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  • TableView Cells unresponsive

    - by John Donovan
    I have a TableView and I wish to be able to press several cells one after the other and have messages appear. At the moment the cells are often unresponsive. I found some coed for a similar problem someone was kind enough to post, however, although he claimed it worked 100% it doesn't work for me. The app won't even build. Here's the code: -(UIView*) hitTest:(CGPoint)point withEvent:(UIEvent*)event { // check to see if the hit is in this table view if ([self pointInside:point withEvent:event]) { UITableViewCell* newCell = nil; // hit is in this table view, find out // which cell it is in (if any) for (UITableViewCell* aCell in self.visibleCells) { if ([aCell pointInside:[self convertPoint:point toView:aCell] withEvent:nil]) { newCell = aCell; break; } } // if it touched a different cell, tell the previous cell to resign // this gives it a chance to hide the keyboard or date picker or whatever if (newCell != activeCell) { [activeCell resignFirstResponder]; self.activeCell = newCell; // may be nil } } // return the super's hitTest result return [super hitTest:point withEvent:event]; } With this code I get this warning: that my viewController may not respond to pointsInside:withEvent (it's a TableViewController). I also get some faults: request for member 'visibleCells' in something not a structure or a union. incompatible type for argument 1 of pointInsideWithEvent, expression does not have a valid object type and similar. I must admit I'm not so good at reading other people's code but I was wondering whether the problems here are obvious and if so if anyone could give me a pointer it would be greatly appreciated.

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  • Loading a javascript library in javax.script?

    - by Shane
    I want to run Protovis javascript from Java and get the evaluated SVG code. I am using javax.script.* to run the Javascript: public static void EvalScript() throws Exception { ScriptEngineManager factory = new ScriptEngineManager(); ScriptEngine engine = factory.getEngineByName("JavaScript"); Object result = engine.eval("var vis = new pv.Panel().width(300).height(300) .add (pv.Line).data ([1,0.5, 0.1, 0.01, 0.001, 0.3, 0.2,0.1,1]) .left (function () { return this.index * 30; }) .bottom (function (d) { return d * 250; }); vis.root.render(); vis.scene[0].canvas.innerHTML;"); System.out.println(result); } This would complain because I never loaded Protovis itself, as would ordinarily be done with <script type="text/javascript" src="../protovis-r3.1.0.js"></script> Is there a good way, short of sourcing in the full Javascript into the eval() command, of loading a library when running Javascript through javax.script? (Incidentally, I know of examples that use Rhino to do this from the Google discussion group.)

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  • Entity Framework with ASP.NET MVC. Updating entity problem

    - by Kitaly
    Hi people. I'm trying to update an entity and its related entities as well. For instance, I have a class Car with a property Category and I want to change its Category. So, I have the following methods in the Controller: public ActionResult Edit(int id) { var categories = context.Categories.ToList(); ViewData["categories"] = new SelectList(categories, "Id", "Name"); var car = context.Cars.Where(c => c.Id == id).First(); return PartialView("Form", car); } [AcceptVerbs(HttpVerbs.Post)] public ActionResult Edit(Car car) { var category = context.Categories.Where(c => c.Id == car.Category.Id).First(); car.Category = category; context.UpdateCar(car); context.SaveChanges(); return RedirectToAction("Index"); } The UpdateCar method, in ObjectContext class, follows: public void UpdateCar(Car car) { var attachedCar = Cars.Where(c => c.Id == car.Id).First(); ApplyItemUpdates(attachedCar, car); } private void ApplyItemUpdates(EntityObject originalItem, EntityObject updatedItem) { try { ApplyPropertyChanges(originalItem.EntityKey.EntitySetName, updatedItem); ApplyReferencePropertyChanges(updatedItem, originalItem); } catch (InvalidOperationException ex) { Console.WriteLine(ex.ToString()); } } public void ApplyReferencePropertyChanges(IEntityWithRelationships newEntity, IEntityWithRelationships oldEntity) { foreach (var relatedEnd in oldEntity.RelationshipManager.GetAllRelatedEnds()) { var oldRef = relatedEnd as EntityReference; if (oldRef != null) { var newRef = newEntity.RelationshipManager.GetRelatedEnd(oldRef.RelationshipName, oldRef.TargetRoleName) as EntityReference; oldRef.EntityKey = newRef.EntityKey; } } } The problem is that when I set the Category property after the POST in my controller, the entity state changes to Added instead of remaining as Detached. How can I update one-to-one relationship with Entity Framework and ASP.NET MVC without setting all the properties, one by one like this post?

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  • How does one properly redefine self while avoiding the "Multiple methods named ..." warning?

    - by Elise van Looij
    In Apple's The Objective-C Programming Language: Defining a Class the section named "Redifining self" recommends that that class methods allocate and return instances use 'self' only to allocate an instance and then refer only to that instance. Thus, I have a number of subclasses, that have class methods along the lines of: + (id)scrollViewWithFrame: (NSRect)rectFrame { id newInstance = [[[self alloc] initWithFrame:rectFrame] autorelease]; [newInstance setHasHorizontalScroller: YES]; [newInstance setHasVerticalScroller: YES]; [newInstance setBorderType: NSNoBorder]; [newInstance setAutoresizingMask: (NSViewWidthSizable | NSViewHeightSizable)]; return newInstance; } The above is, of course, a subclass of NSScrollView. Unfortunately, Xcode 3.x all these NSView subclasses now raise warnings: "Warning: Multiple methods named '-setAutoresizingMask' found". I believe it has something to do with GCC 4.2, the settings of which I have not changed. The warning is correct, of course, since NSView and its various subclasses all implement setAutoresizingMask, but it is also unnecessary. Since they're only warnings, I ignore them but there is a risk that in between the thirty or so unnecessary ones, a really useful warning lurks which I simply don't see. So, what to do? I do want to adhere to good coding practices and I want to build warning-free apps -- how can I do both?

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  • Disable second dropdown menu before first is populated

    - by johnny-kessel
    I need to grey out the second jump box (Select a Subcategory) before the first (Choose a Category) has a valid selection ..Here is the current code.. thanks guys <script type="text/javascript"> \$j(document).ready(function() { \$j('.subf_dropdown').html($j('.subf_dropdown').html()); }); function chooseForum(f, name) { \$j.ajax({ url: 'index.php?autocom=cats&root=' + f, type: 'GET', timeout: 100000, error: function(){ alert('Oops something went wrong. Please try again'); }, success: function(xml){ \$j('.subf_dropdown').html("<optgroup label='Subcategories'> " + xml + " </optgroup>"); } }); } function newPostInForum(f) { if (f != "") { window.location = "http://www.xxx.co.za/?act=post&do=new_post&f=" + f; } } </script> <select name='f' class='f_dropdown' onchange="chooseForum(this.value, this); return false;"> <optgroup label="Choose a Category"> {$data} </optgroup> </select> <br /><br /> <select name='subf' class='subf_dropdown' onchange="newPostInForum(this.value); return false;"> <optgroup label="Subcategories"> <option value="" selected="selected">Select a Subcategory</option> </optgroup> </select>

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  • How to solve non-linear equations using python

    - by stars83clouds
    I have the following code: #!/usr/bin/env python from scipy.optimize import fsolve import math h = 6.634e-27 k = 1.38e-16 freq1 = 88633.9360e6 freq2 = 88631.8473e6 freq3 = 88630.4157e6 def J(freq,T): return (h*freq/k)/(math.exp(h*freq/(k*T))-1) def equations(x,y,z,w,a,b,c,d): f1 = a*(J(freq1,y)-J(freq1,2.73))*(1-math.exp(-a*z))-(J(freq2,x)-J(freq2,2.73))*(1-math.exp(-z)) f2 = b*(J(freq3,w)-J(freq3,2.73))*(1-math.exp(-b*z))-(J(freq2,x)-J(freq2,2.73))*(1-math.exp(-z)) f3 = c*(J(freq3,w)-J(freq3,2.73))*(1-math.exp(-b*z))-(J(freq1,y)-J(freq1,2.73))*(1-math.exp(-a*z)) f4 = d*(J((freq3+freq1)/2,(y+w)/2)-J((freq3+freq1)/2,2.73))-(J(freq2,x)-J(freq2,2.73))*(1-math.exp(-z)) return (f1,f2,f3,f4) So, I have defined the equations in the above code. However, I now wish to solve the above set of equations using fsolve or other alternative non-linear numerical routine. I tried the following syntax but with no avail: x,y,z,w = fsolve(equations, (1,1,1,1)) I keep getting the error that "x" is not defined. I am executing all commands at the command-line, since I have no idea how to run a batch of commands as above automatically in python. I welcome any advice on how to solve this.

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  • error : java.lang.String cannot be cast to coldfusion.cfc.CFCBeanProxy anyone know about this ?

    - by faheem
    Hi does anyone know about this error I get when I try to insert a foreign key value in my entry entity using cf9 Hibernate ? java.lang.ClassCastException: java.lang.String cannot be cast to coldfusion.cfc.CFCBeanProxy Root cause :org.hibernate.HibernateException: java.lang.ClassCastException: java.lang.String cannot be cast to coldfusion.cfc.CFCBeanProxy Below is the code for my entity object and then for my user object.. Is there anything wrong with this ? entry.cfc /** * Entries Object */ component output="false" persistent="true"{ property name="entry_id" fieldType="id" generator="uuid"; property name="entryBody" ormType="text"; property name="title" notnull="true" type="string"; property name="time" fieldtype="timestamp"; property name="isCompleted" ormType="boolean" dbdefault="0" default="false"; property name="userID" fieldtype="many-to-one" fkcolumn="userID" cfc="user"; Entry function init() output=false{ return this; } } user.cfc /** * Users Object */ component output="false" persistent="true"{ property name="userID" fieldType="id" generator="uuid"; property name="firstName" notnull="true" type="string"; property name="lastName" notnull="true" type="string"; property name="password" notnull="true" type="string"; property name="userType" notnull="true" type="string"; //property name="entry" fieldtype="one-to-many" type="array" fkcolumn="userID" cfc="entry"; User function init() output=false{ return this; } }

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  • problem getting info from a cookie with javascript

    - by Jason
    I am having an issue with my cookies and I can't figure it out. Basically I have it set up so it checks for the cookie to see if the user is logged in, and then displays either a welcome message or a login link. It works - except that instead of returning the persons name in the welcome message it just is blank where the name should be. The cookie is there, with all the appropriate info.. not sure what I am doing wrong. var itm = new Array(); itm[0] = findCookie("ui"); if (itm[0] == null) { document.write("<h2><a href='logreg.html'>Log In or Sign Up</a></h2>"); } else { var c1 = itm[0].indexOf(","); var c2 = itm[0].indexOf(",",c1); var c3 = itm[0].indexOf(",",c2); var gname = itm[0].substring(c2,c3); document.write("<h2>Welcome "+gname+"!</h2>"); } The findCookie function is.. function findCookie(val){ var cookie = null; var findVal = val + "="; var dc = document.cookie; if (dc.length > 0) { var start = dc.indexOf(findVal); if (start >= 0) { start += findVal.length; lastVal = dc.indexOf(";", start); if (lastVal == -1) { lastVal = dc.length; } cookie = (dc.substring(start, lastVal)); } else { return cookie; } } return cookie; }

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  • Visual Studio expression containing a term named "by" cannot be evaluated in the watch window

    - by Andrei Pana
    Consider my C++ code below: int _tmain(int argc, _TCHAR* argv[]) { int by = 10; printf("%d\n", by); int bx = 20; printf("%d\n", (by + bx)); return 0; } which works fine. The funny thing is with the "by" variable. If I try to add a watch for a simple expression that contains by, the result will be CXX0030: Error: expression cannot be evaluated. For example, on a breakpoint on return 0, if I add the following watches I get the results mentioned: by : 10 bx : 20 by + 5 : CXX0030: Error: expression cannot be evaluated bx + 5 : 25 by + bx : CXX0030: Error: expression cannot be evaluated (by) + bx : 30 by + (bx) : CXX0030: Error: expression cannot be evaluated bx + (by) : CXX0014: Error: missing operrand This happens on VS2010, VS2008 on multiple computers. So, more out of curiosity, what is happening with "by"? Is it some kind of strange operator? Why doesn't bx get the same treatment? (I've tried google on this but it is quite difficult to get some relevant hits with terms like "by")

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  • How does Subsonic handle connections?

    - by Quintin Par
    In Nhibernate you start a session by creating it during a BeginRequest and close at EndRequest public class Global: System.Web.HttpApplication { public static ISessionFactory SessionFactory = CreateSessionFactory(); protected static ISessionFactory CreateSessionFactory() { return new Configuration() .Configure(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "hibernate.cfg.xml")) .BuildSessionFactory(); } public static ISession CurrentSession { get{ return (ISession)HttpContext.Current.Items["current.session"]; } set { HttpContext.Current.Items["current.session"] = value; } } protected void Global() { BeginRequest += delegate { CurrentSession = SessionFactory.OpenSession(); }; EndRequest += delegate { if(CurrentSession != null) CurrentSession.Dispose(); }; } } What’s the equivalent in Subsonic? The way I understand, Nhibernate will close all the connections at endrequest. Reason: While trouble shooting some legacy code in a Subsonic project I get a lot of MySQL timeouts,suggesting that the code is not closing the connections MySql.Data.MySqlClient.MySqlException: error connecting: Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached. Generated: Tue, 11 Aug 2009 05:26:05 GMT System.Web.HttpUnhandledException: Exception of type 'System.Web.HttpUnhandledException' was thrown. --- MySql.Data.MySqlClient.MySqlException: error connecting: Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached. at MySql.Data.MySqlClient.MySqlPool.GetConnection() at MySql.Data.MySqlClient.MySqlConnection.Open() at SubSonic.MySqlDataProvider.CreateConnection(String newConnectionString) at SubSonic.MySqlDataProvider.CreateConnection() at SubSonic.AutomaticConnectionScope..ctor(DataProvider provider) at SubSonic.MySqlDataProvider.GetReader(QueryCommand qry) at SubSonic.DataService.GetReader(QueryCommand cmd) at SubSonic.ReadOnlyRecord`1.LoadByParam(String columnName, Object paramValue) My connection string is as follows <connectionStrings> <add name="xx" connectionString="Data Source=xx.net; Port=3306; Database=db; UID=dbuid; PWD=xx;Pooling=true;Max Pool Size=12;Min Pool Size=2;Connection Lifetime=60" /> </connectionStrings>

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  • Media query from a specific folder

    - by sensei
    I would like to understand how I can use a cursor to jpg files in a folder specified in the sdcard. I'm trying to select with a cursor the jpg files in a specific folder, and I tried this: This is the code: public static Uri getRandomImage(ContentResolver resolver) { String[] projection = new String[] { BaseColumns._ID, }; String folder = "/sdcard/DCIM/Wallpaper/"; folder = folder + "%"; Uri uri = Media.EXTERNAL_CONTENT_URI; String[] whereArgs = new String[]{folder}; Cursor cursor = resolver.query(uri, projection, null, whereArgs, MediaColumns._ID); if (cursor == null || cursor.getCount() <= 0) { return null; } cursor.moveToPosition(new Random().nextInt(cursor.getCount())); return Uri.withAppendedPath(uri, cursor.getString(0)); } but this code gives me error here is the logcat: E/AndroidRuntime(11986): FATAL EXCEPTION: main E/AndroidRuntime(11986): android.database.sqlite.SQLiteException: bind or column index out of range: handle 0x26a490 E/AndroidRuntime(11986): at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:158) E/AndroidRuntime(11986): at android.database.DatabaseUtils.readExceptionFromParcel(DatabaseUtils.java:114) E/AndroidRuntime(11986): at android.content.ContentProviderProxy.bulkQueryInternal(ContentProviderNative.java:330) E/AndroidRuntime(11986): at android.content.ContentProviderProxy.query(ContentProviderNative.java:366) E/AndroidRuntime(11986): at android.content.ContentResolver.query(ContentResolver.java:245) E/AndroidRuntime(11986): at it.bisemanuDEV.slidepuzzle.SelectImagePreference.getRandomImage(SelectImagePreference.java:126) E/AndroidRuntime(11986): at it.bisemanuDEV.slidepuzzle.TileView.newGame(TileView.java:156) E/AndroidRuntime(11986): at it.bisemanuDEV.slidepuzzle.SlidePuzzleActivity.onOptionsItemSelected(SlidePuzzleActivity.java:377) E/AndroidRuntime(11986): at android.app.Activity.onMenuItemSelected(Activity.java:2762) E/AndroidRuntime(11986): at com.android.internal.policy.impl.PhoneWindow.onMenuItemSelected(PhoneWindow.java:730) E/AndroidRuntime(11986): at com.android.internal.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:143) E/AndroidRuntime(11986): at com.android.internal.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:855) E/AndroidRuntime(11986): at com.android.internal.view.menu.IconMenuView.invokeItem(IconMenuView.java:532) E/AndroidRuntime(11986): at com.android.internal.view.menu.IconMenuItemView.performClick(IconMenuItemView.java:122) E/AndroidRuntime(11986): at android.view.View$PerformClick.run(View.java:8819) E/AndroidRuntime(11986): at android.os.Handler.handleCallback(Handler.java:603) E/AndroidRuntime(11986): at android.os.Handler.dispatchMessage(Handler.java:92) E/AndroidRuntime(11986): at android.os.Looper.loop(Looper.java:123) E/AndroidRuntime(11986): at android.app.ActivityThread.main(ActivityThread.java:4627) E/AndroidRuntime(11986): at java.lang.reflect.Method.invokeNative(Native Method) E/AndroidRuntime(11986): at java.lang.reflect.Method.invoke(Method.java:521) E/AndroidRuntime(11986): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868) E/AndroidRuntime(11986): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626) E/AndroidRuntime(11986): at dalvik.system.NativeStart.main(Native Method)

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  • What is the best way to update an unattached entity on Entity Framework?

    - by Carlos Loth
    Hi, In my project I have some data classes to retrieve data from the database using the Entity Framework. We called these classes *EntityName*Manager. All of them have a method to retrieve entities from database and they behave most like this: static public EntityA SelectByName(String name) { using (var context = new ApplicationContext()) { var query = from a in context.EntityASet where a.Name == name select a; try { var entityA = query.First(); context.Detach(entityA); return entityA; } catch (InvalidOperationException ex) { throw new DataLayerException( String.Format("The entityA whose name is '{0}' was not found.", name), ex); } } } You can see that I detach the entity before return it to the method caller. So, my question is "what is the best way to create an update method on my *EntityA*Manager class?" I'd like to pass the modified entity as a parameter of the method. But I haven't figured out a way of doing it without going to the database and reload the entity and update its values inside a new context. Any ideas? Thanks in advance, Carlos Loth.

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  • Python: Seeing all files in Hex.

    - by Recursion
    I am writing a python script which looks at common computer files and examines them for similar bytes, words, double word's. Though I need/want to see the files in Hex, ande cannot really seem to get python to open a simple file in python. I have tried codecs.open with hex as the encoding, but when I operate on the file descriptor it always spits back File "main.py", line 41, in <module> main() File "main.py", line 38, in main process_file(sys.argv[1]) File "main.py", line 27, in process_file seeker(line.rstrip("\n")) File "main.py", line 15, in seeker for unit in f.read(2): File "/usr/lib/python2.6/codecs.py", line 666, in read return self.reader.read(size) File "/usr/lib/python2.6/codecs.py", line 472, in read newchars, decodedbytes = self.decode(data, self.errors) File "/usr/lib/python2.6/encodings/hex_codec.py", line 50, in decode return hex_decode(input,errors) File "/usr/lib/python2.6/encodings/hex_codec.py", line 42, in hex_decode output = binascii.a2b_hex(input) TypeError: Non-hexadecimal digit found def seeker(_file): f = codecs.open(_file, "rb", "hex") for LINE in f.read(): print LINE f.close() I really just want to see files, and operate on them as if it was in a hex editor like xxd. Also is it possible to read a file in increments of maybe a word at a time. No this is not homework.

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  • Wrappers/law of demeter seems to be an anti-pattern...

    - by Robert Fraser
    I've been reading up on this "Law of Demeter" thing, and it (and pure "wrapper" classes in general) seem to generally be anti patterns. Consider an implementation class: class Foo { void doSomething() { /* whatever */ } } Now consider two different implementations of another class: class Bar1 { private static Foo _foo = new Foo(); public static Foo getFoo() { return _foo; } } class Bar2 { private static Foo _foo = new Foo(); public static void doSomething() { _foo.doSomething(); } } And the ways to call said methods: callingMethod() { Bar1.getFoo().doSomething(); // Version 1 Bar2.doSomething(); // Version 2 } At first blush, version 1 seems a bit simpler, and follows the "rule of Demeter", hide Foo's implementation, etc, etc. But this ties any changes in Foo to Bar. For example, if a parameter is added to doSomething, then we have: class Foo { void doSomething(int x) { /* whatever */ } } class Bar1 { private static Foo _foo = new Foo(); public static Foo getFoo() { return _foo; } } class Bar2 { private static Foo _foo = new Foo(); public static void doSomething(int x) { _foo.doSomething(x); } } callingMethod() { Bar1.getFoo().doSomething(5); // Version 1 Bar2.doSomething(5); // Version 2 } In both versions, Foo and callingMethod need to be changed, but in Version 2, Bar also needs to be changed. Can someone explain the advantage of having a wrapper/facade (with the exception of adapters or wrapping an external API or exposing an internal one).

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  • Using the groupby method in Python, example included

    - by randombits
    Trying to work with groupby so that I can group together files that were created on the same day. When I say same day in this case, I mean the dd part in mm/dd/yyyy. So if a file was created on March 1 and April 1, they should be grouped together because the "1" matches. Here's the code I have so far: #!/usr/bin/python import os import datetime from itertools import groupby def created_ymd(fn): ts = os.stat(fn).st_ctime dt = datetime.date.fromtimestamp(ts) return dt.year, dt.month, dt.day def get_files(): files = [] for f in os.listdir(os.getcwd()): if not os.path.isfile(f): continue y,m,d = created_ymd(f) files.append((f, d)) return files files = get_files() for key, group in groupby(files, lambda x: x[1]): for file in group: print "file: %s, date: %s" % (file[0], key) print " " The problem is, I get lots of files that get grouped together based on the day. But then I'll see multiple groups with the same day. Meaning I might have 4 files grouped that were created on the 17th. Later on I'll see another unique set of 2 files that are also created on the 17th. Where am I going wrong?

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  • Can I write this regex in one step?

    - by Marin Doric
    This is the input string "23x +y-34 x + y+21x - 3y2-3x-y+2". I want to surround every '+' and '-' character with whitespaces but only if they are not allready sourrounded from left or right side. So my input string would look like this "23x + y - 34 x + y + 21x - 3y2 - 3x - y + 2". I wrote this code that does the job: Regex reg1 = new Regex(@"\+(?! )|\-(?! )"); input = reg1.Replace(input, delegate(Match m) { return m.Value + " "; }); Regex reg2 = new Regex(@"(?<! )\+|(?<! )\-"); input = reg2.Replace(input, delegate(Match m) { return " " + m.Value; }); explanation: reg1 // Match '+' followed by any character not ' ' (whitespace) or same thing for '-' reg2 // Same thing only that I match '+' or '-' not preceding by ' '(whitespace) delegate 1 and 2 just insert " " before and after m.Value ( match value ) Question is, is there a way to create just one regex and just one delegate? i.e. do this job in one step? I am a new to regex and I want to learn efficient way.

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  • Java: volatile guarantees and out-of-order execution

    - by WizardOfOdds
    Note that this question is solely about the volatile keyword and the volatile guarantees: it is not about the synchronized keyword (so please don't answer "you must use synchronize" for I don't have any issue to solve: I simply want to understand the volatile guarantees (or lack of guarantees) regarding out-of-order execution). Say we have an object containing two volatile String references that are initialized to null by the constructor and that we have only one way to modify the two String: by calling setBoth(...) and that we can only set their references afterwards to non-null reference (only the constructor is allowed to set them to null). For example (it's just an example, there's no question yet): public class SO { private volatile String a; private volatile String b; public SO() { a = null; b = null; } public void setBoth( @NotNull final String one, @NotNull final String two ) { a = one; b = two; } public String getA() { return a; } public String getB() { return b; } } In setBoth(...), the line assigning the non-null parameter "a" appears before the line assigning the non-null parameter "b". Then if I do this (once again, there's no question, the question is coming next): if ( so.getB() != null ) { System.out.println( so.getA().length ); } Am I correct in my understanding that due to out-of-order execution I can get a NullPointerException? In other words: there's no guarantee that because I read a non-null "b" I'll read a non-null "a"? Because due to out-of-order (multi)processor and the way volatile works "b" could be assigned before "a"? volatile guarantees that reads subsequent to a write shall always see the last written value, but here there's an out-of-order "issue" right? (once again, the "issue" is made on purpose to try to understand the semantics of the volatile keyword and the Java Memory Model, not to solve a problem).

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  • How to get the path of a derived class from an inherited method?

    - by Jacco
    How to get the path of the current class, from an inherited method? I have the following: <?php // file: /parentDir/class.php class Parent { protected function getDir() { return dirname(__FILE__); } } ?> and <?php // file: /childDir/class.php class Child extends Parent { public function __construct() { echo $this->getDir(); } } $tmp = new Child(); // output: '/parentDir' ?> The __FILE__ constant always points to the source-file of the file it is in, regardless of inheritance. I would like to get the name of the path for the derived class. Is there any elegant way of doing this? I could do something along the lines of $this->getDir(__FILE__); but that would mean that I have to repeat myself quite often. I'm looking for a method that puts all the logic in the parent class, if possible. Update: Accepted solution (by Palantir): <?php // file: /parentDir/class.php class Parent { protected function getDir() { $reflector = new ReflectionClass(get_class($this)); return dirname($reflector->getFileName()); } } ?>

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  • Editing a labels text value through JavaScript in VB ASP.NET

    - by Ronnie
    I have a simple form containing two text boxes, I am attempting to apply some validation to the first text box using JavaScript. This is the first time I have attempted this and am having some trouble. I have a label beside the text box stating an error, this labels visibility property is set to False. I wish the labels visibility to turn true if the text box is empty when the user loses focus. For this I have used the onBlur option within the tags of the text box. It then calls the JavaScript function and should set the label to Visible but it does not. I have tested to see if it is entering the function by using an alert instead and that works. The problem seems to be trying to alter the visibility property of the label. Here is the portion of my code: The JavaScript: function myRegEx(frm) { if ( boxUsername.value == "" ) { invalidUser.visible = True; return false; } } The form: <asp:TextBox onblur="return myRegEx(this)" id="boxUsername" runat="server" Width="200px"></asp:TextBox> <asp:Label id="invalidUser" runat="server" visible="False" forecolor="Red" text="* Username must be alphanumeric with no special characters"></asp:Label> Any help would be brilliant.

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  • Doctrine2 ArrayCollection

    - by boosis
    Ok, I have a User entity as follows <?php class User { /** * @var integer * @Id * @Column(type="integer") * @GeneratedValue */ protected $id; /** * @var \Application\Entity\Url[] * @OneToMany(targetEntity="Url", mappedBy="user", cascade={"persist", "remove"}) */ protected $urls; public function __construct() { $this->urls = new \Doctrine\Common\Collections\ArrayCollection(); } public function addUrl($url) { // This is where I have a problem } } Now, what I want to do is check if the User has already the $url in the $urls ArrayCollection before persisting the $url. Now some of the examples I found says we should do something like if (!$this->getUrls()->contains($url)) { // add url } but this doesn't work as this compares the element values. As the $url doesn't have id value yet, this will always fail and $url will be dublicated. So I'd really appreciate if someone could explain how I can add an element to the ArrayCollection without persisting it and avoiding the duplication? Edit I have managed to achive this via $p = function ($key, $element) use ($url) { if ($element->getUrlHash() == $url->getUrlHash()) { return true; } else { return false; } }; But doesn't this still load all urls and then performs the check? I don't think this is efficient as there might be thousands of urls per user.

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  • Reference-type conversion operators: asking for trouble?

    - by Ben
    When I compile the following code using g++ class A {}; void foo(A&) {} int main() { foo(A()); return 0; } I get the following error messages: > g++ test.cpp -o test test.cpp: In function ‘int main()’: test.cpp:10: error: invalid initialization of non-const reference of type ‘A&’ from a temporary of type ‘A’ test.cpp:6: error: in passing argument 1 of ‘void foo(A&)’ After some reflection, these errors make plenty of sense to me. A() is just a temporary value, not an assignable location on the stack, so it wouldn't seem to have an address. If it doesn't have an address, then I can't hold a reference to it. Okay, fine. But wait! If I add the following conversion operator to the class A class A { public: operator A&() { return *this; } }; then all is well! My question is whether this even remotely safe. What exactly does this point to when A() is constructed as a temporary value? I am given some confidence by the fact that void foo(const A&) {} can accept temporary values according to g++ and all other compilers I've used. The const keyword can always be cast away, so it would surprise me if there were any actual semantic differences between a const A& parameter and an A& parameter. So I guess that's another way of asking my question: why is a const reference to a temporary value considered safe by the compiler whereas a non-const reference is not?

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  • ObjC: Alloc instance of Class and performing selectors on it leads to __CFRequireConcreteImplementat

    - by Arakyd
    Hi, I'm new to Objective-C and I'd like to abstract my database access using a model class like this: @interface LectureModel : NSMutableDictionary { } -(NSString*)title; -(NSDate*)begin; ... @end I use the dictionary methods setValue:forKey: to store attributes and return these in the getters. Now I want to read these models from a sqlite database by using the Class dynamically. + (NSArray*)findBySQL:(NSString*)sql intoModelClass:(Class)modelClass { NSMutableArray* models = [[[NSMutableArray alloc] init] autorelease]; sqlite3* db = sqlite3_open(...); sqlite3_stmt* result = NULL; sqlite3_prepare_v2(db, [sql UTF8String], -1, &result, NULL); while(sqlite3_step(result) == SQLITE_ROW) { id modelInstance = [[modelClass alloc] init]; for (int i = 0; i < sqlite3_column_count(result); ++i) { NSString* key = [NSString stringWithUTF8String:sqlite3_column_name(result, i)]; NSString* value = [NSString stringWithUTF8String:(const char*)sqlite3_column_text(result, i)]; if([modelInstance respondsToSelector:@selector(setValue:forKey:)]) [modelInstance setValue:value forKey:key]; } [models addObject:modelInstance]; } sqlite3_finalize(result); sqlite3_close(db); return models; } Funny thing is, the respondsToSelector: works, but if I try (in the debugger) to step over [modelInstance setValue:value forKey:key], it will throw an exception, and the stacktrace looks like: #0 0x302ac924 in ___TERMINATING_DUE_TO_UNCAUGHT_EXCEPTION___ #1 0x991d9509 in objc_exception_throw #2 0x302d6e4d in __CFRequireConcreteImplementation #3 0x00024d92 in +[DBManager findBySQL:intoModelClass:] at DBManager.m:114 #4 0x0001ea86 in -[FavoritesViewController initializeTableData:] at FavoritesViewController.m:423 #5 0x0001ee41 in -[FavoritesViewController initializeTableData] at FavoritesViewController.m:540 #6 0x305359da in __NSFireDelayedPerform #7 0x302454a0 in CFRunLoopRunSpecific #8 0x30244628 in CFRunLoopRunInMode #9 0x32044c31 in GSEventRunModal #10 0x32044cf6 in GSEventRun #11 0x309021ee in UIApplicationMain #12 0x00002988 in main at main.m:14 So, what's wrong with this? Presumably I'm doing something really stupid and just don't see it... Many thanks in advance for your answers, Arakyd :..

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  • VBA Public Function to Excel

    - by Sugih
    Dear sir , I have create below function Option Explicit Public Function fyi(x As Double, f As String) As String Application.Volatile Dim data As Double Dim post(5) post(1) = "Ribu " post(2) = "Juta " post(3) = "Milyar " post(4) = "Trilyun " post(5) = "Ribu Trilyun " Dim part As String Dim text As String Dim cond As Boolean Dim i As Integer If (x < 0) Then fyi = " " Exit Function End If If (x = 0) Then fyi = "Nol" Exit Function End If If (x < 2000) Then cond = True End If text = " " If (x >= 1E+15) Then fyi = "Nilai Terlalu Besar" Exit Function End If For i = 4 To 1 Step -1 data = Int(x / (10 ^ (3 * i))) If (data 0) Then part = fyis(data, cond) text = text & part & post(i) End If x = x - data * (10 ^ (3 * i)) Next text = text & fyis(x, False) fyi = text & f End Function Function fyis(ByVal y As Double, ByVal conds As Boolean) As String Dim datas As Double Dim posts(2) posts(1) = "Puluh" posts(2) = "Ratus" Dim parts As String Dim texts As String 'Dim conds As Boolean Dim j As Integer Dim value(9) value(1) = "Se" value(2) = "Dua " value(3) = "Tiga " value(4) = "Empat " value(5) = "Lima " value(6) = "Enam " value(7) = "Tujuh " value(8) = "Delapan " value(9) = "Sembilan " texts = " " For j = 2 To 1 Step -1 datas = Int(y / 10 ^ j) If (datas 0) Then parts = value(datas) If (j = 1 And datas = 1) Then y = y - datas * 10 ^ j If (y = 1) Then posts(j) = "belas" Else value(y) = "Se" End If texts = texts & value(y) & posts(j) fyis = texts Exit Function Else texts = texts & parts & posts(j) End If End If y = y - datas * 10 ^ j Next If (conds = False) Then value(1) = "Satu " End If texts = texts & value(y) fyis = texts End Function but when I return to Excel and type '=fyi(500,"USD") it return to #name? please do me favor to inform me how to solve Rgds, Sugih

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  • iphone encryption not working

    - by Futur
    I have this encryption/decryption implemented and executes with no error, but i am unable to decrypt the data and im not sure whether the data is encrypted, kindly help. - (NSData *)AES256EncryptWithKey:(NSString *)key { char keyPtr[kCCKeySizeAES256+1]; bzero(keyPtr, sizeof(keyPtr)); [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; NSUInteger dataLength = [strData length]; data = [[NSData alloc] init]; data = [strData dataUsingEncoding:NSUTF8StringEncoding]; size_t bufferSize = dataLength + kCCBlockSizeAES128; void *pribuffer = malloc(bufferSize); size_t numBytesEncrypted = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, keyPtr, kCCKeySizeAES256, NULL /* initialization vector (optional) */, [data bytes], dataLength, /* input */ [data bytes], bufferSize, /* output */ &numBytesEncrypted); if (cryptStatus == kCCSuccess) { return [NSData dataWithBytesNoCopy:data length:numBytesEncrypted]; }} The decryption is : -(NSData *)AES256DecryptWithKey:(NSString *)key andForData:(NSData *)objDataObject { char keyPtr[kCCKeySizeAES256+1]; bzero(keyPtr, sizeof(keyPtr)); [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; NSUInteger dataLength = [objDataObject length]; size_t bufferSize = dataLength + kCCBlockSizeAES128; void *buffer = malloc(bufferSize); size_t numBytesDecrypted = 0; CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, keyPtr, kCCKeySizeAES256, NULL, [objDataObject bytes], dataLength, [objDataObject bytes], bufferSize, &numBytesDecrypted); if (cryptStatus == kCCSuccess) { return [NSData dataWithBytesNoCopy:objDataObject length:numBytesDecrypted]; } } i call the above methods like this: CryptoClass *obj = [CryptoClass new]; NSData *objData = [obj AES256EncryptWithKey:@"hell"]; NSData *val = [obj AES256DecryptWithKey:@"hell" andForData:objData ]; NSLog(@"decrypted string is : %@ AND LENGTH IS %d",[val description],[val length]); Decryption doesnt seem to happen at all and the encryption - i am not sure about it, kindly help me here.

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  • Linq to sql DataContext cannot set load options after results been returned

    - by David Liddle
    I have two tables A and B with a one-to-many relationship respectively. On some pages I would like to get a list of A objects only. On other pages I would like to load A with objects in B attached. This can be handled by setting the load options DataLoadOptions options = new DataLoadOptions(); options.LoadWith<A>(a => a.B); dataContext.LoadOptions = options; The trouble occurs when I first of all view all A's with load options, then go to edit a single A (do not use load options), and after edit return to the previous page. I understand why the error is occurring but not sure how to best get round this problem. I would like the DataContext to be loaded up per request. I thought I was achieving this by using StructureMap to load up my DataContext on a per request basis. This is all part of an n-tier application where my Controllers call Services which in turn call Repositories. ForRequestedType<MyDataContext>() .CacheBy(InstanceScope.PerRequest) .TheDefault.Is.Object(new MyDataContext()); ForRequestedType<IAService>() .TheDefault.Is.OfConcreteType<AService>(); ForRequestedType<IARepository>() .TheDefault.Is.OfConcreteType<ARepository>(); Here is a brief outline of my Repository public class ARepository : IARepository { private MyDataContext db; public ARepository(MyDataContext context) { db = context; } public void SetLoadOptions(DataLoadOptions options) { db.LoadOptions = options; } public IQueryable<A> Get() { return from a in db.A select a; } So my ServiceLayer, on View All, sets the load options and then gets all A's. On editing A my ServiceLayer should spin up a new DataContext and just fetch a list of A's. When sql profiling, I can see that when I go to the Edit page it is requesting A with B objects.

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