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  • Air XmlHttpRequest time out if remote server is offline?

    - by Seth
    I'm writing an AIR application that communicates with a server via XmlHttpRequest. The problem that I'm having is that if the server is unreachable, my asynchronous XmlHttpRequest never seems to fail. My onreadystatechange handler detects the OPENED state, but nothing else. Is there a way to make the XmlHttpRequest time out? Do I have to do something silly like using setTimeout() to wait a while then abort() if the connection isn't established? Edit: Found this, but in my testing, wrapping my xmlhttprequest.send() in a try/catch block or setting a value on xmlhttprequest.timeout (or TimeOut or timeOut) doesn't have any affect.

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  • Calling C function from DTrace scripts

    - by dmeister
    DTrace is impressive, powerful tracing system originally from Solaris, but it is ported to FreeBSD and Mac OSX. DTrace uses a high-level language called D not unlike AWK or C. Here is an example: io:::start /pid == $1/ { printf("file %s offset %d size %d block %llu\n", args[2]->fi_pathname, args[2]->fi_offset, args[0]->b_bcount, args[0]->b_blkno); } Using the command line sudo dtrace -q -s <name>.d <pid> all IOs originated from that process are logged. My question is if and how it is possible to call custom C functions from a DTrace script to do advanced operations with that tracing data during the tracing itself.

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  • Throwing Exception in CTOR and Smart Pointers

    - by David Relihan
    Is it OK to have the following code in my constructor to load an XML document into a member variable - throwing to caller if there are any problems: MSXML2::IXMLDOMDocumentPtr m_docPtr; //member Configuration() { try { HRESULT hr = m_docPtr.CreateInstance(__uuidof(MSXML2::DOMDocument40)); if ( SUCCEEDED(hr)) { m_docPtr->loadXML(CreateXML()); } else { //throw exception to caller } } catch(...) { //throw exception to caller } } Based on Scott Myers RAII implementations in More Effective C++ I believe I am alright in just allowing exceptions to be thrown from CTOR as I am using a smart pointer(IXMLDOMDocumentPtr). Let me know what you think....

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  • System.Data.OracleClient requires Oracle client software version 8.1.7 or greater

    - by sachin kulkarni
    I have installed Oracle client version 10g on my PC(Registry ORACLE_BASE-D:\oracle\product\10.2.0). I have added below references. System.Data.OracleClient. I am getting above mentioned error. Below is the Code Snippet . public static OracleConnection getConnection() { try { dataSource = new SqlDataSource(); dataSource.ConnectionString = System.Configuration.ConfigurationManager.AppSettings.Get("conn"); OracleConnection connection = new OracleConnection(); if (dataSource == null) { // Error during initialization of InitialContext or Datasource throw new Exception("###### Fatal Exception ###### - DataSource is not initialized.Pls check the stdout/logs."); } else { connection.ConnectionString = dataSource.ConnectionString; connection.Open(); } return connection; }catch (Exception ex) { throw ex; } } Please let me know what are the areas of Concern and where Iam missing.I am new for the combination of Oracle and Asp.Net.

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  • How to write java program to increase file limit using ulimit

    - by Sunil Kumar Sahoo
    I am using Fedora linux where ulimit -n 10000 increases file limit upto 10000. I want to achieve the same using java program How to write java program to increase file limit using ulimit I have tried with the below program but it didnot work well. The program didnot give any error. but didnot increase file limit also public class IncreaseFIle { public static void main(String[] args) { String command = "/bin/bash ulimit -n 10000"; // String command = "pwd"; try { Runtime.getRuntime().exec(command); } catch (IOException ex) { ex.printStackTrace(); } } } Thanks Sunil Kumar Sahoo

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  • Can a http server detect that a client has cancelled their request?

    - by Nick Retallack
    My web app must process and serve a lot of data to display certain pages. Sometimes, the user closes or refreshes a page while the server is still busy processing it. This means the server will continue to process data for several minutes only to send it to a client who is no longer listening. Is it possible to detect that the connection has been broken, and react to it? In this particular project, we're using Django and NginX, or Apache. I assumed this is possible because the Django development server appears to react to cancelled requests by printing Broken Pipe exceptions. I'd love to have it raise an exception that my application code could catch. Alternatively, I could register an unload event handler on the page in question, have it do a synchronous XHR requesting that the previous request from this user be cancelled, and do some kind of inter-process communication to make it so. Perhaps if the slower data processing were handed to another process that I could more easily identify and kill, without killing the responding process...

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  • How to get "paster request" to use config host value instead of localhost?

    - by mmartinez
    I'm trying to access my pylons application via cron job to send notifications to my users. The way I'm doing this is by running the application using something like: paster request myconfig.ini /maintenance/do In the actual controller I check for the "paste.command_request" to block public access. Everything works but the only problem is that within the notifications that I send to my users there is a link to their profile and the host is "localhost" which should instead be the domain name of the application. When the notifications are sent from within the served application (say, a user modifies their settings on the site) the notifications have the correct url. I am using mako to render my email tamplates and within the template I am using the "pylons.url" method with "qualified" set to "True". Am I missing something here? Thanks in advance.

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  • allowing index access only with .htaccess

    - by YsoL8
    Hello I have this in my .htaccess file, in the site root: Options -Indexes <directory ../.*> Deny from all </directory> <Files .htaccess> order allow,deny deny from all </Files> <Files index.php> Order allow,deny allow from all </Files> What I'm trying to achieve is to block folder and file access to anything that isn't called index.php, regardless of which directory is accessed. I have the folder part working perfectly and the deny from all rule is working as well - but my attempt to allow access to index.php is failing. Basically could someone tell me how to get it working?

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  • translate by replacing words inside existing text

    - by Berry Tsakala
    What are common approaches for translating certain words (or expressions) inside a given text, when the text must be reconstructed (with punctuations and everythin.) ? The translation comes from a lookup table, and covers words, collocations, and emoticons like L33t, CUL8R, :-), etc. Simple string search-and-replace is not enough since it can replace part of longer words (cat dog ? caterpillar dogerpillar). Assume the following input: s = "dogbert, started a dilbert dilbertion proces cat-bert :-)" after translation, i should receive something like: result = "anna, started a george dilbertion process cat-bert smiley" I can't simply tokenize, since i loose punctuations and word positions. Regular expressions, works for normal words, but don't catch special expressions like the smiley :-) but it does . re.sub(r'\bword\b','translation',s) ==> translation re.sub(r'\b:-\)\b','smiley',s) ==> :-) for now i'm using the above mentioned regex, and simple replace for the non-alphanumeric words, but it's far from being bulletproof. (p.s. i'm using python)

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  • Lazy evaluation in Ruby

    - by fifigyuri
    I have a situation for Ruby, where an object is possibly necessary to be created, but it is not sure. And as the creation of the object might be costly I am not too eager creating it. I think this is a clear case for lazy loading. How can I define an object which is not created only when someone sends a message to it? The object would be created in a block. Is there a way for simple lazy loading/initialisation in Ruby? Are these things supported by some gems, which provide different solutions for various cases of lazy initialisation of objects? Thanks for your suggestions!

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  • Rails 3: config/initializers errors for gem configuration

    - by neezer
    I'm trying to setup this plugin (Crumble), and the docs say I need to add a configuration file for the plugin in config/initializers/ like this (breadcrumb.rb): Breadcrumb.configure do ... end I add in my directives in that block, and reloaded the page, and I'm immediately greeted with a Passenger error: uninitialized constant Breadcrumb What am I missing here? gem list shows Crumble as installed, and if I launch IRB I can require 'crumble' successfully. I remember doing this just fine in Rails 2.3.5. Here's my setup: rails 3.0.0.beta3 ruby 1.9.1p378 (via RVM) passenger 2.2.11 (with Apache2) crumble 0.1.2 I've been trying to read the Rails 3 release notes to see if they've changed anything that would affect this, but so far I haven't found anything to suggest that the above shouldn't work. I'd appreciate any guidance you could spare me!

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  • What are the best options for a root filesystem hosted on SSD under Linux

    - by stsquad
    I'm working on an embedded system which is going to be booting and hosting it's rootfs on an SSD disk. We are currently looking at using Intel X-18M SSDs. The file system structure will have a fairly static /usr section (modulo software upgrades) and an active /var and /var/log for maintaining state and logging. Given the wear-levelling done by the underlying flash does having separate partitions help or hinder? As modern SSDs appear as straight block devices and hide their mapping magic behind their firmware is there any point trying to optimise the choice of file-system that sits on-top of the SSD? Finally does enable SMART monitoring make any sense in this context or are their SSD specific ways of determining the underlying health of the storage hardware?

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  • Can't set anchor tag to [disabled] in IE

    - by Alex
    Hi. I have the following css code. button.png is image where 3 button states are pasted vetrically, so i just move image in css. a.button { background-image: url(button.png); background-position: 0px 0px; width: 100px; height: 30px; display: block; background-repeat: no-repeat; text-indent: -9999px; } a:hover.button { background-position: -100px 0px; } a.button[disabled] { background-position: -200px 0px; cursor:default; } I put this in html <a href="#" class="button" disabled="disabled"></a> In Chrome all is ok. IE dont show disabled image.

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  • How to display characters in http get response correctly with the right encoding

    - by DixieFlatline
    Hello! Does anyone know how to read c,š,ž characters in http get response properly? When i make my request in browser the browser displays all characters correctly. But in java program with apache jars i don't know how to set the encoding right. I tried with client.getParams().setParameter(CoreProtocolPNames.HTTP_CONTENT_CHARSET, "UTF-8"); but it's not working. My code: HttpClient client = new DefaultHttpClient(); String getURL = "http://www.google.com"; HttpGet get = new HttpGet(getURL); HttpResponse responseGet = client.execute(get); HttpEntity resEntityGet = responseGet.getEntity(); if (resEntityGet != null) { Log.i("GET RESPONSE",EntityUtils.toString(resEntityGet)); } } catch (Exception e) { e.printStackTrace(); }

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  • Castle Windsor: Inject NameValueCollection vs. Dictionary

    - by Aren B
    I've already done many configs where dictionaries are passed into services in the <parameters> block. But what I find myself needing right now is to build a NameValueCollection (allowing multiple entries with the same key) or a Collection of KeyValuePair objects. The reason for this is im not using this dictionary to look up b when given a, im basically using it to pass in a Tuple (pair) of (a,b) to be used later in code. Im kind of new to castle windor and I was wondering how i would go about making a List of KeyValuePair's injected, or a NameValueCollection injected.

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  • How to sort a gridview once a radio button is selected

    - by metashockwave
    I'm trying to sort records in the gridview right after a radio button is selected. My approach is with the dataview, but because the dataset variable doesn't survive a round trip to the server, I don't know how to make this happen. please help! Public Sub GetCustomers() db.RunProcedure("usp_customers_get_all") db.doSort(radList.SelectedValue) gvCustomers.DataSource = db.MyView End Sub Protected Sub radList_SelectedIndexChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles radList.SelectedIndexChanged If radList.SelectedValue = 0 Then db.doSort(0) gvCustomers.DataSource = db.MyView End If If radList.SelectedValue = 1 Then db.doSort(1) gvCustomers.DataSource = db.MyView End If End Sub Public Sub doSort(ByVal strIn As Integer) If strIn = 0 Then MyView.Sort = "lastname, firstname" Else MyView.Sort = "username" End If End Sub Public Sub RunProcedure(ByVal strName As String) Dim objConnection As New SqlConnection(mstrConnection) Dim mdbDataAdapter As New SqlDataAdapter(strName, objConnection) Try mdbDataAdapter.SelectCommand.CommandType = CommandType.StoredProcedure Me.mDataset.Clear() mdbDataAdapter.Fill(mDataset, "tblCustomers") MyView.Table = mDataset.Tables("tblCustomers") Catch ex As Exception Throw New Exception("stored procedure is " & strName.ToString & " error is " & ex.Message) End Try End Sub

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  • Flex Datagrid editing calls from same row not firing collection change event

    - by Chin
    Hi, I am using the flex datagrid to allow the user to edit some data. My update process relies on a CollectionEvent of type update. Basically I catch this event package the values and update the database. However, if the user edits a cell then moves to edit a cell in the same row the value of the parameter in the object is updated but a collection event is not fired. Only when clicking out of the row the event is fired. Has anyone had experience with this. I have heard the datagrid is a little quirky is this one of those quirks or am I doing this all wrong? Any help appreciated.

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  • controlling if exceptions are swallowed by a static boolean

    - by sandis
    So we are a few guys developing this product that is communicating with a really unstable server. It often returns very strange and corrupt data. During testing we want the resulting crashes to be loud, so we discover them. But every other day we need to demonstrate our product for a potential customer. To the customer the errors will go undiscovered if we just swallow them. I am thinking about implementing something like this around all server communication to quickly switch between swallowing exceptions and crashing: try { apiCall(); } catch (Exception e) { if(!SWALLOW_EXCEPTION) { throw e; } } Is this an awesome idea, or can it be done in a better way?

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  • Iterator blocks in Clojure?

    - by Checkers
    I am using clojure.contrib.sql to fetch some records from an SQLite database. (defn read-all-foo [] (with-connection *db* (with-query-results res ["select * from foo"] (into [] res)))) Now, I don't really want to realize the whole sequence before returning from the function (i.e. I want to keep it lazy), but if I return res directly or wrap it some kind of lazy wrapper (for example I want to make a certain map transformation on result sequence), SQL-related bindings will be reset and connection will be closed after I return, so realizing the sequence will throw an exception. How can I enclose the whole function in a closure and return a kind of iterator block (like yield in C# or Python)? Or is there another way to return a lazy sequence from this function?

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  • How do I add a textbox to my other jQuery click function?

    - by marcamillion
    Right now, my script adds a box to the cursor when I click on an image, as can be seen in the following code. Please note, this is jQuery. $(function() { var tag_box = $("<div>").appendTo("body").css({"width":"40px", "height":"40px", "border":"4px solid #000000", "position":"absolute", "display":"none", "padding":"15px"}); $("#image-wrapper").live('click', function(e){ tag_box.css({"left": e.pageX - 40, "top": e.pageY - 40, "display":"block"}); }); I would like to add a text field to appear right below that tag_box on that same click. I tried to do this, but it hasn't worked out like I thought it would: var comment_box = $("<label> Comment: <input type='text' name='comment' autocomplete='off'></label>"); $("#image-wrapper").live('click', function(){ $("body").append(comment_box); }); Any assistance you can give me, would be greatly appreciated. Thanks.

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  • triying to do a combo select with this.val() but it doesnt show the second select

    - by irenkai
    Im triying to do a combo where the when the user selects Chile out of the select box, a second select shows up showing the cities. The jQuery code Im using is this. $(document).ready(function(){var ciudad = $("#ciudad"); ciudad.css("display","none"); $("select#selectionpais").change(function(){ var hearValue = $("select#selectionpais").val(); if( hearValue == "chile"){ ciudad.css("display","block"); ; }else{ ciudad.css("display","none") } }); }); and the Html is this (abreviated for the sake of understanding) <select name="pais" id="selectionpais"> .... Chile Afganistán and the second select (the one that should be shown is this) <select id="ciudad" name="ciudad" class="ciudad"> Santiago Anyone has a clue why it isnt working?

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  • Android: Enable selection in webkit

    - by tacone
    Hello, I'am looking for a way to have a webview content selectable in the very same way as the stock browser does. user long presses the text the whole word is selected two pins appear at the word's boundary allowing the user to stretch/shrink the selection. I should note that Dolphin HD shows exactly the same text select functionality as the default browser (same icons, animation, etc), so it really should be possible. But I can't figure out how. Until now, all i found was this function, which kind of work, but doesn't allow the user to expand/shrink the selection. public void selectAndCopyText() { try { KeyEvent shiftPressEvent = new KeyEvent(0,0,KeyEvent.ACTION_DOWN,KeyEvent.KEYCODE_SHIFT_LEFT,0,0); shiftPressEvent.dispatch(mWebView); } catch (Exception e) { throw new AssertionError(e); } }

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  • android camera preview blank screen

    - by user1104836
    I want to capture a photo manually not by using existing camera apps. So i made this Activity: public class CameraActivity extends Activity { private Camera mCamera; private Preview mPreview; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_camera); // Create an instance of Camera // mCamera = Camera.open(0); // Create our Preview view and set it as the content of our activity. mPreview = new Preview(this); mPreview.safeCameraOpen(0); FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview); preview.addView(mPreview); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.activity_camera, menu); return true; } } This is the CameraPreview which i want to use: public class Preview extends ViewGroup implements SurfaceHolder.Callback { SurfaceView mSurfaceView; SurfaceHolder mHolder; //CAM INSTANCE ================================ private Camera mCamera; List<Size> mSupportedPreviewSizes; //============================================= /** * @param context */ public Preview(Context context) { super(context); mSurfaceView = new SurfaceView(context); addView(mSurfaceView); // Install a SurfaceHolder.Callback so we get notified when the // underlying surface is created and destroyed. mHolder = mSurfaceView.getHolder(); mHolder.addCallback(this); mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); } /** * @param context * @param attrs */ public Preview(Context context, AttributeSet attrs) { super(context, attrs); // TODO Auto-generated constructor stub } /** * @param context * @param attrs * @param defStyle */ public Preview(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // TODO Auto-generated constructor stub } /* (non-Javadoc) * @see android.view.ViewGroup#onLayout(boolean, int, int, int, int) */ @Override protected void onLayout(boolean arg0, int arg1, int arg2, int arg3, int arg4) { // TODO Auto-generated method stub } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { // Now that the size is known, set up the camera parameters and begin // the preview. Camera.Parameters parameters = mCamera.getParameters(); parameters.setPreviewSize(width, height); requestLayout(); mCamera.setParameters(parameters); /* Important: Call startPreview() to start updating the preview surface. Preview must be started before you can take a picture. */ mCamera.startPreview(); } @Override public void surfaceCreated(SurfaceHolder holder) { // TODO Auto-generated method stub } @Override public void surfaceDestroyed(SurfaceHolder holder) { // Surface will be destroyed when we return, so stop the preview. if (mCamera != null) { /* Call stopPreview() to stop updating the preview surface. */ mCamera.stopPreview(); } } /** * When this function returns, mCamera will be null. */ private void stopPreviewAndFreeCamera() { if (mCamera != null) { /* Call stopPreview() to stop updating the preview surface. */ mCamera.stopPreview(); /* Important: Call release() to release the camera for use by other applications. Applications should release the camera immediately in onPause() (and re-open() it in onResume()). */ mCamera.release(); mCamera = null; } } public void setCamera(Camera camera) { if (mCamera == camera) { return; } stopPreviewAndFreeCamera(); mCamera = camera; if (mCamera != null) { List<Size> localSizes = mCamera.getParameters().getSupportedPreviewSizes(); mSupportedPreviewSizes = localSizes; requestLayout(); try { mCamera.setPreviewDisplay(mHolder); } catch (IOException e) { e.printStackTrace(); } /* Important: Call startPreview() to start updating the preview surface. Preview must be started before you can take a picture. */ mCamera.startPreview(); } } public boolean safeCameraOpen(int id) { boolean qOpened = false; try { releaseCameraAndPreview(); mCamera = Camera.open(id); mCamera.startPreview(); qOpened = (mCamera != null); } catch (Exception e) { // Log.e(R.string.app_name, "failed to open Camera"); e.printStackTrace(); } return qOpened; } Camera.PictureCallback mPicCallback = new Camera.PictureCallback() { @Override public void onPictureTaken(byte[] data, Camera camera) { // TODO Auto-generated method stub Log.d("lala", "pic is taken"); } }; public void takePic() { mCamera.startPreview(); // mCamera.takePicture(null, mPicCallback, mPicCallback); } private void releaseCameraAndPreview() { this.setCamera(null); if (mCamera != null) { mCamera.release(); mCamera = null; } } } This is the Layout of CameraActivity: <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".CameraActivity" > <FrameLayout android:id="@+id/camera_preview" android:layout_width="0dip" android:layout_height="fill_parent" android:layout_weight="1" /> <Button android:id="@+id/button_capture" android:text="Capture" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" /> </LinearLayout> But when i start the CameraActivity, i just see a blank white background and the Capture-Button??? Why i dont see the Camera-Screen?

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  • How to pass email from one form to another page's form with javascript

    - by zac
    I am trying to have an email signup form on one page populate the email block on another page by passing it through the url and pulling it out with document.write. The first form is something like: <form action="/sign-up"> <input type="text" name="passEmail"><input type="submit"></form> And the recieving form is like : <form name="theForm"> <input type='text' name='email'></form> And I am trying a script like this <SCRIPT LANGUAGE="javascript"> var locate = window.location document.theForm.email.value = locate var text = document.theForm.email.value function delineate(str) { theEmail = str.indexOf("=") + 1; return(str.substring(theEmail)); } document.write(delineate(text)); </SCRIPT> Instead of pulling the email after the = in the url it is pulling the entire url. Can someone help me accomplish this?

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  • Watching a variable for changes without polling.

    - by milkfilk
    I'm using a framework called Processing which is basically a Java applet. It has the ability to do key events because Applet can. You can also roll your own callbacks of sorts into the parent. I'm not doing that right now and maybe that's the solution. For now, I'm looking for a more POJO solution. So I wrote some examples to illustrate my question. Please ignore using key events on the command line (console). Certainly this would be a very clean solution but it's not possible on the command line and my actual app isn't a command line app. In fact, a key event would be a good solution for me but I'm trying to understand events and polling beyond just keyboard specific problems. Both these examples flip a boolean. When the boolean flips, I want to fire something once. I could wrap the boolean in an Object so if the Object changes, I could fire an event too. I just don't want to poll with an if() statement unnecessarily. import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; /* * Example of checking a variable for changes. * Uses dumb if() and polls continuously. */ public class NotAvoidingPolling { public static void main(String[] args) { boolean typedA = false; String input = ""; System.out.println("Type 'a' please."); while (true) { InputStreamReader isr = new InputStreamReader(System.in); BufferedReader br = new BufferedReader(isr); try { input = br.readLine(); } catch (IOException ioException) { System.out.println("IO Error."); System.exit(1); } // contrived state change logic if (input.equals("a")) { typedA = true; } else { typedA = false; } // problem: this is polling. if (typedA) System.out.println("Typed 'a'."); } } } Running this outputs: Type 'a' please. a Typed 'a'. On some forums people suggested using an Observer. And although this decouples the event handler from class being observed, I still have an if() on a forever loop. import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.util.Observable; import java.util.Observer; /* * Example of checking a variable for changes. * This uses an observer to decouple the handler feedback * out of the main() but still is polling. */ public class ObserverStillPolling { boolean typedA = false; public static void main(String[] args) { // this ObserverStillPolling o = new ObserverStillPolling(); final MyEvent myEvent = new MyEvent(o); final MyHandler myHandler = new MyHandler(); myEvent.addObserver(myHandler); // subscribe // watch for event forever Thread thread = new Thread(myEvent); thread.start(); System.out.println("Type 'a' please."); String input = ""; while (true) { InputStreamReader isr = new InputStreamReader(System.in); BufferedReader br = new BufferedReader(isr); try { input = br.readLine(); } catch (IOException ioException) { System.out.println("IO Error."); System.exit(1); } // contrived state change logic // but it's decoupled now because there's no handler here. if (input.equals("a")) { o.typedA = true; } } } } class MyEvent extends Observable implements Runnable { // boolean typedA; ObserverStillPolling o; public MyEvent(ObserverStillPolling o) { this.o = o; } public void run() { // watch the main forever while (true) { // event fire if (this.o.typedA) { setChanged(); // in reality, you'd pass something more useful notifyObservers("You just typed 'a'."); // reset this.o.typedA = false; } } } } class MyHandler implements Observer { public void update(Observable obj, Object arg) { // handle event if (arg instanceof String) { System.out.println("We received:" + (String) arg); } } } Running this outputs: Type 'a' please. a We received:You just typed 'a'. I'd be ok if the if() was a NOOP on the CPU. But it's really comparing every pass. I see real CPU load. This is as bad as polling. I can maybe throttle it back with a sleep or compare the elapsed time since last update but this is not event driven. It's just less polling. So how can I do this smarter? How can I watch a POJO for changes without polling? In C# there seems to be something interesting called properties. I'm not a C# guy so maybe this isn't as magical as I think. private void SendPropertyChanging(string property) { if (this.PropertyChanging != null) { this.PropertyChanging(this, new PropertyChangingEventArgs(property)); } }

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