Search Results

Search found 5174 results on 207 pages for 'prevent'.

Page 185/207 | < Previous Page | 181 182 183 184 185 186 187 188 189 190 191 192  | Next Page >

• wxpython - Running threads sequentially without blocking GUI

  - by ryantmer

  I've got a GUI script with all my wxPython code in it, and a separate testSequences module that has a bunch of tasks that I run based on input from the GUI. The tasks take a long time to complete (from 20 seconds to 3 minutes), so I want to thread them, otherwise the GUI locks up while they're running. I also need them to run one after another, since they all use the same hardware. (My rationale behind threading is simply to prevent the GUI from locking up.) I'd like to have a "Running" message (with varying number of periods after it, i.e. "Running", "Running.", "Running..", etc.) so the user knows that progress is occurring, even though it isn't visible. I'd like this script to run the test sequences in separate threads, but sequentially, so that the second thread won't be created and run until the first is complete. Since this is kind of the opposite of the purpose of threads, I can't really find any information on how to do this... Any help would be greatly appreciated. Thanks in advance! gui.py import testSequences from threading import Thread #wxPython code for setting everything up here... for j in range(5): testThread = Thread(target=testSequences.test1) testThread.start() while testThread.isAlive(): #wait until the previous thread is complete time.sleep(0.5) i = (i+1) % 4 self.status.SetStatusText("Running"+'.'*i) testSequences.py import time def test1(): for i in range(10): print i time.sleep(1) (Obviously this isn't the actual test code, but the idea is the same.)

  Read the article

• java.lang.IllegalStateException: The content of the adapter has changed but ListView.... inspite of calling notifydatasetchanged()

  - by Mistaken

  What are the best practices to be followed to update the contents of a listactivty by a background thread (Async Task) ? 1) Am calling the notifyDataSetChanged() to update the adapter as soon as i manipulate the contents of the adapter but still my app force closes while the user scrolls or click on the list. Any pointers to prevent this would be very helpfull. Logcat: java.lang.IllegalStateException: The content of the adapter has changed but ListView did not receive a notification. 2) Where exaclty should i update contents of the listactivity ? inside the doInBackground() or onProgressUpdate()? 3) Am experiencing regular crashes when the user clicks the list item. So will disabling click events on the listactivty during the background operation solve the problem ? If so am not sure how to remove or set item click listeners dynamically to the listactivity. Please instruct me on the too. 4) I dont think blocking all ui interactions during the background async task execution is the only way to solve the problem. I know there is a simple way of doing this but need some help. Thanks in advance. This is my onCreate... protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.fa); tvStatus=(TextView) findViewById(R.id.tvStatus); adapter = new SimpleAdapter( this, mostPopularList, R.layout.list_item, new String[] {"title","author","views","date"}, new int[] {R.id.textView1,R.id.textView2,R.id.textView4,R.id.textView3}); //populateList(); setListAdapter(adapter); } My async task... private class LongOperation extends AsyncTask<String, Void, String> { @Override protected String doInBackground(String... params) { // code for adding new listactivty items } @Override protected void onPostExecute(String networkStatus) { adapter.notifyDataSetChanged(); } @Override protected void onPreExecute() { } @Override protected void onProgressUpdate(Void... values) { } }

  Read the article

• Doesn't this defeat the whole purpose of having read-only properties?

  - by flockofcode

  I know how to use properties and I understand that they implicitly call underlying get and set accessors, depending on whether we are writing to or reading from a property. static void Main(string[] args) { A a = new A(); (a.b).i = 100; } class A { private B _b = new B(); public B b { get { return _b; } } } class B { public int i; } What code (a.b).i = 100; essentially does is that first property’s get accessor returns a reference to an object _b, and once we have this reference, we are able to access _b’s members and change their values. Thus, in our example, having read only property only prevents outside code from changing the value of a reference variable _b, but it doesn’t prevent outside code from accessing _b’s members. So it seems that property can only detect whether we are trying to read from or write to a variable ( in our case variable _b ) located on the stack, while it’s not able to detect whether we’re trying to also write to members of an object to which the variable on the stack ( assuming this variable is of reference type ) points to. a) But doesn’t that defeat the whole purpose of having read-only properties? Wouldn’t it be more effective if properties had the ability to also detect whether we’re trying to access members of an object returned by get accessor( assuming backing field is of a reference type )? thank you

  Read the article

• Using new (this) to reuse constructors

  - by Brandon Bodnar

  This came up recently in a class for which I am a teaching assistant. We were teaching the students how to do copy constructors in c++, and the students who were originally taught java asked if you can call one constructor from another. I know the answer to this is no, as they are using the pedantic flag for their code in class, and the old standards do not have support for this. I found on Stackoverflow and other sites a suggestion to fake this using new (this) such as follows class MyClass { private: int * storedValue; public: MyClass(int initialValue = 0) { storedValue = new int(initialValue); } ~ MyClass() { delete storedValue; } MyClass(const MyClass &b) { new (this) MyClass(*(b.storedValue)); } int value() { return *storedValue; } }; This is really simple code, and obviously does not save any code by reusing the constructor, but it is just for example. My question is if this is even standard compliant, and if there are any edge cases that should be considered that would prevent this from being sound code?

  Read the article

• Will these security functions be enough? (PHP)

  - by ggfan

  I am trying to secure my site so I don't have sql injections and xss scripting. Here's my code. //here's the from, for brevity, i just show a field for users to put firstname <form> <label for="first_name" class="styled">First Name:</label> <input type="text" id="first_name" name="first_name" value="<?php if (!empty($first_name)) echo $first_name; ?>" /><br /> //submit button etc </form> if (isset($_POST['submit'])) { //gets rid of extra whitesapce and escapes $first_name = mysqli_real_escape_string($dbc, trim($_POST['first_name'])); //check if $first_name is a string if(!is_string($first_name) { echo "not string"; } //then insert into the database. ....... } mysqli_real_espace_string: I know that this func escapes certain letters like \n \r, so when the data gets inputted into the dbc, it would have '\' next to all the escaped letters? --Will this script be enough to prevent most sql injections? just escaping and checking if the data is a string. For integers values(like users putting in prices), i just: is_numeric(). --How should I use htmlspecialchars? Should I use it only when echoing and displaying user data? Or should I also use this too when inputting data to a dbc? --When should I use strip_tags() or htmlspecialchars? SOO with all these function... if (isset($_POST['submit'])) { //gets rid of extra whitesapce and escapes $first_name = mysqli_real_escape_string($dbc, trim($_POST['first_name'])); //check if $first_name is a string if(!is_string($first_name) { echo "not string"; } //gets rid of any <,>,& htmlspecialchars($first_name); //strips any tags with the first name strip_tags($first_name) //then insert into the database. ....... } Which funcs should I use for sql injections and which ones should I use for xss?

  Read the article

• Add a banner at the top on unknown HTML page on the fly; Send a note to network user

  - by Vi

  I want to be able to send messages to users of network that my computer routes to. Modifying requested pages, by adding messages like Warning: this access point is going down soon" or Network quota exhausted or You are overusing the network connection and may be banned or Security notice: this is unencrypted network, so everybody around can see this page too It seems the only good solution (as there is no general "Send notice to users of my access point" thing). All traffic is already routed through -j REDIRECT, socat and remote SOCSK5 server, so intercepting unencrypted content should be easy. How it's better to add a message? Just inserting <div style="color:white; background-color:red">Sorry, connect_me access point is going down soon...</div> as the first element of <body> breaks design of some pages (f.e. Wikipedia). Should I also add some "Cache-control" directive to prevent persisting such messages? /* smdclient messages are poor solution, as them are Windows-only and can disturb users not using the network */

  Read the article

• What are your best practices for ensuring the correctness of the reports from SQL?

  - by snezmqd4

  Part of my work involves creating reports and data from SQL Server to be used as information for decision. The majority of the data is aggregated, like inventory, sales and costs totals from departments, and other dimensions. When I am creating the reports, and more specifically, I am developing the SELECTs to extract the aggregated data from the OLTP database, I worry about mistaking a JOIN or a GROUP BY, for example, returning incorrect results. I try to use some "best practices" to prevent me for "generating" wrong numbers: When creating an aggregated data set, always explode this data set without the aggregation and look for any obvious error. Export the exploded data set to Excel and compare the SUM(), AVG(), etc, from SQL Server and Excel. Involve the people who would use the information and ask for some validation (ask people to help to identify mistakes on the numbers). Never deploy those things in the afternoon - when possible, try to take a look at the T-SQL on the next morning with a refreshed mind. I had many bugs corrected using this simple procedure. Even with those procedures, I always worry about the numbers. What are your best practices for ensuring the correctness of the reports?

  Read the article

• Password protect user image album

  - by Poland Rocks

  Hi Im making i photo sharint site I want to give the ability for my users to prevent the public to acces their albums with a password. Then they can give the password to the ones they want to be able to see it. To password protect their albums. Im thinking something like this, cant test it on this computer, should work ok. but as im a php/mysql beginner i wanna hear what you experts think if theres a better way/approach Albums id name owner password (if it isnt null the album is considered password protected) The code $id = isset($_GET['albumID']) ? intval($_GET['albumID']) : 0; $result = mysql_query("SELECT * FROM albums WHERE id = $id"); $row = mysql_fetch_object($result); // IS it password protected? if ($row->password != NULL) { echo "This album is password protected."; // User pressed "Enter" if (!empty($_POST['password'])) { $result = mysql_query("SELECT password FROM albums WHERE password = '".mysql_real_escape_string($_POST['password'])."'"); // Was It right password? if (mysql_num_rows($result) == 1) { $authed=1; } echo << <form method="post"> <input type="text" name="password" /> EOT; exit; } else $authed=1; if $authed==1 { // render albumimages etc }

  Read the article

• synchronizing reads to a java collection

  - by jeff

  so i want to have an arraylist that stores a series of stock quotes. but i keep track of bid price, ask price and last price for each. of course at any time, the bid ask or last of a given stock can change. i have one thread that updates the prices and one that reads them. i want to make sure that when reading no other thread is updating a price. so i looked at synchronized collection. but that seems to only prevent reading while another thread is adding or deleting an entry to the arraylist. so now i'm onto the wrapper approach: public class Qte_List { private final ArrayList<Qte> the_list; public void UpdateBid(String p_sym, double p_bid){ synchronized (the_list){ Qte q = Qte.FindBySym(the_list, p_sym); q.bid=p_bid;} } public double ReadBid(String p_sym){ synchronized (the_list){ Qte q = Qte.FindBySym(the_list, p_sym); return q.bid;} } so what i want to accomplish with this is only one thread can be doing anything - reading or updating an the_list's contents - at one time. am i approach this right? thanks.

  Read the article

• NHibernate not dropping foreign key constraints.

  - by Kendrick

  I'm new to NHibernate, so this is probably my mistake, but when I use: schema.Create(true, true); I get: SchemaExport [(null)]- There is already an object named 'XXX' in the database. System.Data.SqlClient.SqlException: There is already an object named 'XXX' in the database. I grabbed the SQL code nHibernate was using, ran it directly from MSSMS, and recieved similar errors. Looking into it, the generated code is not properly dropping the foreign key constraints. The drop looks like this: if exists (select 1 from sysobjects where id = OBJECT_ID(N'dbo[FK22212EAFBFE4C58]') AND parent_obj = OBJECT_ID('YYY')) alter table dbo.YYY drop constraint FK22212EAFBFE4C58 Doing a "select OBJECT_ID(N'dbo[FK22212EAFBFE4C58]')" I get null. If I take out the "dbo" (i.e. "select OBJECT_ID(N'[FK22212EAFBFE4C58]')") then the ID is returned. So, my question is, why is nHibernate adding the dbo, and why does that prevent the object from being returned (since the table owning the constraint is dbo.XXX) One of my mapping files: <?xml version="1.0" encoding="utf-8"?> <hibernate-mapping namespace="CanineApp.Model" assembly="CanineApp.Model" xmlns="urn:nhibernate-mapping-2.2"> <class name="MedicalLog" table="MedicalLog" schema="dbo"> <id name="MedicalLogID" type="Int64"> <generator class="identity" /> </id> <property name="InvoiceAmount" type="Decimal" not-null="true" /> ... <many-to-one name="Canine" class="Canine" column="CanineID" not-null="true" fetch="join" /> <many-to-one name="TreatmentCategory" class="TreatmentCategory" column="TreatmentCategoryID" not-null="true" access="field.camelcase-underscore" /> </class> </hibernate-mapping>

  Read the article

• Thread is being killed by the OS

  - by Or.Ron

  I'm currently programming an app that extracts frames from a movie clip. I designed it so that the extraction will be done on a separate thread to prevent the application from freezing. The extraction process itself is taking a lot of resources, but works fine when used in the simulator. However, there are problems when building it for the iPad. When I perform another action (I'm telling my AV player to play while I extract frames), the thread unexpectedly stops working, and I believe it's being killed. I assume it's becauase I'm using a lot of resources, but not entirely sure. Here are my questions: 1. How can I tell if/why my thread stopping? 2. If it's really from over processing what should I do? I really need this action to be implemented. Heres some code im using: To create the thread: [NSThread detachNewThreadSelector:@selector(startReading) toTarget:self withObject:nil]; I'll post any information you need, Thanks so much! Update I'm using GCD now and it populates the threads for me. However the OS still kills the threads. I know exactly when is it happening. when i tell my [AVplayer play]; it kills the thread. This issue is only happening in the actual iPad and not on the simulator

  Read the article

• How to map string keys to unique integer IDs?

  - by Marek

  I have some data that comes regularily as a dump from a data souce with a string natural key that is long (up to 60 characters) and not relevant to the end user. I am using this key in a url. This makes urls too long and user unfriendly. I would like to transform the string keys into integers with the following requirements: The source dataset will change over time. The ID should be: non negative integer unique and constant even if the set of input keys changes preferrably reversible back to key (not a strong requirement) The database is rebuilt from scratch every time so I can not remember the already assigned IDs and match the new data set to existing IDs and generate sequential IDs for the added keys. There are currently around 30000 distinct keys and the set is constantly growing. How to implement a function that will map string keys to integer IDs? What I have thought about: 1. Built-in string.GetHashCode: ID(key) = Math.Abs(key.GetHashCode()) is not guaranteed to be unique (not reversible) 1.1 "Re-hashing" the built-in GetHashCode until a unique ID is generated to prevent collisions. existing IDs may change if something colliding is added to the beginning of the input data set 2. a perfect hashing function I am not sure if this can generate constant IDs if the set of inputs changes (not reversible) 3. translate to base 36/64/?? does not shorten the long keys enough What are the other options?

  Read the article

• How to speed up drawing of scaled image? Audio playback chokes during window resize.

  - by Paperflyer

  I am writing an audio player for OSX. One view is a custom view that displays a waveform. The waveform is stored as a instance variable of type NSImage with an NSBitmapImageRep. The view also displays a progress indicator (a thick red line). Therefore, it is updated/redrawn every 30 milliseconds. Since it takes a rather long time to recalculate the image, I do that in a background thread after every window resize and update the displayed image once the new image is ready. In the meantime, the original image is scaled to fit the view like this: // The drawing rectangle is slightly smaller than the view, defined by // the two margins. NSRect drawingRect; drawingRect.origin = NSMakePoint(sideEdgeMarginWidth, topEdgeMarginHeight); drawingRect.size = NSMakeSize([self bounds].size.width-2*sideEdgeMarginWidth, [self bounds].size.height-2*topEdgeMarginHeight); [waveform drawInRect:drawingRect fromRect:NSZeroRect operation:NSCompositeSourceOver fraction:1]; The view makes up the biggest part of the window. During live resize, audio starts choking. Selecting the "big" graphic card on my Macbook Pro makes it less bad, but not by much. CPU utilization is somewhere around 20-40% during live resizes. Instruments suggests that rescaling/redrawing of the image is the problem. Once I stop resizing the window, CPU utilization goes down and audio stops glitching. I already tried to disable image interpolation to speed up the drawing like this: [[NSGraphicsContext currentContext] setImageInterpolation:NSImageInterpolationNone]; That helps, but audio still chokes during live resizes. Do you have an idea how to improve this? The main thing is to prevent the audio from choking.

  Read the article

• Maximize/Minimize is causing Close Button to be re-enabled after disabling it -- Why?

  - by Brainsick

  I have used P/Invoke to call GetSystemMenu and EnableMenuItem (win32api) to disable the close functionality. However, after minimizing or maximizing my Windows Forms application the button is re-enabled. Obviously minimizing or maximizing is causing the behavior, but how? I'm not sure where to look to prevent this behavior. Should I be preventing the maximize and minimize behavior or is there something particularly wrong with the way in which I P/Invoked the calls? Once the application (main form) has loaded, I call the static method from a button click. class PInvoke { // P/Invoke signatures [DllImport("user32.dll")] static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert); [DllImport("user32.dll")] static extern bool EnableMenuItem(IntPtr hMenu, uint uIDEnableItem, uint uEnable); // SysCommand (WM_SYSCOMMAND) constant internal const UInt32 SC_CLOSE = 0xF060; // Constants used with Add/Check/EnableMenuItem internal const UInt32 MF_BYCOMMAND = 0x00000000; internal const UInt32 MF_ENABLED = 0x00000000; internal const UInt32 MF_GRAYED = 0x00000001; internal const UInt32 MF_DISABLED = 0x00000002; /// <summary> /// Sets the state of the Close (X) button and the System Menu close functionality. /// </summary> /// <param name="window">Window or Form</param> /// <param name="bEnabled">Enabled state</param> public static void EnableCloseButton(IWin32Window window, bool bEnabled) { IntPtr hSystemMenu = GetSystemMenu(window.Handle, false); EnableMenuItem(hSystemMenu, SC_CLOSE, MF_BYCOMMAND | (bEnabled ? MF_ENABLED : MF_GRAYED)); } }

  Read the article

• Perl Capture and Modify STDERR before it prints to a file

  - by MicrobicTiger

  I have a perl script which performs multiple external commands and prints the outputs from STDERR and STDOUT to a logfile along with a series of my own print statements to act as documentation on the process. My problem is that the STDERR repeats ~identical prints as example below. I'd like to capture this before it prints and replace with the final result for each of the commands i run. blocks evaluated : 0 blocks evaluated : 10000 blocks evaluated : 20000 blocks evaluated : 30000 ... blocks evaluated : 3420000 blocks evaluated : 3428776 Here's how I'm getting STDOUT and STDERR my $logfile = "Logfile.log"; #log file name #--- Open log file for append if specified --- if ( $logfile ) { open ( OLDOUT, ">&", STDOUT ) or die "ERROR: Can't backup STDOUT location.\n"; close STDOUT; open ( STDOUT, ">", $logfile ) or die "ERROR: Logfile [$logfile] cannot be opened.\n"; } if ( $logfile ) { open ( OLDERR, ">&", STDERR ) or die "ERROR: Can't backup STDERR location.\n"; close STDERR; open ( STDERR, '>&STDOUT' ) or die "ERROR: failed to pass STDERR to STDOUT.\n"; } and closing them close STDERR; open ( STDERR, ">&", OLDERR ) or die "ERROR: Can't fix that first thing you broke!\n"; close STDOUT; open ( STDOUT, ">&", OLDOUT ) or die "ERROR: Can't fix that other thing you broke!\n"; How do I access the STDERR when each print is occurring to do the replace? Or prevent it from printing if it isn't the last of the batch. Many Thanks in advance.

  Read the article

• Android while getting HTTP response to file how to know it wasn't fully loaded?

  - by Stan

  I'm using this approach to store a big-sized response from server to parse it later: final HttpClient client = new DefaultHttpClient(new BasicHttpParams()); final HttpGet mHttpGetRequest = new HttpGet(strUrl); mHttpGetRequest.setHeader("Content-Type", "application/x-www-form-urlencoded"); FileOutputStream fos = null; try { final HttpResponse response = client.execute(mHttpGetRequest); final StatusLine statusLine = response.getStatusLine(); lastHttpErrorCode = statusLine.getStatusCode(); lastHttpErrorMsg = statusLine.getReasonPhrase(); if (lastHttpErrorCode == 200) { HttpEntity entity = response.getEntity(); fos = new FileOutputStream(reponseFile); entity.writeTo(fos); entity.consumeContent(); fos.flush(); } } catch (ClientProtocolException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (final ParseException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (final UnknownHostException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); return null; } catch (IOException e) { e.printStackTrace(); lastHttpErrorMsg = e.toString(); } finally{ if (fos!=null) try{ fos.close(); } catch (IOException e){} } now how could I ensure the response was completely received and thus saved to file? Assume client's device lost Internet connection while this code was running. So the app received only some part of real response. And I'm pretty sure it happens cuz I got parsing exceptions like "tag not closed", "unexpected end of file" etc. So I need to detect somehow this situation to prevent code from parsing partial response but can't see how. Is it possible at all and how to do it? Or has it has to raise IOException in such cases?

  Read the article

• JavaScript Key Codes

  - by Jonathan Wood

  I'm working with a JavaScript routine I didn't write. It is called from a text box's onkeydown attribute to prevent unwanted keystrokes. The first argument is apparently not used. The second argument is a list of characters that should be allowed. function RestrictChars(evt, chars) { var key; var keychar; if (window.event) key = window.event.keyCode; else if (e) key = e.which; else return true; keychar = String.fromCharCode(key); if ((key == null) || (key == 0) || (key == 8) || (key == 9) || (key == 13) || (key == 27)) // Control key return true; else if (((chars).indexOf(keychar) > -1)) return true; else return false; } This seems to work for alpha-numeric characters. However, characters such as . and / cause this function to return false, even when these characters are included in the chars parameter. For example, if the . key is pressed, key is set to 190, and keychar gets set to the "3/4" character. Can anyone see how this was meant to work and/or why it doesn't? I don't know enough about JavaScript to see what it's trying to do.

  Read the article

• Making IE "forget" information entered in form when using back button.

  - by typoknig

  I have a page with a form where many of the fields are populated from variables passed in the URL. Those fields are disabled (NON-EDITABLE) and are only there for the user to view. The remaining fields require user input and are NOT disabled (EDITABLE). When the form is submitted a confirmation page comes up. It may be the case that the user needs to submit several of these forms where the NON-EDITABLE information is identical from form to form, so being able to go back to the form page from the confirmation page would save a lot of time. The way I want this to work is when a user presses the back button all the NON-EDITABLE fields are populated, but the EDITABLE fields are blank. This is what Firefox is doing, but IE8 is does not "forget" what has been entered in the EDITABLE fields. To disable the cache the following appears at the beginning of my page AND at the end of my page. <head> <meta http-equiv="Pragma" content="no-cache"/> <meta http-equiv="Cache-Control" content="no-store"/> <head/> What more must I do to make IE forget what was entered in the EDITABLE fields when the back button is pressed? All of my pages are generated with PHP if that matters. EDIT: It appears to me that this is a problem of IE caching my page even though I have told it not to. Are my meta tags correct? Do I need to do something else to prevent IE from caching my page?

  Read the article

• jQuery $.each()-problem

  - by Volmar

  Hi, im making a wordpress plugin and i have a function where i import images, this is done with a $.each()-loop that calls a .load()-function every iteration. The load-function page the load-function calls is downloading the image and returns a number. The number is imported into a span-element. The source and destination Arrays is being imported from LI-elemnts of a hidden ULs. this way the user sees a counter counting from zero up to the total number of images being imported. You can se my jQuery code below: jQuery(document).ready(function($) { $('#mrc_imp_img').click(function(){ var dstA = []; var srcA = []; $("#mrc_dst li").each(function() { dstA.push($(this).text()) }); $("#mrc_src li").each(function() { srcA.push($(this).text()) }); $.each(srcA, function (i,v) { $('#mrc_imgimport span.fc').load('/wp-content/plugins/myplugin/imp.php?num='+i+'&dst='+dstA[i]+'&src='+srcA[i]); }); }); }); This works pretty good but sometimes it looks like the load function isn't updating the DOM as fast as it should because sometimes the numbers that the span is updated with is lower than the previous and almost everytime a lower number is replacing the last number in the end. How can i prevent this from happening and how can i make it hide '#mrc_imp_img' when the $.each-loop is ready?

  Read the article

• How do I make this Java code operate properly? [Multi-threaded, race condition]

  - by Fixee

  I got this code from a student, and it does not work properly because of a race condition involving x++ and x--. He added synchronized to the run() method trying to get rid of this bug, but obviously this only excludes threads from entering run() on the same object (which was never a problem in the first place) but doesn't prevent independent objects from updating the same static variable x at the same time. public class DataRace implements Runnable { static volatile int x; public synchronized void run() { for (int i = 0; i < 10000; i++) { x++; x--; } } public static void main(String[] args) throws Exception { Thread [] threads = new Thread[100]; for (int i = 0; i < threads.length; i++) threads[i] = new Thread(new DataRace()); for (int i = 0; i < threads.length; i++) threads[i].start(); for (int i = 0; i < threads.length; i++) threads[i].join(); System.out.println(x); // x not always 0! } } Since we cannot synchronize on x (because it is primitive), the best solution I can think of is to create a new static object like static String lock = ""; and enclose the x++ and x-- within a synchronized block, locking on lock. But this seems really awkward. Is there a better way?

  Read the article

• How to keep jquery from descending too far?

  - by Earlz

  Hello, I am having a problem with jquery going a bit too far on pattern matching of CSS classes and IDs. I have some markup that looks like this: <div id="blah"> <div class="level2"> <input type="text" /> </div> <div class="levelA"> <div class="level2"> <input type="text" value="foo"/> </div> </div> </div> <input type="text" value="bar" /> I want for the 3 inputs to say Hello Foo Bar so I have this line of jquery: $('#blah .level2 input').val('hello'); the problem now is that jquery is a bit too liberal in it's pattern matches and matches both the first and second. How can I prevent this kind of thing from happening? A live example is at http://jsbin.com/opelo3/4

  Read the article

• Right border shifts to bottom line

  - by zencimusa

  http://jsfiddle.net/W9LXd/ I want the div under the #araclar to have it's right border stay in the same line. How can I prevent it from shifting? CSS: #düzenleyici{ border: 1px solid #000; width: 600px; height: 300px; box-shadow: 1px 1px 4px #000; } #araclar{ width:auto; height:50px; background:#EEEEEE; display:block; padding:5px 15px 5px 15px; border-bottom:1px solid #000; } #araclar>div{ padding:0 5px 0 5px; display:inline; border:1px solid #000; } HTML: <div id="düzenleyici"> <div id="araclar"> <div> Renk <div> </div> </div>

  Read the article

• Questions about shifting from mysql to PDO

  - by Scarface

  Hey guys I have recently decided to switch all my current plain mysql queries performed with php mysql_query to PDO style queries to improve performance, portability and security. I just have some quick questions for any experts in this database interaction tool Will it prevent injection if all statements are prepared? (I noticed on php.net it wrote 'however, if other portions of the query are being built up with unescaped input, SQL injection is still possible' I was not exactly sure what this meant). Does this just mean that if all variables are run through a prepare function it is safe, and if some are directly inserted then it is not? Currently I have a connection at the top of my page and queries performed during the rest of the page. I took a look at PDO in more detail and noticed that there is a try and catch procedure for every query involving a connection and the closing of that connection. Is there a straightforward way to connecting and then reusing that connection without having to put everything in a try or constantly repeat the procedure by connecting, querying and closing? Can anyone briefly explain in layman's terms what purpose a set_exception_handler serves? I appreciate any advice from any more experienced individuals.

  Read the article

• PHP session token can be used multipletimes?

  - by kornesh

  I got page A which is a normal HTML page and page which is an AJAX response page. And I want to prevent CSRF attacks by tokens. Lets say I use this method for an autocomplete form, is it possible to use same token multiple times (of course the session is only set one time) because i tired this method but the validation keep failing after the first suggestion (obviously the token has changed, somehow) page A <?php session_start(); $token = md5(uniqid(rand(), TRUE)); $_SESSION['token'] = $token; ?> <input id="token" value="<?php echo $token; ?>" type="hidden"></input> <input id="autocomplete" placeholder="Type something"></input> .... The form is autosubmitted every time theres a change using Jquery. page B <?php session_start(); if($_REQUEST['token'] == $_SESSION['token']){ echo 'Im working fine'; } ?>

  Read the article

• Hide form if javascript disabled

  - by Kero

  I need to check on disabling JavaScript if the user disabled JavaScript from browser or firewall or any other place he will never show the form. I have lots of search and solutions, but unfortunately didn't got the right one. - Using style with no-script tag: This one could be broke with removing style... <noscript> <style type="text/css"> .HideClass { display:none; } </style> </noscript> The past code will work just fine but there is lots of problems in no-script tag as here Beside that i don't want to redirect user with no-script tag too...Beside that i can quickly stop loading the page to broke this meta or disable Meta tag from IE: <meta http-equiv="refresh" content="0; URL=Frm_JavaScriptDisable.aspx" /> Another way to redirect user with JavaScript but this will work let's say for 99% of users and this one isn't lovely way and will slow down the website... window.location="http://www.location.com/page.aspx"; Is there is any other ideas or suggestions to secure working with JavaScript...and prevent user from entering the website or see my form except when JavaScript enabled...

  Read the article

< Previous Page | 181 182 183 184 185 186 187 188 189 190 191 192  | Next Page >