Search Results

Search found 21356 results on 855 pages for 'check digit'.

Page 722/855 | < Previous Page | 718 719 720 721 722 723 724 725 726 727 728 729  | Next Page >

  • Best way to use Google's hosted jQuery, but fall back to my hosted library on Google fail

    - by Nosredna
    What would be a good way to attempt to load the hosted jQuery at Google (or other Google hosted libs), but load my copy of jQuery if the Google attempt fails? I'm not saying Google is flaky. There are cases where the Google copy is blocked (apparently in Iran, for instance). Would I set up a timer and check for the jQuery object? What would be the danger of both copies coming through? Not really looking for answers like "just use the Google one" or "just use your own." I understand those arguments. I also understand that the user is likely to have the Google version cached. I'm thinking about fallbacks for the cloud in general. Edit: This part added... Since Google suggests using google.load to load the ajax libraries, and it performs a callback when done, I'm wondering if that's the key to serializing this problem. I know it sounds a bit crazy. I'm just trying to figure out if it can be done in a reliable way or not. Update: jQuery now hosted on Microsoft's CDN. http://www.asp.net/ajax/cdn/

    Read the article

  • Callers block until getFoo() has a value ready?

    - by Sean Owen
    I have a Java Thread which exposes a property which other threads want to access: class MyThread extends Thread { private Foo foo; ... Foo getFoo() { return foo; } ... public void run() { ... foo = makeTheFoo(); ... } } The problem is that it takes some short time from the time this runs until foo is available. Callers may call getFoo() before this and get a null. I'd rather they simply block, wait, and get the value once initialization has occurred. (foo is never changed afterwards.) It will be a matter of milliseconds until it's ready, so I'm comfortable with this approach. Now, I can make this happen with wait() and notifyAll() and there's a 95% chance I'll do it right. But I'm wondering how you all would do it; is there a primitive in java.util.concurrent that would do this, that I've missed? Or, how would you structure it? Yes, make foo volatile. Yes, synchronize on an internal lock Object and put the check in a while loop until it's not null. Am I missing anything?

    Read the article

  • How can I find the common ancestor of two nodes in a binary tree?

    - by Siddhant
    The Binary Tree here is not a Binary Search Tree. Its just a Binary Tree. The structure could be taken as - struct node { int data; struct node *left; struct node *right; }; The maximum solution I could work out with a friend was something of this sort - Consider this binary tree (from http://lcm.csa.iisc.ernet.in/dsa/node87.html) : The inorder traversal yields - 8, 4, 9, 2, 5, 1, 6, 3, 7 And the postorder traversal yields - 8, 9, 4, 5, 2, 6, 7, 3, 1 So for instance, if we want to find the common ancestor of nodes 8 and 5, then we make a list of all the nodes which are between 8 and 5 in the inorder tree traversal, which in this case happens to be [4, 9, 2]. Then we check which node in this list appears last in the postorder traversal, which is 2. Hence the common ancestor for 8 and 5 is 2. The complexity for this algorithm, I believe is O(n) (O(n) for inorder/postorder traversals, the rest of the steps again being O(n) since they are nothing more than simple iterations in arrays). But there is a strong chance that this is wrong. :-) But this is a very crude approach, and I'm not sure if it breaks down for some case. Is there any other (possibly more optimal) solution to this problem?

    Read the article

  • Internal Java code best practice for dealing with invalid REST API parameters

    - by user326389
    My colleague wrote the following stackoverflow question: other stack overflow question on this topic The question seems to have been misinterpreted and I want to find out the answer, so I'm starting this new question... hopefully a little more clear. Basically, we have a REST API. Users of our API call our methods with parameters. But sometimes users call them with the wrong parameters!! Maybe a mistake in their code, maybe they're just trying to play with us, maybe they're trying to see how we respond, who knows! We respond with HTTP status error codes and maybe a detailed description of the invalid parameter in the XML response. All is well. But internally we deal with these invalid parameters by throwing exceptions. For example, if someone looks up a Person object by giving us their profile id, but the profile id doesn't exist... we throw a PersonInvalidException when looking them up. Then we catch this exception in our API controller and send back an HTTP 400 status error code. Our question is... is this the best practice, throwing exceptions internally for this kind of user error? These exceptions never get propogated back to the user, this is a REST API. They only make our code cleaner. Otherwise we could have a validation method in each of our API controllers to make sure the parameters all make sense, but that seems inefficient. We have to look up things in our database potentially twice. Or we could return nulls and check for them, but that sucks... What are your thoughts?

    Read the article

  • C++ trouble with pointers to objects

    - by Zibd
    I have a class with a vector of pointers to objects. I've introduced some elements on this vector, and on my main file I've managed to print them and add others with no problems. Now I'm trying to remove an element from that vector and check to see if it's not NULL but it is not working. I'm filling it with on class Test: Other *a = new Other(1,1); Other *b = new Other(2,2); Other *c = new Other(3,3); v->push_back(a); v->push_back(b); v->push_back(c); And on my main file I have: Test t; (...) Other *pointer = t.vect->at(0); delete t.vect->at(0); t.vect->erase(t.vect->begin()); if (pointer == NULL) { cout << "Nothing here.."; } // Never enters here..

    Read the article

  • XSLT - Comparing preceding-sibling's elements with current's node element

    - by siondream
    Hello, I have this XML file: <recursos> <recurso url="http://w3c.com"> <descripcion>Consorcio W3C</descripcion> <tipo>externo</tipo> <idioma>ingles</idioma> <contenido>General</contenido> <unidad>Unidad 2</unidad> </recurso> <recurso url="http://html.com"> <descripcion>Especificación HTML</descripcion> <tipo>externo</tipo> <idioma>castellano</idioma> <contenido>HTML</contenido> <version>4.01</version> <unidad>Unidad 3</unidad> </recurso> </recursos> I want to compare one "recurso"'s preceding sibling element "unidad" with the "unidad" of the current "recurso" to check if they're different. I was trying: <xsl:if test="preceding-sibling::recurso[position()=1]::unidad != unidad"> </xsl:if> But I know it's horribly wrong :( I hope you could help me, thank you very much.

    Read the article

  • Can JMX operations take interfaces as parameters?

    - by Thor84no
    I'm having problems with an MBean that takes a Map<String, Object> as a parameter. If I try to execute it via JMX using a proxy object, I get an Exception: Caused by: javax.management.ReflectionException at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:231) at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:668) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) Caused by: java.lang.IllegalArgumentException: Unable to find operation updateProperties(java.util.HashMap) It appears that it attempts to use the actual implementation class rather than the interface, and doesn't check if this is a child of the required interface. The same thing happens for extended classes (for example declare HashMap, pass in LinkedHashMap). Does this mean it's impossible to use an interface for such methods? At the moment I'm getting around it by changing the method signature to accept a HashMap, but it seems odd that I wouldn't be able to use interfaces (or extended classes) in my MBeans. Edit: The proxy object is being created by an in-house utility class called JmxInvocationHandler. The (hopefully) relevant parts of it are as follows: public class JmxInvocationHandler implements InvocationHandler { ... public static <T> T createMBean(final Class<T> iface, SFSTestProperties properties, String mbean, int shHostID) { T newProxyInstance = (T) Proxy.newProxyInstance(iface.getClassLoader(), new Class[] { iface }, (InvocationHandler) new JmxInvocationHandler(properties, mbean, shHostID)); return newProxyInstance; } ... private JmxInvocationHandler(SFSTestProperties properties, String mbean, int shHostID) { this.mbeanName = mbean + MBEAN_SUFFIX + shHostID; msConfig = new MsConfiguration(properties.getHost(0), properties.getMSAdminPort(), properties.getMSUser(), properties.getMSPassword()); } ... public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { if (management == null) { management = ManagementClientStore.getInstance().getManagementClient(msConfig.getHost(), msConfig.getAdminPort(), msConfig.getUser(), msConfig.getPassword(), false); } final Object result = management.methodCall(mbeanName, method.getName(), args == null? new Object[] {} : args); return result; } }

    Read the article

  • PHP GET issue - it aint workin!

    - by benhowdle89
    I have a simple PHP form which displays inputs with values from a mysql DB and send the form results to another page which updates a db table based on the GET results: echo "<form method='get' action='updateprojects.php'>"; echo "<table>"; echo "<tr>"; echo " <th>Project No</th> <th>Customer Name</th> <th>Description</th> </tr>"; while($row = mysql_fetch_array($result)) { echo "<tr>"; echo "<td><input value=" . $row['project_no'] . "></input></td>"; echo "<td><input value='" . $row['cust_name'] . "'></input></td>"; echo "<td><input value='" . $row['description'] . "'></input></td>"; echo "</tr>"; } echo "</table>"; echo "<input type='submit' value='Update' />"; echo "</form>"; on updateprojects.php i have set up the GET variable and even echoed them to check but nothing comes through! Cannot see why!? This is the start of updateprojects.php: echo $_GET['project_no'].$_GET['cust_name'].$_GET['description'];

    Read the article

  • Rails 2.3.14 setting expire_after for sessions is ignored

    - by Sergii Shablatovych
    I have next config in my environment.rb: config.action_controller.session_store = :cookie_store config.action_controller.session = { :expire_after => 14.days, :domain => DOMAIN, :session_key => '_session', :secret => 'some_string' } Setting session_store to active_record_store or mem_cache_store didn't help. Also i've tried just setting cookie from controller (with all founded options for expire): cookies[:test] = { :value => 'test' , :expires => 3600.to_i.from_now.utc } In both ways all sessions and cookies are deleted after closing browser window - they are only for browser session. I've tried almost all variants founded in the Internet - no luck( My config is: Ubuntu 10.04 LTS, rails 2.3.14, ruby Enterprise Edition 1.8.7, Phusion Passenger version 3.0.11 and Nginx compiled by Phusion Passenger. I've an options that it's Nginx not allowing setting some headers but also didn't find any solution. Any help appreciated! Thanks UPD. i've tried to put all configs for sessions to config/initializers/session_store.rb - nothing changed. i have a feeling that it's not a rails problem. may it be phusion + nginx error? i don't even know how to check where the problem is.

    Read the article

  • Scanning, Checking, Converting, Copying values ... How to ? -- C --

    - by ZaZu
    Hi there, Its been a while now and im still trying to get a certain code to work. I asked some question about different commands etc. before, but now I hope this is the final one (combining all questions in one code). I basically want to : *Scan an input (should be character ? ) *Check if its a number *If not, return error *Convert that character into a float number *Copy the value to another variable ( I called it imp here) Here is what I came up with : #include<stdio.h> #include<stdlib.h> #include<ctype.h> main(){ int digits; float imp=0; int alpha; do{ printf("Enter input\n\n"); scanf("\n%c",&alpha); digits=isdigit(alpha); if(digits==0){ printf("error\n\n"); } imp=atof(alpha); }while(digits==0); } The problem is this code does not work at all ... It gives me that atof must be of a const char and whenever I try changing it around, it just keeps failing. I am frustrated and forced to ask here, because I believe I have tried alot and I keep failing, but I wont be relieved until I get it to work xD So I really need your help guys. Please tell me why isnt this code working, what am I doing wrong ? I am still learning C and really appreciate your help :)

    Read the article

  • Converting string to a simple type

    - by zespri
    .Net framework contains a great class named Convert that allows conversion between simple types, DateTime type and String type. Also the class support conversion of the types implementing IConvertible interface. The class has been implemented in the very first version of .Net framework. There were a few things in the first .Net framework that were not done quite right. For example .Parse methods on simple types would throw an exception if the string couldn't be parsed and there would be no way to check if exception is going to be thrown in advance. A future version of .Net Framework removed this deficiency by introducing the TryParse method that resolved this problem. The Convert class dates back to time of the old Parse method, so the ChangeType method on this class in implemented old style - if conversion can't be performed an exception is thrown. Take a look at the following code: public static T ConvertString<T>(string s, T @default) { try { return (T)Convert.ChangeType(s, typeof(T), CultureInfo.InvariantCulture); } catch (Exception) { return @default; } } This code basically does what I want. However I would pretty much like to avoid the ugly try/catch here. I'm sure, that similar to TryParse, there is a modern method of rewriting this code without the catch-all. Could you suggest one?

    Read the article

  • Ping broadcast on Win XP SP3

    - by PaulH
    I'm trying to ping the broadcast address 255.255.255.255 on WinXP SP3. If I use the command line, I get host error: C:\>ping 255.255.255.255 Ping request could not find host 255.255.255.255. Please check the name and try again. If I try a C++ program using the iphlpapi, IcmpSendEcho() fails and GetLastError returns 11010 IP_REQ_TIMED_OUT. HANDLE h = ::IcmpCreateFile(); IPAddr broadcast = inet_addr( "255.255.255.255" ); BYTE payload[ 32 ] = { 0 }; IP_OPTION_INFORMATION option = { 255, 0, 0, 0, 0 }; // a buffer with room for 32 replies each containing the full payload std::vector< BYTE > replies( 32 * ( sizeof( ICMP_ECHO_REPLY ) + 32 ) ); DWORD res = ::IcmpSendEcho( h, broadcast, payload, sizeof( payload ), &option, &replies[ 0 ], replies.size(), 1000 ); ::IcmpCloseHandle( h ); I can ping the local broadcast 192.168.0.255 with no problem. What do I need to do to ping the global broadcast? Thanks, PaulH

    Read the article

  • checking mongo database for data

    - by user1647484
    I'm playing around with this tutorial that uses Sinatra, backbone.js, and mongodb for the database. It's my first time using mongo. As far as I understand it the app uses both local storage and a database. it has these routes for the database. For example, it has these routes get '/api/:thing' do DB.collection(params[:thing]).find.to_a.map{|t| from_bson_id(t)}.to_json end get '/api/:thing/:id' do from_bson_id(DB.collection(params[:thing]).find_one(to_bson_id(params[:id]))).to_json end post '/api/:thing' do oid = DB.collection(params[:thing]).insert(JSON.parse(request.body.read.to_s)) "{\"_id\": \"#{oid.to_s}\"}" end After turning the server off and then on, I could see in the server getting data from the database routes 127.0.0.1 - - [17/Sep/2012 08:21:58] "GET /api/todos HTTP/1.1" 200 430 0.0033 My question is, how can I check from within the mongo shell whether the data's in the database? I started the mongo shell ./bin/mongo I selected the database 'use mydb' and then looking at the docs (http://www.mongodb.org/display/DOCS/Tutorial) I tried commands such as > var cursor = db.things.find(); > while (cursor.hasNext()) printjson(cursor.next()); but they didn't return anything.

    Read the article

  • Data layer refactoring

    - by Joey
    I've taken control of some entity framework code and am looking to refactor it. Before I do, I'd like to check my thoughts are correct and I'm not missing the entity-framework way of doing things. Example 1 - Subquery vs Join Here we have a one-to-many between As and Bs. Apart from the code below being hard to read, is it also inefficient? from a in dataContext.As where ((from b in dataContext.Bs where b.Text.StartsWith(searchText) select b.AId).Distinct()).Contains(a.Id) select a Would it be better, for example, to use the join and do something like this? from a in dataContext.As where a.Bs.Any(b => b.Text.StartsWith(searchText)) select a Example 2 - Explicit Joins vs Navigation Here we have a one-to-many between As and Bs and a one-to-many between Bs and Cs. from a in dataContext.As join b in dataContext.Bs on b.AId equals a.Id join c in dataContext.Cs on c.BId equals b.Id where c.SomeValue equals searchValue select a Is there a good reason to use explicit joins rather than navigating through the data model? For example: from a in dataContext.As where a.Bs.Any(b => b.Cs.Any(c => c.SomeValue == searchValue) select a

    Read the article

  • Adding up fractions in PHP

    - by Gamemorize
    I would like to create a loop that keeps adding a set fraction, here in my example 1/3, and which later I can check against for matches with integer values. Obviously when php adds 1/3 + 1/3 + 1/3 the result is 0.9999999, so i thought I could use the occasional round to help me, but this isn't working either. The idea that I had would be that .333 + .333 becomes .666 and that if rounded that would become .667, then + .333 and the result is 1. However round only seems to work, for me, if the number of digits actually decreases. so round (0.666, 3) remains 0.666 <?php $denom = 3; $frac = 1/$denom; $frac = round($frac,3); $value = 0; $max =24; for($f = 1; $f <= $max; $f++){ echo "old value is now at ".$value.".<br/>"; $value = $value+$frac; echo "value is now at ".$value.".<br/>"; $value = round($value,3); echo "rounded value is now at ".$value.".<br/>"; $valueArray[$f] = $value; //and here for ease of testing.... if (($value==1)OR ($value==2)OR ($value==3)OR ($value==4)OR ($value==5)OR ($value==6)OR ($value==7)OR ($value==8)){ echo "match!<br/>"; }else{ echo "no match!<br/>"; } } ?> Am I going about this in a totally stupid way? Accuracy when the value is not an integer is not needed, just that it can == with integers.

    Read the article

  • Bruteforcing Blackberry PersistentStore?

    - by Haoest
    Hello, I am experimenting with Blackberry's Persistent Store, but I have gotten nowhere so far, which is good, I guess. So I have written a a short program that attempts iterator through 0 to a specific upper bound to search for persisted objects. Blackberry seems to intentionally slow the loop. Check this out: String result = "result: \n"; int ub = 3000; Date start = Calendar.getInstance().getTime(); for(int i=0; i<ub; i++){ PersistentObject o = PersistentStore.getPersistentObject(i); if (o.getContents() != null){ result += (String) o.getContents() + "\n"; } } result += "end result\n"; result += "from 0 to " + ub + " took " + (Calendar.getInstance().getTime().getTime() - start.getTime()) / 1000 + " seconds"; From 0 to 3000 took 20 seconds. Is this enough to conclude that brute-forcing is not a practical method to breach the Blackberry? In general, how secure is BB Persistent Store?

    Read the article

  • How can I solve this CSS links inheritance problem?

    - by Craig Whitley
    It's stumped me an I've tried a couple of things - then again I'm not very experienced so I may just be going about it the wrong way. Basically I want to have different link styles for both the navigation and the pagination. The #navigation styling is overriding my .pagination styling though, and it doesn't appear to matter if the pagination is a class or an ID. I've also tried putting !important in the pagination styling, but this then makes the navigation inherit the pagination (been using firebug to check the inheritance). #navigation a:active, a:link, a:visited, a, a:focus { color: #ffde2f; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 24px; text-decoration: none; } #navigation a:hover { color: #ffffff; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 24px; text-decoration: none; } .pagination a:active, a:link, a:visited, a, a:focus { color: #fff; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; font-size: 14px; text-decoration: none; } .pagination { color: #fff; font-size: 14px; font-family: Verdana, Geneva, Arial, Helvetica, sans-serif; }

    Read the article

  • Performing centralized authorization for multiple applications

    - by Vaibhav
    Here's a question that I have been wrestling with for a while. We have a situation wherein we have a number of applications that we have created. These have grown organically over a period of time. All of these applications have permissions code built into them that controls access to various parts of the application depending on whether the currently logged in user has the necessary permissions or not. Alongside these applications is a utility application which allows an administrator to map users to permissions for all applications - the way it works is that every application has code which reads this external database of the said utility application to check if the currently logged in user has the necessary permission or not. Now, the question is this. Should the user-permissions mapping information reside in and be owned by the applications themselves, or is it okay to have this information reside within an external entity/DB (as in this case the utility application's database). Part of me thinks that application permissions are very specific to the application context itself, so shouldn't be separated from the application itself. But I am not sure. Any comments?

    Read the article

  • Is this linear search implementation actually useful?

    - by Helper Method
    In Matters Computational I found this interesting linear search implementation (it's actually my Java implementation ;-)): public static int linearSearch(int[] a, int key) { int high = a.length - 1; int tmp = a[high]; // put a sentinel at the end of the array a[high] = key; int i = 0; while (a[i] != key) { i++; } // restore original value a[high] = tmp; if (i == high && key != tmp) { return NOT_CONTAINED; } return i; } It basically uses a sentinel, which is the searched for value, so that you always find the value and don't have to check for array boundaries. The last element is stored in a temp variable, and then the sentinel is placed at the last position. When the value is found (remember, it is always found due to the sentinel), the original element is restored and the index is checked if it represents the last index and is unequal to the searched for value. If that's the case, -1 (NOT_CONTAINED) is returned, otherwise the index. While I found this implementation really clever, I wonder if it is actually useful. For small arrays, it seems to be always slower, and for large arrays it only seems to be faster when the value is not found. Any ideas?

    Read the article

  • MySQL: Combining multiple where conditions

    - by Karl
    I'm working on a menu system that takes a url and then queries the db to build the menu. My menu table is: +---------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +---------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | node_id | int(11) | YES | | NULL | | | parent | int(11) | YES | | NULL | | | weight | int(11) | YES | | NULL | | | title | varchar(250) | YES | | NULL | | | alias | varchar(250) | YES | | NULL | | | exclude | int(11) | YES | | NULL | | +---------+--------------+------+-----+---------+----------------+ The relevant columns for my question are alias, parent and node_id. So for a url like: http://example.com/folder1/folder2/filename Alias would potentially = "filename", "folder1", "folder2" Parent = the node_id of the parent folder. What I know is how to split the url up into an array and check the alias for a match to each part. What I don't know is how to have it then filter by parent whose alias matches "folder2" and whose parent alias matches "folder1". I'm imagining a query like so: select * from menu where alias='filename' and where parent = node_id where alias='folder2' and parent = node_id where alias='folder1' Except I know that the above is wrong. I'm hoping this can be done in a single query. Thanks for any help in advance!

    Read the article

  • My Local Fileshare ClickOnce Update Is Not Working, Help?

    - by Soo
    I have a C# application that I'm trying to get to update automatically via ClickOnce. After publishing newer versions of software, I see the new versions in my publish folder, but when I open the application, it checks for updates, and does nothing (even though there are new files in the publish folder). What do I need in place for updates to be made automatically? Edit What version of Visual Studio are you using? Visual Studio 2008 Are you deploying the upgrades to the same location as the old version? They are being published to the same location (not sure about deployed) Is the installation URL the same? Have you incremented the version number? Yes In the Updates dialog reached by clicking the Updates button in the Publish page, do you have "The application should check for updates" checked? Yes Do you have "Before the application starts" selected? Yes How are you deploying the files? Not sure Are you copying them over to the file share or publishing the directly? Publishing directly

    Read the article

  • Repository layout and sparse checkouts

    - by chuanose
    My team is considering to move from Clearcase to Subversion and we are thinking of organising the repository like this: \trunk\project1 \trunk\project2 \trunk\project3 \trunk\staticlib1 \trunk\staticlib2 \trunk\staticlib3 \branches\.. \tags\.. The issue here is that we have lots of projects (1000+) and each project is a dll that links in several common static libraries. Therefore checking out everything in trunk is a non-starter as it will take way too long (~2 GB), and is unwieldy for branching. Using svn:externals to pull out relevant folders for each project doesn't seem ideal because it results in several working copies for each static library folder. We also cannot do an atomic commit if the changes span the project and some static libraries. Sparse checkouts sounds very suitable for this as we can write a script to pull out only the required directories. However when we want to merge changes from a branch back to the trunk we will need to first check out a full trunk. Wonder if there is some advice on 1) a better repository organization or 2) a way to merge over branch changes to a trunk working copy that is sparse?

    Read the article

  • Is this a safe way to release resources in Java?

    - by palto
    Usually when code needs some resource that needs to be released I see it done like this: InputStream in = null; try{ in = new FileInputStream("myfile.txt"); doSomethingWithStream(in); }finally{ if(in != null){ in.close(); } } What I don't like is that you have to initialize the variable to null and after that set it to another value and in the finally block check if the resource was initialized by checking if it is null. If it is not null, it needs to be released. I know I'm nitpicking, but I feel like this could be done cleaner. What I would like to do is this: InputStream in = new FileInputStream("myfile.txt"); try{ doSomethingWithStream(in); }finally{ in.close(); } To my eyes this looks almost as safe as the previous one. If resource initialization fails and it throws an exception, there's nothing to be done(since I didn't get the resource) so it doesn't have to be inside the try block. The only thing I'm worried is if there is some way(I'm not Java certified) that an exception or error can be thrown between operations? Even simpler example: Inputstream in = new FileInputStream("myfile.txt"); in.close(); Is there any way the stream would be left open that a try-finally block would prevent?

    Read the article

  • Javascript Anonymous Functions and Global Variables

    - by Jonathan Swift
    I thought I would try and be clever and create a Wait function of my own (I realise there are other ways to do this). So I wrote: var interval_id; var countdowntimer = 0; function Wait(wait_interval) { countdowntimer = wait_interval; interval_id = setInterval(function() { --countdowntimer <=0 ? clearInterval(interval_id) : null; }, 1000); do {} while (countdowntimer >= 0); } // Wait a bit: 5 secs Wait(5); This all works, except for the infinite looping. Upon inspection, if I take the While loop out, the anonymous function is entered 5 times, as expected. So clearly the global variable countdowntimer is decremented. However, if I check the value of countdowntimer, in the While loop, it never goes down. This is despite the fact that the anonymous function is being called whilst in the While loop! Clearly, somehow, there are two values of countdowntimer floating around, but why?

    Read the article

  • R: building a simple command line plotting tool/Capturing window close events

    - by user275455
    I am trying to use R within a script that will act as a simple command line plot tool. I.e. user pipes in a csv file and they get a plot. I can get to R fine and get the plot to display through various temp file machinations, but I have hit a roadblock. I cannot figure out how to get R to keep running until the users closes the window. If I plot and exit, the plot disappears immediately. If I plot and use some kind of infinite loop, the user cannot close the plot; he must exit by using an interrupt which I don't like. I see there is a getGraphicsEvent function, but it claims that the device is not supported (X11). Anyway, it doesn't appear to actually support an onClose event, only onMouseDown. Any ideas on how to solve this? edit: Thanks to Dirk for the advice to check out the tk interface. Here is the test code that works: require(tcltk) library(tkrplot) ##function to display plot, called by tkrplot and embedded in a window plotIt<-function(){ plot(x=1:10, y=1:10) } ##create top level window tt<-tktoplevel() ##variable to wait on like a condition variable, to be set by event handler done <- tclVar(0) ##bind to the window destroy event, set done variable when destroyed tkbind(tt,"",function() tclvalue(done) <- 1) ##Have tkrplot embed the plot window, then realize it with tkgrid tkgrid(tkrplot(tt,plotIt)) ##wait until done is true tkwait.variable(done)

    Read the article

< Previous Page | 718 719 720 721 722 723 724 725 726 727 728 729  | Next Page >