in parallel execution and multi-threaded performance. However it was less suited for pure single-threaded workloads. The new SPARC T4 processor is now filling that gap by offering a 5x better single-thread performance over previous generations. Following our long-term relationship with Talend, a fast growing ISV positioned by Gartner in the “Visionaries” quadrant of the “Magic Quadrant for Data Integration Tools”, we decided to test some of their integration components with the T4 chip, more precisely on a T4-1 system, in order to verify first hand if this new processor stands up to its promises. Several tests were performed, mainly focused on: Single-thread performance of the new SPARC T4 processor compared to an older SPARC T2+ processor Overall throughput of the SPARC T4-1 server using multiple threads The tests consisted in reading large amounts of data --ten's of gigabytes--, processing and writing them back to a file or an Oracle 11gR2 database table. They are CPU, memory and IO bound tests. Given the main focus of this project --CPU performance--, bottlenecks were removed as much as possible on the memory and IO sub-systems. When possible, the data to process was put into the ZFS filesystem cache, for instance. Also, two external storage devices were directly attached to the servers under test, each one divided in two ZFS pools for read and write operations. Multi-thread: Testing throughput on the Oracle T4-1 The tests were performed with different number of simultaneous threads (1, 2, 4, 8, 12, 16, 32, 48 and 64) and using different storage devices: Flash, Fibre Channel storage, two stripped internal disks and one single internal disk. All storage devices used ZFS as filesystem and volume management. Each thread read a dedicated 1GB-large file containing 12.5M lines with the following structure: customerID;FirstName;LastName;StreetAddress;City;State;Zip;Cust_Status;Since_DT;Status_DT 1;Ronald;Reagan;South Highway;Santa Fe;Montana;98756;A;04-06-2006;09-08-2008 2;Theodore;Roosevelt;Timberlane Drive;Columbus;Louisiana;75677;A;10-05-2009;27-05-2008 3;Andrew;Madison;S Rustle St;Santa Fe;Arkansas;75677;A;29-04-2005;09-02-2008 4;Dwight;Adams;South Roosevelt Drive;Baton Rouge;Vermont;75677;A;15-02-2004;26-01-2007 […] The following graphs present the results of our tests: Unsurprisingly up to 16 threads, all files fit in the ZFS cache a.k.a L2ARC : once the cache is hot there is no performance difference depending on the underlying storage. From 16 threads upwards however, it is clear that IO becomes a bottleneck, having a good IO subsystem is thus key. Single-disk performance collapses whereas the Sun F5100 and ST6180 arrays allow the T4-1 to scale quite seamlessly. From 32 to 64 threads, the performance is almost constant with just a slow decline. For the database load tests, only the best IO configuration --using external storage devices-- were used, hosting the Oracle table spaces and redo log files. Using the Sun Storage F5100 array allows the T4-1 server to scale up to 48 parallel JVM processes before saturating the CPU. The final result is a staggering 646K lines per second insertion in an Oracle table using 48 parallel threads. Single-thread: Testing the single thread performance Seven different tests were performed on both servers. Given the fact that only one thread, thus one file was read, no IO bottleneck was involved, all data being served from the ZFS cache. Read File ? Filter ? Write File: Read file, filter data, write the filtered data in a new file. The filter is set on the “Status” column: only lines with status set to “A” are selected. This limits each output file to about 500 MB. Read File ? Load Database Table: Read file, insert into a single Oracle table. Average: Read file, compute the average of a numeric column, write the result in a new file. Division & Square Root: Read file, perform a division and square root on a numeric column, write the result data in a new file. Oracle DB Dump: Dump the content of an Oracle table (12.5M rows) into a CSV file. Transform: Read file, transform, write the result data in a new file. The transformations applied are: set the address column to upper case and add an extra column at the end, which is the concatenation of two columns. Sort: Read file, sort a numeric and alpha numeric column, write the result data in a new file. The following table and graph present the final results of the tests: Throughput unit is thousand lines per second processed (K lines/second). Improvement is the % of improvement between the T5140 and T4-1. Test T4-1 (Time s.) T5140 (Time s.) Improvement T4-1 (Throughput) T5140 (Throughput) Read/Filter/Write 125 806 645% 100 16 Read/Load Database 195 1111 570% 64 11 Average 96 557 580% 130 22 Division & Square Root 161 1054 655% 78 12 Oracle DB Dump 164 945 576% 76 13 Transform 159 1124 707% 79 11 Sort 251 1336 532% 50 9 The improvement of single-thread performance is quite dramatic: depending on the tests, the T4 is between 5.4 to 7 times faster than the T2+. It seems clear that the SPARC T4 processor has gone a long way filling the gap in single-thread performance, without sacrifying the multi-threaded capability as it still shows a very impressive scaling on heavy-duty multi-threaded jobs. Finally, as always at Oracle ISV Engineering, we are happy to help our ISV partners test their own applications on our platforms, so don't hesitate to contact us and let's see what the SPARC T4-based systems can do for your application! "As describe in this benchmark, Talend Enterprise Data Integration has overperformed on T4. I was generally happy to see that the T4 gave scaling opportunities for many scenarios like complex aggregations. Row by row insertion in Oracle DB is faster with more than 650,000 rows per seconds without using any bulk Oracle capabilities !" Cedric Carbone, Talend CTO.

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• .NET 4: &ldquo;Slim&rdquo;-style performance boost!

  - by Vitus

  RTM version of .NET 4 and Visual Studio 2010 is available, and now we can do some test with it. Parallel Extensions is one of the most valuable part of .NET 4.0. It’s a set of good tools for easily consuming multicore hardware power. And it also contains some “upgraded” sync primitives – Slim-version. For example, it include updated variant of widely known ManualResetEvent. For people, who don’t know about it: you can sync concurrency execution of some pieces of code with this sync primitive. Instance of ManualResetEvent can be in 2 states: signaled and non-signaled. Transition between it possible by Set() and Reset() methods call. Some shortly explanation: Thread 1 Thread 2 Time mre.Reset(); mre.WaitOne(); //code execution 0 //wating //code execution 1 //wating //code execution 2 //wating //code execution 3 //wating mre.Set(); 4 //code execution //… 5 Upgraded version of this primitive is ManualResetEventSlim. The idea in decreasing performance cost in case, when only 1 thread use it. Main concept in the “hybrid sync schema”, which can be done as following:   internal sealed class SimpleHybridLock : IDisposable { private Int32 m_waiters = 0; private AutoResetEvent m_waiterLock = new AutoResetEvent(false);   public void Enter() { if (Interlocked.Increment(ref m_waiters) == 1) return; m_waiterLock.WaitOne(); }   public void Leave() { if (Interlocked.Decrement(ref m_waiters) == 0) return; m_waiterLock.Set(); }   public void Dispose() { m_waiterLock.Dispose(); } } It’s a sample from Jeffry Richter’s book “CLR via C#”, 3rd edition. Primitive SimpleHybridLock have two public methods: Enter() and Leave(). You can put your concurrency-critical code between calls of these methods, and it would executed in only one thread at the moment. Code is really simple: first thread, called Enter(), increase counter. Second thread also increase counter, and suspend while m_waiterLock is not signaled. So, if we don’t have concurrent access to our lock, “heavy” methods WaitOne() and Set() will not called. It’s can give some performance bonus. ManualResetEvent use the similar idea. Of course, it have more “smart” technics inside, like a checking of recursive calls, and so on. I want to know a real difference between classic ManualResetEvent realization, and new –Slim. I wrote a simple “benchmark”: class Program { static void Main(string[] args) { ManualResetEventSlim mres = new ManualResetEventSlim(false); ManualResetEventSlim mres2 = new ManualResetEventSlim(false);   ManualResetEvent mre = new ManualResetEvent(false);   long total = 0; int COUNT = 50;   for (int i = 0; i < COUNT; i++) { mres2.Reset(); Stopwatch sw = Stopwatch.StartNew();   ThreadPool.QueueUserWorkItem((obj) => { //Method(mres, true); Method2(mre, true); mres2.Set(); }); //Method(mres, false); Method2(mre, false);   mres2.Wait(); sw.Stop();   Console.WriteLine("Pass {0}: {1} ms", i, sw.ElapsedMilliseconds); total += sw.ElapsedMilliseconds; }   Console.WriteLine(); Console.WriteLine("==============================="); Console.WriteLine("Done in average=" + total / (double)COUNT); Console.ReadLine(); }   private static void Method(ManualResetEventSlim mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } }   private static void Method2(ManualResetEvent mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } } } I use 2 concurrent thread (the main thread and one from thread pool) for setting and resetting ManualResetEvents, and try to run test COUNT times, and calculate average execution time. Here is the results (I get it on my dual core notebook with T7250 CPU and Windows 7 x64): ManualResetEvent ManualResetEventSlim Difference is obvious and serious – in 10 times! So, I think preferable way is using ManualResetEventSlim, because not always on calling Set() and Reset() will be called “heavy” methods for working with Windows kernel-mode objects. It’s a small and nice improvement! ;)

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