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  • Programmatically Update UITableView in Response to Button Press

    - by Kyle Begeman
    I have a completely custom view that holds a UITableView and a Custom Tab Bar (basically a UIView that contains 6 UIButtons). I am loading data from a plist file, and then I am sorting the data into multiple arrays based on categories (an array for misc items, and array for mail items, etc.) Each button in the tab bar represents a category, and when I press the button I call the custom function "miscSelected" and so on. How can I have the table view completely reload and then display the tableview based on the array selected (select the misc category and the tableview clears itself and loads the misc array data, same for any other category)? The method I have experimented with is created and NSString named "selection" and then in each button function I set selected to equal whatever section I am selecting. In my cellForRoxAtIndexPath method I have this: if ([self.selection isEqualToString:@"All Items"]) { NSArray *mainDataArray = [NSArray arrayWithContentsOfFile:self.plistFile]; NSSortDescriptor *brandDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name" ascending:YES]; NSArray *sortDescriptors = [NSArray arrayWithObject:brandDescriptor]; self.sortedData = [mainDataArray sortedArrayUsingDescriptors:sortDescriptors]; } else if ([self.selection isEqualToString:@"Misc Items"]){ self.sortedData = [NSArray arrayWithContentsOfFile:self.plistFile]; } cell.itemTitle.text = [[self.sortedData objectAtIndex:indexPath.row] objectForKey:@"name"]; For the sake of example and testing I am simply displaying the same data, just one button displays it in alphabetical order and the other does not. This code works only when I start to scroll down and back up, but it does not actually update on button press. Calling myTable reloadData does not do anything either. Any help would be great, thanks!

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  • MemoryStream instance timing help

    - by rod
    Hi All, Is it ok to instance a MemoryStream at the top of my method, do a bunch of stuff to it, and then use it? For instance: public static byte[] TestCode() { MemoryStream m = new MemoryStream(); ... ... whole bunch of stuff in between ... ... //finally using(m) { return m.ToArray(); } } Updated code public static byte[] GetSamplePDF() { using (MemoryStream m = new MemoryStream()) { Document document = new Document(); PdfWriter.GetInstance(document, m); document.Open(); PopulateTheDocument(document); document.Close(); return m.ToArray(); } } private static void PopulateTheDocument(Document document) { Table aTable = new Table(2, 2); aTable.AddCell("0.0"); aTable.AddCell("0.1"); aTable.AddCell("1.0"); aTable.AddCell("1.1"); document.Add(aTable); for (int i = 0; i < 20; i++) { document.Add(new Phrase("Hello World, Hello Sun, Hello Moon, Hello Stars, Hello Sea, Hello Land, Hello People. ")); } } My point was to try to reuse building the byte code. In other words, build up any kind of document and then send it to TestCode() method.

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  • Multiple forms + HAML + jQuery + Javascript submit

    - by Jay Godse
    Hi. I have a HAML page that lists some links to delete "things" that looks like this %div %a.form_submit Delete Thing 1 %form{:href=>"#", :id=>'comment_1', :method=>'post', :action=>'/thing/delete'} %input{:type=>'hidden', :name=>'thingid', :value=>'1'} %input{:type=>'submit', style='display:none'} %div %a.form_submit Delete Thing 22 %form{:href=>"#", :id=>'comment_22', :method=>'post', :action=>'/thing/delete'} %input{:type=>'hidden', :name=>'thingid', :value=>'22'} %input{:type=>'submit', style='display:none'} The intention is to have a link "Delete XX" which will delete something specific. A page could have a number of these links, and each link is for a specific "thing". I also have a piece of (unobtrusive) jQuery javascript that adds a click handler to each form as follows: $('a.form_submit').click(function(event) { $('form').submit(); event.preventDefauilt(); }); This works when there is one form on a page. However, if I have more than one form on a page, how do I ensure that clicking "Delete Thing 1" will trigger a submit() event only on the form with id='comment_1'?

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  • Error in Android's clearCheck() for RadioGroup?

    - by Manuel R. Ciosici
    I'm having an issue with RadioGroup's clearChecked(). I'm displaying a multiple choice question to the user and after the user selects an answer I check the answer, give him some feedback and then move to the next question. In the process of moving to the next question I clearCheck on the RadioGroup. Can anyone explain to me why the onCheckedChanged method is called 3 times? Once when the change actually occurs (with the user changes), once when I clearCheck(with -1 as the selected id) and once in between (with the user changes again)? As far as I could tell the second trigger is provoked by clearCheck. Code below: private void checkAnswer(RadioGroup group, int checkedId){ // this makes sure it doesn't blow up when the check is cleared // also we don't check the answer when there is no answer if (checkedId == -1) return; if (group.getCheckedRadioButtonId() == -1) return; // check if correct answer if (checkedId == validAnswerId){ score++; this.giveFeedBack(feedBackType.GOOD); } else { this.giveFeedBack(feedBackType.BAD); } // allow for user to see feedback and move to next question h.postDelayed(this, 800); } private void changeToQuestion(int questionNumber){ if (questionNumber >= this.questionSet.size()){ // means we are past the question set // we're going to the score activity this.goToScoreActivity(); return; } //clearing the check gr.clearCheck(); // give change the feedback back to question imgFeedback.setImageResource(R.drawable.question_mark); //OTHER CODE HERE } and the run method looks like this public void run() { questionNumber++; changeToQuestion(questionNumber); }

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  • Detect modification of variable at runtime in C/C++

    - by YuppieNetworking
    Hello, I am developing a library in C++ where users/programmer will extend a class BaseClass that has a method initArray. This method should be implemented by the user/programmer and it should normally initialize all elements of the array m_arr. Here is a snipplet, modified to this example: class BaseClass { public: BaseClass(int n) { m_arr = new double[n]; size = n; }; virtual ~BaseClass(); int size; double* m_arr; virtual int initArray(); }; Sometimes, the user/programmer implements a initArray that does not initialize some elements of m_arr. What I would like is to create a function in my library that checks if initArray did initialize all elements of m_arr. This function should be called by a sanity-check rutine at runtime. My question: is it possible to detect changes on this array? I can only think of initializing the array with some invalid values (like NaN or Inf), call initArray and check that all values have changed. Thanks for your ideas, David

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  • Best way to run multiple queries per second on database, performance wise?

    - by Michael Joell
    I am currently using Java to insert and update data multiple times per second. Never having used databases with Java, I am not sure what is required, and how to get the best performance. I currently have a method for each type of query I need to do (for example, update a row in a database). I also have a method to create the database connection. Below is my simplified code. public static void addOneForUserInChannel(String channel, String username) throws SQLException { Connection dbConnection = null; PreparedStatement ps = null; String updateSQL = "UPDATE " + channel + "_count SET messages = messages + 1 WHERE username = ?"; try { dbConnection = getDBConnection(); ps = dbConnection.prepareStatement(updateSQL); ps.setString(1, username); ps.executeUpdate(); } catch(SQLException e) { System.out.println(e.getMessage()); } finally { if(ps != null) { ps.close(); } if(dbConnection != null) { dbConnection.close(); } } } And my DB connection private static Connection getDBConnection() { Connection dbConnection = null; try { Class.forName(DB_DRIVER); } catch (ClassNotFoundException e) { System.out.println(e.getMessage()); } try { dbConnection = DriverManager.getConnection(DB_CONNECTION, DB_USER,DB_PASSWORD); return dbConnection; } catch (SQLException e) { System.out.println(e.getMessage()); } return dbConnection; } This seems to be working fine for now, with about 1-2 queries per second, but I am worried that once I expand and it is running many more, I might have some issues. My questions: Is there a way to have a persistent database connection throughout the entire run time of the process? If so, should I do this? Are there any other optimizations that I should do to help with performance? Thanks

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  • Interpreting item click in ListView

    - by Matt Huggins
    I'm working on my first Android project, and I created a menu via the XML method. My activity is pretty basic, in that it loads the main layout (containing a ListView with my String array of options). Here's the code inside my Activity: public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); // allow stuff to happen when a list item is clicked ListView ls = (ListView)findViewById(R.id.menu); ls.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { // @todo } }); } Within the onItemClick callback handler, I'd like to check which item was clicked, and load a new menu based upon that. Question 1: How do I go about figuring out which item was clicked? I can't find any straightforward examples on retrieving/testing the id value of the clicked item. Question 2: Once I have the id value, I assume I can just call the setContentView method again to change to another layout containing my new menu. Is that correct?

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  • Is it OK to set state within Event Raising methods?

    - by Greg
    I ran across this pattern in the code of a library I'm using. It sets state within the event raising method, but only if the event is not null. protected virtual void OnMyEvent(EventArgs e) { if(MyEvent != null) { State = "Executing"; // Only sets state if MyEvent != null. MyEvent(this,e); } } Which means that the state is not set when overriding the method: protected override void OnMyEvent(EventArgs e) { base.OnMyEvent(e); Debug.Assert( State == "Executing" ); // This fails } but is only set when handling the event: foo.MyEvent += (o, args) => Debug.Assert(State == "Executing"); // This passes Setting state within the if(MyEvent != null) seems like bad form, but I've checked the Event Design Guidelines and it doesn't mention this. Do you think this code is incorrect? If so, why? (Reference to design guidelines would be helpful). Edit for Context: It's a Control, I'm trying to create subclass of it, and the state that it's setting is calling EnsureChildControls() conditionally based upon there being an event handler. I can call EnsureChildControls() myself, but I consider that something of a hack.

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  • std::bad_cast from parent to child?

    - by polyglot
    For simplicity, class Parent {} class Child1 : Parent {} class Child2 : Parent {} Elsewhere, I created instances of Child1 and Child2 and store it in same vector under Parent: // . . . in .h file, for example vector<Parent> vector_of_parent; // . . . in one particular method Child1 c1(); Child2 c2(); vector_of_parent.push_back(c1); vector_of_parent.push_back(c2); // . . . Then in another method which has access to vector_of_parent, I tried void doSomething(Parent& some_child) { // wrapped in a try block somehow... Child1& c = dynamic_cast<Child1&> some_child; // do something if the cast is successful } void otherMethod() { doSomething(vector_of_parent.at(0)); // vector_of_parent.at(0) is a Child1 } Why is there a std:bad_cast when I call otherMethod()?

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  • wx_ref and custom wx_object's

    - by Iogann
    Hi! I am developing MDI application with help of wxErlang. I have a parent frame, implemented as wx_object: -module(main_frame). -export([new/0, init/1, handle_call/3, handle_event/2, terminate/2]). -behaviour(wx_object). .... And I have a child frame, implemented as wx_object too: module(child_frame). -export([new/2, init/1, handle_call/3, handle_event/2, terminate/2]). -export([save/1]). -behaviour(wx_object). % some public API method save(Frame) -> wx_object:call(Frame, save). .... I want to call save/1 for an active child frame from the parent frame. There is my code: ActiveChild = wxMDIParentFrame:getActiveChild(Frame), case wx:is_null(ActiveChild) of false - child_frame:save(ActiveChild); _ - ignore end This code fails because ActiveChild is #wx_ref{} with state=[], but wx_object:call/2 needs #wx_ref{} where state is set to the pid of the process which we call. What is the right method to do this? I thought only to store a list of all created child frames with its pids in the parent frame and search the pid in this list, but this is ugly.

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  • Java Generics error when implementing Hibernate message interpolator

    - by Jayaprakash
    Framework: Spring, Hibernate. O/S: Windows I am trying to implement hibernate's Custom message interpolator following the direction of this Link. When implementing the below class, it gives an error "Cannot make a static reference to the non-static type Locale". public class ClientLocaleThreadLocal<Locale> { private static ThreadLocal tLocal = new ThreadLocal(); public static void set(Locale locale) { tLocal.set(locale); } public static Locale get() { return tLocal.get(); } public static void remove() { tLocal.remove(); } } As I do not know generics enough, not sure how is being used by TimeFilter class below and the purpose of definition in the above class. public class TimerFilter implements Filter { public void destroy() { } public void doFilter(ServletRequest req, ServletResponse res, FilterChain filterChain) throws IOException, ServletException { try { ClientLocaleThreadLocal.set(req.getLocale()); filterChain.doFilter(req, res); }finally { ClientLocaleThreadLocal.remove(); } } public void init(FilterConfig arg0) throws ServletException { } } Will doing the following be okay? Change static method/field in ClientLocaleThreadLocal to non-static method/fields In TimeFilter, set locale by instantiating new object as below. new ClientLocaleThreadLocal().set(req.getLocale()) Thanks for your help in advance

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  • java.lang.ClassNotFoundException: com.mysql.jdbc.Driver When run jar file

    - by user1024858
    Hi all, Connection conn = null; String url = "jdbc:mysql://localhost:3306/"; String dbName = "test"; String driver = "com.mysql.jdbc.Driver"; String userName = "root"; String password = "admin"; try { Class.forName(driver).newInstance(); conn = DriverManager.getConnection(url+dbName,userName,password); System.out.println("Connected to the database"); conn.close(); System.out.println("Disconnected from database"); } catch (Exception e) { e.printStackTrace();} I run in eclipse it's ok, but i built to jar file and run on command line java -jar Test.jar i get this error: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver at java.net.URLClassLoader$1.run(Unknown Source) at java.net.URLClassLoader$1.run(Unknown Source) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Unknown Source) Please help me how to fix it. Thanks!!!

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  • Bitmap issue in Samsung Galaxy S3

    - by user1531240
    I wrote a method to change Bitmap from camera shot : public Bitmap bitmapChange(Bitmap bm) { /* get original image size */ int w = bm.getWidth(); int h = bm.getHeight(); /* check the image's orientation */ float scale = w / h; if(scale < 1) { /* if the orientation is portrait then scaled and show on the screen*/ float scaleWidth = (float) 90 / (float) w; float scaleHeight = (float) 130 / (float) h; Matrix mtx = new Matrix(); mtx.postScale(scaleWidth, scaleHeight); Bitmap rotatedBMP = Bitmap.createBitmap(bm, 0, 0, w, h, mtx, true); return rotatedBMP; } else { /* if the orientation is landscape then rotate 90 */ float scaleWidth = (float) 130 / (float) w; float scaleHeight = (float) 90 / (float) h; Matrix mtx = new Matrix(); mtx.postScale(scaleWidth, scaleHeight); mtx.postRotate(90); Bitmap rotatedBMP = Bitmap.createBitmap(bm, 0, 0, w, h, mtx, true); return rotatedBMP; } } It works fine in another Android device, even Galaxy Nexus but in Samsung Galaxy S3, the scaled image doesn't show on screen. I tried to mark the bitmapChange method , let it show the original size Bitmap on screen but S3 also show nothing on screen. The information of variables in eclipse is here. The information of sony xperia is here. xperia and other device is working fine.

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  • Creating mock Objects in PHP unit

    - by Mike
    Hi, I've searched but can't quite find what I'm looking for and the manual isn't much help in this respect. I'm fairly new to unit testing, so not sure if I'm on the right track at all. Anyway, onto the question. I have a class: <?php class testClass { public function doSomething($array_of_stuff) { return AnotherClass::returnRandomElement($array_of_stuff); } } ?> Now, clearly I want the AnotherClass::returnRandomElement($array_of_stuff); to return the same thing every time. My question is, in my unit test, how do I mockup this object? I've tried adding the AnotherClass to the top of the test file, but when I want to test AnotherClass I get the "Cannot redeclare class" error. I think I understand factory classes, but I'm not sure how I would apply that in this instance. Would I need to write an entirely seperate AnotherClass class which contained test data and then use the Factory class to load that instead of the real AnotherClass? Or is using the Factory pattern just a red herring. I tried this: $RedirectUtils_stub = $this->getMockForAbstractClass('RedirectUtils'); $o1 = new stdClass(); $o1->id = 2; $o1->test_id = 2; $o1->weight = 60; $o1->data = "http://www.google.com/?ffdfd=fdfdfdfd?route=1"; $RedirectUtils_stub->expects($this->any()) ->method('chooseRandomRoot') ->will($this->returnValue($o1)); $RedirectUtils_stub->expects($this->any()) ->method('decodeQueryString') ->will($this->returnValue(array())); in the setUp() function, but these stubs are ignored and I can't work out whether it's something I'm doing wrong, or the way I'm accessing the AnotherClass methods. Help! This is driving me nuts.

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  • C++ Dynamic object construction

    - by Rajesh Subramanian
    I have a base class, class Msg { ParseMsg() { ParseMsgData(); ParseTrailer(); } virtual void ParseMsgData() = 0; ParseTrailer(); }; and derived classes, class InitiateMsg { void ParseMsgData() { ... } }; class ReadOperationMsg { void ParseMsgData() { ... } }; class WriteOperationMsg { void ParseMsgData() { ... } }; and the scenario is below, void UsageFunction(string data) { Msg* msg = ParseHeader(data); ParseMsg } Msg* ParseHeader(string data) { Msg *msg = NULL; .... switch() { case 1: msg = new InitiateMsg(); break; case 2: msg = new ReadOperationMsg{(); break; case 3: msg = new WriteOperationMsg{(); break; .... } return msg; } based on the data ParseHeader method will decide which object has to be created, So I have implemented ParseHeader function outside the class where I am using. How can I make the ParseHeader function inside the Msg class and then use it? In C# the same is achieved by defining ParseHeader method as static with in class and use it from outside,

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  • C++ creating generic template function specialisations

    - by Fire Lancer
    I know how to specialise a template function, however what I want to do here is specialise a function for all types which have a given method, eg: template<typename T> void foo(){...} template<typename T, if_exists(T::bar)>void foo(){...}//always use this one if the method T::bar exists T::bar in my classes is static and has different return types. I tried doing this by having an empty base class ("class HasBar{};") for my classes to derive from and using boost::enable_if with boost::is_base_of on my "specialised" version. However the problem then is that for classes that do have bar, the compiler cant resolve which one to use :(. template<typename T> typename boost::enable_if<boost::is_base_of(HasBar, T>, void>::type f() {...} I know that I could use boost::disable_if on the "normal" version, however I do not control the normal version (its provided by a third party library and its expected for specialisations to be made, I just don't really want to make explicit specialisations for my 20 or so classes), nor do I have that much control over the code using these functions, just the classes implementing T::bar and the function that uses it. Is there some way to tell the compiler to "always use this version if possible no matter what" without altering the other versions?

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  • Deserialization of a DataSet... deal with column name changes? how to migrate data from one column to another?

    - by Brian Kennedy
    So, we wanted to slightly generalize a couple columns in our typed dataset... basically dropped a foreign key constraint and then wanted to change a couple column names to better reflect their new state. All that is easy. The problem is that our users may have serialized out the old version of the DataSet as XML. We want to be able to read those old XML files and deserialize them into the revised DataSet. It seems that would be a fairly common desire... but I haven't yet figured out the right thing to search the internet for. One possible solution would seem to be some way to give a DataColumn an alias or alternate name such that when it reads the old column name, it knows that data can be read into the column with the new column name. I can find no support for any such thing. Another approach would seem to be an "after deserialization" method of some sort... so, I would let it read in the old column values into a normal DataColumn with that name, and then in the "after deserialization" method I would just move the data from the obsolete column into the new column, and then delete the old columns. That would seem to generalize to many other situations... and having such events or hooks is pretty common in ADO.NET. But I have looked for such a hook and haven't yet found it. If no "after deserialization" hook, it would seem I ought to be able to override ReadXml or ReadXmlSerializable methods to call the base and then do my "after" stuff to fix up old data into new. But it does not appear that is possible. Soooo, I have to think backward compatibility with old serialized DataSets and simple data migration would be a well-solved problem... so, trying to reinvent that wheel seems silly. But so far, I haven't seemed to find any documentation on doing those things. Suggestions? What is best practice for this?

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  • When using a repository is it possible for a type to return a Func that the repository uses to test for existing entities?

    - by Scott Rickman
    For example given a Factory with a method public static T Save<T>(T item) where T : Base, new() { /* item.Id == Guid.Empty therefore item is new */ if (item.Id == Guid.Empty && repository.GetAll<T>(t => t.Name == item.Name)) { throw new Exception("Name is not unique"); } } how do I create a property of Base (say MustNotAlreadyExist) so that I can change the method above to public static T Save<T>(T item) where T : Base, new() { /* item.Id == Guid.Empty therefore item is new */ if (item.Id == Guid.Empty && repository.GetAll<T>(t.MustNotAlreadyExist)) { throw new Exception("Name is not unique"); } } public class Base { ... public virtual Expression<Func<T, bool>> MustNotAlreadyExist() { return (b => b.Name == name); /* <- this clearly doesn't work */ } } and then how can I override MustNotAlreadyExist in Account : Base public class Account : Base { ... public override Expression<Func<T, bool>> MustNotAlreadyExist() { return (b => b.Name == name && b.AccountCode == accountCode); /* <- this doesn't work */ } ... }

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  • Objective C iPhone performance issue

    - by Asad Khan
    Ok guys I am developing an iPhone app I have a Model class which follows a Singleton design pattern. Now I have an NSArray in it which is initialized to around some 1000 NSStrings in the init method. Now I need to use this data in some view controller. so I import Model.h, I create an array of NSString objects in view controller & set the data to it. But now the problem is that now I have 2000 NSStrings currently allocated, which I believe is not a good thing on iPhone due to memory considerations. releasing model object wont help because I've overrided release method to release nothing according to the pattern & I cannot change the design now because now a lot of code works on the assumption of model being a singleton. & in future maybe the initial NSStrings may grow to 2000 or even more & then I'll have 4000 NSStrings allocated at one time .... I am a little confused on how to go about it any suggestions

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  • Trouble with go tour crawler exercise

    - by David Mason
    I'm going through the go tour and I feel like I have a pretty good understanding of the language except for concurrency. On slide 71 there is an exercise that asks the reader to parallelize a web crawler (and to make it not cover repeats but I haven't gotten there yet.) Here is what I have so far: func Crawl(url string, depth int, fetcher Fetcher, ch chan string) { if depth <= 0 { return } body, urls, err := fetcher.Fetch(url) if err != nil { ch <- fmt.Sprintln(err) return } ch <- fmt.Sprintf("found: %s %q\n", url, body) for _, u := range urls { go Crawl(u, depth-1, fetcher, ch) } } func main() { ch := make(chan string, 100) go Crawl("http://golang.org/", 4, fetcher, ch) for i := range ch { fmt.Println(i) } } The issue I have is where to put the close(ch) call. If I put a defer close(ch) somewhere in the Crawl method, then I end up writing to a closed channel in one of the spawned goroutines, since the method will finish execution before the spawned goroutines do. If I omit the call to close(ch), as is shown in my example code, the program deadlocks after all the goroutines finish executing but the main thread is still waiting on the channel in the for loop since the channel was never closed.

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  • Adapting pseudocode to java implementation for finding the longest word in a trie

    - by user1766888
    Referring to this question I asked: How to find the longest word in a trie? I'm having trouble implementing the pseudocode given in the answer. findLongest(trie): //first do a BFS and find the "last node" queue <- [] queue.add(trie.root) last <- nil map <- empty map while (not queue.empty()): curr <- queue.pop() for each son of curr: queue.add(son) map.put(son,curr) //marking curr as the parent of son last <- curr //in here, last indicate the leaf of the longest word //Now, go up the trie and find the actual path/string curr <- last str = "" while (curr != nil): str = curr + str //we go from end to start curr = map.get(curr) return str This is what I have for my method public static String longestWord (DTN d) { Queue<DTN> holding = new ArrayQueue<DTN>(); holding.add(d); DTN last = null; Map<DTN,DTN> test = new ArrayMap<DTN,DTN>(); DTN curr; while (!holding.isEmpty()) { curr = holding.remove(); for (Map.Entry<String, DTN> e : curr.children.entries()) { holding.add(curr.children.get(e)); test.put(curr.children.get(e), curr); } last = curr; } curr = last; String str = ""; while (curr != null) { str = curr + str; curr = test.get(curr); } return str; } I'm getting a NullPointerException at: for (Map.Entry<String, DTN> e : curr.children.entries()) How can I find and fix the cause of the NullPointerException of the method so that it returns the longest word in a trie?

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  • Same random numbers from instantiated class

    - by user1797202
    I'm learning C# and created a class within my program that holds a random number generator: class RandomNumberGenerator { Random RNG = new Random(); // A bunch of methods that use random numbers are in here } Inside this class are a few methods that use the RNG. Data gets sent here from other parts of the program, gets processed, then gets returned. One of the methods does the following: // Method works something like this int Value1 = RNG.Next(x, y); int Value2 = RNG.Next(x, y); int Value3 = RNG.Next(x, y); The x, y values are to be sent here from another class. So, I have to create an instance of the RandomNumberGenerator within that class so I can call its methods and pass the x and y values to it. class DoStuff { RandomNumberGenerator Randomizer = new RandomNumberGenerator // Here I call a bunch of Randomizer methods that give me values I need } The problem in the above method is that I get the same numbers every time for all three values. I'm not sure if it's because they're so close together and Randomizer's seed value hasn't had time to change or if I'm doing something wrong when I create a new instance of the RandomNumberGenerator class. I've gone through a bunch of answers on here already and typically problems like this are due to people creating many new Random objects when they run methods (thus setting the seed for all of them to the same value), but the only new Random object I create is within the RandomNumberGenerator class. I then instantiate that once within the other class so I can pass it data and use its methods. Why is this happening and how would I fix this?

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  • REST design: what verb and resource name to use for a filtering service

    - by kabaros
    I am developing a cleanup/filtering service that has a method that receives a list of objects serialized in xml, and apply some filtering rules to return a subset of those objects. In a REST-ful service, what verb shall I use for such a method? I thought that GET is a natural choice, but I have to put the serialized XML in the body of the request which works but feels incorrect. The other verbs don't seem to fit semantically. What is a good way to define that Service interface? Naming the resource /Cleanup or /Filter seems weird mainly because in the examples I see online, it is always a name rather than a verb being used for resource name. Am I right to feel that REST services are better suited for CRUD operations and you start bending the rules in situations like this service? If yes, am I then making a wrong architectural choice. I've pushed to develop this service in REST-ful style (as opposed to SOAP) for simplicity, but such awkward cases happen a lot and make me feel like I am missing something. Either choosing REST where it shouldn't be used or may be over-thinking some stuff that doesn't really matter? In that case, what really matters?

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  • Linked List Inserting strings in alphabetical order

    - by user69514
    I have a linked list where each node contains a string and a count. my insert method needs to inset a new node in alphabetical order based on the string. if there is a node with the same string, then i increment the count. the problem is that my method is not inserting in alphabetical order public Node findIsertionPoint(Node head, Node node){ if( head == null) return null; Node curr = head; while( curr != null){ if( curr.getValue().compareTo(node.getValue()) == 0) return curr; else if( curr.getNext() == null || curr.getNext().getValue().compareTo(node.getValue()) > 0) return curr; else curr = curr.getNext(); } return null; } public void insert(Node node){ Node newNode = node; Node insertPoint = this.findIsertionPoint(this.head, node); if( insertPoint == null) this.head = newNode; else{ if( insertPoint.getValue().compareTo(node.getValue()) == 0) insertPoint.getItem().incrementCount(); else{ newNode.setNext(insertPoint.getNext()); insertPoint.setNext(newNode); } } count++; }

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  • Implementations details of drag and drop of file path in cocoa.

    - by foo
    Hi, I'm trying to get a part of my window to react to drag and drop. In this case to copy the file path to the file being dropped on the view. I have looked over some documentation but I still have some problems to see exactly where I should implement my methods for drag and drop. I have seen some examples but almost all of them assumes that I want to drop an image on the view. I'm pretty new to cocoa and Xcode so, I have some problems with seeing the exact relation between interface builder and the generated code. I have created a subclass to NSView, called drop zone like this: #import <Cocoa/Cocoa.h> @interface dropZone : NSView { } @end I then use an NSRect to color it grey like this: #import "dropZone.h" @implementation dropZone - (void)drawRect:(NSRect)rect { NSRect bounds = [self bounds]; [[NSColor grayColor] set]; [NSBezierPath fillRect:bounds]; } @end I then drag this class to my window in interface builder. But I will need to implement the registerForDraggingTypes method, but where? I have also seen a convenience method in the Apple docs for file paths like this: dragFile:fromRect:slideBack:event: that might work.

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