Search Results

Search found 11901 results on 477 pages for 'triple store'.

Page 442/477 | < Previous Page | 438 439 440 441 442 443 444 445 446 447 448 449  | Next Page >

  • Inserting contact with android and querying the result uri returns no entries

    - by th0m4d
    Im developing an application which is dealing with the android contacts API. I implemented methods to insert, update and query contacts. So far everything worked (writing and reading contacts). At one point in my project Im experiencing a strange behaviour. I insert a contact using batch mode. I receive the URI to the RawContact. I do this in a background thread. // use batchmode for contact insertion ArrayList ops = new ArrayList(); int rawContactInsertIndex = ops.size(); // create rawContact ops.add(ContentProviderOperation.newInsert(RawContacts.CONTENT_URI) .withValue(RawContacts.ACCOUNT_TYPE, ConstantsContract.ACCOUNT_TYPE) .withValue(RawContacts.ACCOUNT_NAME, accountName).build()); ops.add(createInsertOperation().withValueBackReference(Data.RAW_CONTACT_ID, rawContactInsertIndex) .withValue(Data.MIMETYPE, StructuredName.CONTENT_ITEM_TYPE) .withValue(StructuredName.DISPLAY_NAME, displayName).withValue(StructuredName.GIVEN_NAME, firstName) .withValue(StructuredName.FAMILY_NAME, lastName).build()); //other data values... ContentProviderResult[] results = context.getContentResolver().applyBatch(ContactsContract.AUTHORITY, ops); if (results.length 0) { result = results[0]; } Then i request and store the lookup uri RawContacts.getContactLookupUri(this.getContentResolver(), myContantRawContactUri); I am able to query the contact using the rawContactUri directly after inserting it (in the same thread). The lookup uri returns null. Uri rawContactUri = appUser.getRawContactUri(ctx); if (rawContactUri == null) { return null; } String lastPathSegment = rawContactUri.getLastPathSegment(); long rawContactId = Long.decode(lastPathSegment); if (rawContactUri != null) { contact = readContactWithID(rawContactId, ContactsContract.Data.RAW_CONTACT_ID); In a different place in the project I want to query the contact i inserted by the stored lookup uri or raw contact uri. Both return no rows from the content provider. I tried it in the main thread and in another background thread. ctx.getContentResolver().query(ContactsContract.Data.CONTENT_URI, null, ContactsContract.Data.RAW_CONTACT_ID + " = ? AND " + ContactsContract.Data.MIMETYPE + " = ?", new String[] { contactID + "", ContactsContract.CommonDataKinds.StructuredName.CONTENT_ITEM_TYPE }, null); My first thought was that it could be related to the context.getContentResolver(). But the android documentation states, that the ContentResolver objects scope is the application's package, so you have on ContentResolver for the whole app. Am I right? What am I doing wrong? Why does the same rawContactUri return the contact at one place and does not on another place? And why do I get a lookup uri from a raw contact, which is not working at all?

    Read the article

  • Abstract Data Type: Any1 can help me this? thanks..

    - by Aga Hibaya
    Objectives: Implement the Abstract Data Type (ADT) List using dynamically allocated arrays and structures. Description A LIST is an ordered collection of items where items may be inserted anywhere in the list. Implement a LIST using an array as follows: struct list { int *items; // pointer to the array int size; // actual size of the array int count; // number of items in the array }; typedef struct list *List; // pointer to the structure Implement the following functions: a) List newList(int size); - will create a new List and return its pointer. Allocate space for the structure, allocate space for the array, then initialize size and count, return the pointer. b) void isEmpty(List list); c) void display(List list); d) int contains(List list, int item); e) void remove(List list, int i) ; f) void insertAfter(List list,int item, int i); g) void addEnd(List list,int item) - add item at the end of the list – simply store the data at position count, then increment count. If the array is full, allocate an array twice as big as the original. count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 addEnd(list,40) will result to count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 40 h) void addFront(List list,int item) - shift all elements to the right so that the item can be placed at position 0, then increment count. Bonus: if the array is full, allocate an array twice as big as the original. count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 addFront(list,40) will result to count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 i) void removeFront(List list) - shift all elements to the left and decrement count; count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 removeFront(list) will result to count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 5 10 15 20 30 j) void remove(List list,int item) - get the index of the item in the list and then shift all elements to the count = 6 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 10 15 20 30 remove(list,10) will result to count = 5 size = 10 0 1 2 3 4 5 6 7 8 9 40 5 15 20 30 Remarks

    Read the article

  • NSLinguisticTagger on the contents of an NSTextStorage- crashing bug

    - by Remy Porter
    I'm trying to use an NSLinguisticTagger to monitor the contents of an NSTextStorage and provide some contextual information based on what the user types. To that end, I have an OverlayManager object, which wires up this relationship: -(void) setView:(NSTextView*) view { _view = view; _layout = view.layoutManager; _storage = view.layoutManager.textStorage; //get the TextStorage from the view [_tagger setString:_storage.string]; //pull the string out, this grabs the mutable version [self registerForNotificationsOn:self->_storage]; //subscribe to the willProcessEditing notification } When an edit occurs, I make sure to trap it and notify the tagger (and yes, I know I'm being annoyingly inconsistent with member access, I'm rusty on Obj-C, I'll fix it later): - (void) textStorageWillProcessEditing:(NSNotification*) notification{ if ([self->_storage editedMask] & NSTextStorageEditedCharacters) { NSRange editedRange = [self->_storage editedRange]; NSUInteger delta = [self->_storage changeInLength]; [_tagger stringEditedInRange:editedRange changeInLength:delta]; //should notify the tagger of the changes [self highlightEdits:self]; } } The highlightEdits message delegates the job out to a pool of "Overlay" objects. Each contains a block of code similar to this: [tagger enumerateTagsInRange:range scheme:NSLinguisticTagSchemeLexicalClass options:0 usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop) { if (tag == PartOfSpeech) { [self applyHighlightToRange:tokenRange onStorage:storage]; } }]; And that's where the problem is- the enumerateTagsInRange method crashes out with a message: 2014-06-04 10:07:19.692 WritersEditor[40191:303] NSMutableRLEArray replaceObjectsInRange:withObject:length:: Out of bounds This problem doesn't occur if I don't link to the mutable copy of the underlying string and instead do a [[_storage string] copy], but obviously I don't want to copy the entire backing store every time I want to do tagging. This all should be happening in the main run loop, so I don't think this is a threading issue. The NSRange I'm enumerating tags on exists both in the NSTextStorage and in the NSLinguisticTagger's view of the string. It's not even the fact that the applyHighlightToRange call adds attributes to the string, because it crashes before even reaching that line. I attempted to build a test case around the problem, but can't replicate it in those situations: - (void) testEdit { NSAttributedString* str = [[NSMutableAttributedString alloc] initWithString:@"Quickly, this is a test."]; text = [[NSTextStorage alloc] initWithAttributedString:str]; NSArray* schemes = [NSLinguisticTagger availableTagSchemesForLanguage:@"en"]; tagger = [[NSLinguisticTagger alloc] initWithTagSchemes:schemes options:0]; [tagger setString:[text string]]; [text beginEditing]; [[text mutableString] appendString:@"T"]; NSRange edited = [text editedRange]; NSUInteger length = [text changeInLength]; [text endEditing]; [tagger stringEditedInRange:edited changeInLength:length]; [tagger enumerateTagsInRange:edited scheme:NSLinguisticTagSchemeLexicalClass options:0 usingBlock:^(NSString *tag, NSRange tokenRange, NSRange sentenceRange, BOOL *stop) { //doesn't matter, this should crash }]; } That code doesn't crash.

    Read the article

  • SQLAlchemy unsupported type error - and table design issues?

    - by Az
    Hi there, back again with some more SQLAlchemy shenanigans. Let me step through this. My table is now set up as so: engine = create_engine('sqlite:///:memory:', echo=False) metadata = MetaData() students_table = Table('studs', metadata, Column('sid', Integer, primary_key=True), Column('name', String), Column('preferences', Integer), Column('allocated_rank', Integer), Column('allocated_project', Integer) ) metadata.create_all(engine) mapper(Student, students_table) Fairly simple, and for the most part I've been enjoying the ability to query almost any bit of information I want provided I avoid the error cases below. The class it is mapped from is: class Student(object): def __init__(self, sid, name): self.sid = sid self.name = name self.preferences = collections.defaultdict(set) self.allocated_project = None self.allocated_rank = 0 def __repr__(self): return str(self) def __str__(self): return "%s %s" %(self.sid, self.name) Explanation: preferences is basically a set of all the projects the student would prefer to be assigned. When the allocation algorithm kicks in, a student's allocated_project emerges from this preference set. Now if I try to do this: for student in students.itervalues(): session.add(student) session.commit() It throws two errors, one for the allocated_project column (seen below) and a similar error for the preferences column: sqlalchemy.exc.InterfaceError: (InterfaceError) Error binding parameter 4 - probably unsupported type. u'INSERT INTO studs (sid, name, allocated_rank, allocated_project) VALUES (?, ?, ?, ?, ?, ?, ?)' [1101, 'Muffett,M.', 1, 888 Human-spider relationships (Supervisor id: 123)] If I go back into my code I find that, when I'm copying the preferences from the given text files, it actually refers to the Project class which is mapped to a dictionary, using the unique project id's (pid) as keys. Thus, as I iterate through each student via their rank and to the preferences set, it adds not a project id, but the reference to the project id from the projects dictionary. students[sid].preferences[int(rank)].add(projects[int(pid)]) Now this is very useful to me since I can find out all I want to about a student's preferred projects without having to run another check to pull up information about the project id. The form you see in the error has the object print information passed as: return "%s %s (Supervisor id: %s)" %(self.proj_id, self.proj_name, self.proj_sup) My questions are: I'm trying to store an object in a database field aren't I? Would the correct way then, be copying the project information (project id, name, etc) into its own table, referenced by the unique project id? That way I can just have the project id field for one of the student tables just be an integer id and when I need more information, just join the tables? So and so forth for other tables? If the above makes sense, then how does one maintain the relationship with a column of information in one table which is a key index on another table? Does this boil down into a database design problem? Are there any other elegant ways of accomplishing this? Apologies if this is a very long-winded question. It's rather crucial for me to solve this, so I've tried to explain as much as I can, whilst attempting to show that I'm trying (key word here sadly) to understand what could be going wrong.

    Read the article

  • How to get compatibility between C# and SQL2k8 AES Encryption?

    - by Victor Rodrigues
    I have an AES encryption being made on two columns: one of these columns is stored at a SQL Server 2000 database; the other is stored at a SQL Server 2008 database. As the first column's database (2000) doesn't have native functionality for encryption / decryption, we've decided to do the cryptography logic at application level, with .NET classes, for both. But as the second column's database (2008) allow this kind of functionality, we'd like to make the data migration using the database functions to be faster, since the data migration in SQL 2k is much smaller than this second and it will last more than 50 hours because of being made at application level. My problem started at this point: using the same key, I didn't achieve the same result when encrypting a value, neither the same result size. Below we have the full logic in both sides.. Of course I'm not showing the key, but everything else is the same: private byte[] RijndaelEncrypt(byte[] clearData, byte[] Key) { var memoryStream = new MemoryStream(); Rijndael algorithm = Rijndael.Create(); algorithm.Key = Key; algorithm.IV = InitializationVector; var criptoStream = new CryptoStream(memoryStream, algorithm.CreateEncryptor(), CryptoStreamMode.Write); criptoStream.Write(clearData, 0, clearData.Length); criptoStream.Close(); byte[] encryptedData = memoryStream.ToArray(); return encryptedData; } private byte[] RijndaelDecrypt(byte[] cipherData, byte[] Key) { var memoryStream = new MemoryStream(); Rijndael algorithm = Rijndael.Create(); algorithm.Key = Key; algorithm.IV = InitializationVector; var criptoStream = new CryptoStream(memoryStream, algorithm.CreateDecryptor(), CryptoStreamMode.Write); criptoStream.Write(cipherData, 0, cipherData.Length); criptoStream.Close(); byte[] decryptedData = memoryStream.ToArray(); return decryptedData; } This is the SQL Code sample: open symmetric key columnKey decryption by password = N'{pwd!!i_ll_not_show_it_here}' declare @enc varchar(max) set @enc = dbo.VarBinarytoBase64(EncryptByKey(Key_GUID('columnKey'), 'blablabla')) select LEN(@enc), @enc This varbinaryToBase64 is a tested sql function we use to convert varbinary to the same format we use to store strings in the .net application. The result in C# is: eg0wgTeR3noWYgvdmpzTKijkdtTsdvnvKzh+uhyN3Lo= The same result in SQL2k8 is: AI0zI7D77EmqgTQrdgMBHAEAAACyACXb+P3HvctA0yBduAuwPS4Ah3AB4Dbdj2KBGC1Dk4b8GEbtXs5fINzvusp8FRBknF15Br2xI1CqP0Qb/M4w I just didn't get yet what I'm doing wrong. Do you have any ideas? EDIT: One point I think is crucial: I have one Initialization Vector at my C# code, 16 bytes. This IV is not set at SQL symmetric key, could I do this? But even not filling the IV in C#, I get very different results, both in content and length.

    Read the article

  • programming question

    - by shivam
    using System; using System.Data; using System.Collections.Generic; using System.ComponentModel; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using System.Data.SqlClient; namespace datasynchronization { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { string connectString = @"Data Source=MOON\SQL2005;Initial Catalog=databaseA;Integrated Security=True"; using (var srcCon = new SqlConnection(connectString)) //connection to source table { srcCon.Open();//source table connection open SqlCommand cmd = new SqlCommand();// sqlobject for source table cmd.Connection = srcCon; string connectionString = @"Data Source=MOON\SQL2005;Initial Catalog=databaseB;Integrated Security=True"; using (var tgtCon = new SqlConnection(connectionString)) //connection to target table { tgtCon.Open(); //target table connection open SqlCommand objcmd1 = new SqlCommand();//sqlobject for target table objcmd1.Connection = tgtCon; objcmd1.CommandText = "SELECT MAX(date) FROM Table_2"; //query to findout the max date from target table var maxdate = objcmd1.ExecuteScalar(); // store the value of max date into the variable maxdate cmd.CommandText = string.Format("SELECT id,date,name,city,salary,region FROM Table_1 where date >'{0}'", maxdate); //select query to fetch rows from source table using (var reader = cmd.ExecuteReader()) { SqlCommand objcmd = new SqlCommand(); objcmd.Connection = tgtCon; objcmd.CommandText = "INSERT INTO Table_2(id,date,name,city,salary,region)VALUES(@id,@date,@name,@city,@salary,@region)"; objcmd.Parameters.Add("@id", SqlDbType.Int); objcmd.Parameters.Add("@date", SqlDbType.DateTime); objcmd.Parameters.Add("@name", SqlDbType.NVarChar); objcmd.Parameters.Add("@city", SqlDbType.NVarChar); objcmd.Parameters.Add("@salary", SqlDbType.Int); objcmd.Parameters.Add("@region", SqlDbType.Char); while (reader.Read()) { var order1 = reader[0].ToString(); var order2 = reader[1].ToString(); var order3 = reader[2].ToString(); var order4 = reader[3].ToString(); var order5 = reader[4].ToString(); var order6 = reader[5].ToString(); objcmd.Parameters["@id"].Value = order1; objcmd.Parameters["@date"].Value = order2; objcmd.Parameters["@name"].Value = order3; objcmd.Parameters["@city"].Value = order4; objcmd.Parameters["@salary"].Value = order5; objcmd.Parameters["@region"].Value = order6; objcmd.ExecuteNonQuery(); } } tgtCon.Close(); } srcCon.Close(); } } } } how can i organize the above written code in an efficient way?

    Read the article

  • Entity Framework looking for wrong column

    - by m.edmondson
    I'm brand new to the Entity Framework and trying to learn all it can offer. I'm currently working my way through the MVC Music Store tutorial which includes the following code: public ActionResult Browse(string genre) { // Retrieve Genre and its Associated Albums from database var genreModel = storeDB.Genres.Include("Albums") .Single(g => g.Name == genre); return View(genreModel); } as I'm working in VB I converted it like so: Function Browse(ByVal genre As String) As ActionResult 'Retrieve Genre and its Associated Albums from database Dim genreModel = storeDB.Genres.Include("Albums"). _ Single(Function(g) g.Name = genre) Return(View(genreModel)) End Function The problem is I'm getting the following exception: Invalid column name 'GenreGenreId'. Which I know is true, but I can't for the life of my work out where it's getting 'GenreGenreId' from. Probably a basic question but I'll appreciate any help in the right direction. As per requested here is the source for my classes: Album.vb Public Class Album Private _title As String Private _genre As Genre Private _AlbumId As Int32 Private _GenreId As Int32 Private _ArtistId As Int32 Private _Price As Decimal Private _AlbumArtUrl As String Public Property Title As String Get Return _title End Get Set(ByVal value As String) _title = value End Set End Property Public Property AlbumId As Int16 Get Return _AlbumId End Get Set(ByVal value As Int16) _AlbumId = value End Set End Property Public Property GenreId As Int16 Get Return _GenreId End Get Set(ByVal value As Int16) _GenreId = value End Set End Property Public Property ArtistId As Int16 Get Return _ArtistId End Get Set(ByVal value As Int16) _ArtistId = value End Set End Property Public Property AlbumArtUrl As String Get Return _AlbumArtUrl End Get Set(ByVal value As String) _AlbumArtUrl = value End Set End Property Public Property Price As Decimal Get Return _Price End Get Set(ByVal value As Decimal) _Price = value End Set End Property Public Property Genre As Genre Get Return _genre End Get Set(ByVal value As Genre) _genre = value End Set End Property End Class Genre.vb Public Class Genre Dim _genreId As Int32 Dim _Name As String Dim _Description As String Dim _Albums As List(Of Album) Public Property GenreId As Int32 Get Return _genreId End Get Set(ByVal value As Int32) _genreId = value End Set End Property Public Property Name As String Get Return _Name End Get Set(ByVal value As String) _Name = value End Set End Property Public Property Description As String Get Return _Description End Get Set(ByVal value As String) _Description = value End Set End Property Public Property Albums As List(Of Album) Get Return _Albums End Get Set(ByVal value As List(Of Album)) _Albums = value End Set End Property End Class MusicStoreEntities.vb Imports System.Data.Entity Namespace MvcApplication1 Public Class MusicStoreEntities Inherits DbContext Public Property Albums As DbSet(Of Album) Public Property Genres As DbSet(Of Genre) End Class End Namespace

    Read the article

  • Creating thumbnails PHP problem

    - by Wayne
    I have this source code where I got it from net tutsplus. I have configured it and made it work in one PHP file. It does work by transferring the original image, but it does not generate to the thumbnails folder. <?php $final_width_of_image = 100; $path_to_image_directory = "../../img/events/" . urldecode($_GET['name']) . "/"; $path_to_thumbs_directory = "../../img/events/" . urldecode($_GET['name']) . "/thumbnails/"; function createThumbnail($filename) { if(preg_match('/[.](jpg)$/', $filename)) { $im = imagecreatefromjpeg($path_to_image_directory . $filename); } elseif(preg_match('/[.](gif)$/', $filename)) { $im = imagecreatefromgif($path_to_image_directory . $filename); } elseif(preg_match('/[.](png)$/', $filename)) { $im = imagecreatefrompng($path_to_image_directory . $filename); } $ox = imagesx($im); $oy = imagesy($im); $nx = $final_width_of_image; $ny = floor($oy * ($final_width_of_image / $ox)); $nm = imagecreatetruecolor($nx, $ny); imagecopyresized($nm, $im, 0,0,0,0,$nx,$ny,$ox,$oy); imagejpeg($nm, $path_to_thumbs_directory . $filename); $tn = '<img src="' . $path_to_thumbs_directory . $filename . '" alt="image" />'; echo $tn; } if(isset($_FILES['fupload'])) { if(preg_match('/[.](jpg)|(gif)|(png)$/', $_FILES['fupload']['name'])) { $filename = $_FILES['fupload']['name']; $source = $_FILES['fupload']['tmp_name']; $target = $path_to_image_directory . $filename; move_uploaded_file($source, $target); createThumbnail($filename); } } ?> Basically it is supposed to generate a thumbnail of the uploaded image and store the original image into a different folder. The paths are correct, it works by getting the folder name in the URL, it does work, but nothing works for the thumbnails folder. BEFORE you ask this related question, yes, thumbnails generation does work on my server by the PHP GD, I have tested it separately. So this is not the problem. :) How do I get this to work? :(

    Read the article

  • iPhone RSS thumbnail

    I have a simple RSS reader. Stories are downloaded, put into a UITableView, and when you click it, each story loads in a UIWebView. It works great. Now though, I'd like to incorporate an image on the left side (like you'd see in the YouTube app). However, since my app pulls from an RSS feed, I can't simply specify image X to appear in row X because row X will be row Y tomorrow, and things will get out of order, you know? I am currently pulling from a YouTube RSS feed, and can get the video title, description, publication date, but I'm stuck as to how to pull the little thumbnail besides each entry in the feed. As you can probably tell, I'm a coding newbie (this being my first application other than a Hello World app) and I'm getting so frustrated by my own lack of knowledge. Thanks! BTW, here's some sample code: - (void)parser:(NSXMLParser *)parser didStartElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName attributes:(NSDictionary *)attributeDict{ //NSLog(@"found this element: %@", elementName); if (currentElement) { [currentElement release]; currentElement = nil; } currentElement = [elementName copy]; if ([elementName isEqualToString:@"item"]) { // clear out our story item caches... item = [[NSMutableDictionary alloc] init]; currentTitle = [[NSMutableString alloc] init]; currentDate = [[NSMutableString alloc] init]; currentSummary = [[NSMutableString alloc] init]; currentLink = [[NSMutableString alloc] init]; } } - (void)parser:(NSXMLParser *)parser didEndElement:(NSString *)elementName namespaceURI:(NSString *)namespaceURI qualifiedName:(NSString *)qName{ //NSLog(@"ended element: %@", elementName); if ([elementName isEqualToString:@"item"]) { // save values to an item, then store that item into the array... [item setObject:currentTitle forKey:@"title"]; [item setObject:currentLink forKey:@"link"]; [item setObject:currentSummary forKey:@"summary"]; [item setObject:currentDate forKey:@"date"]; [stories addObject:[item copy]]; NSLog(@"adding story: %@", currentTitle); } } - (void)parser:(NSXMLParser *)parser foundCharacters:(NSString *)string{ //NSLog(@"found characters: %@", string); // save the characters for the current item... if ([currentElement isEqualToString:@"title"]) { [currentTitle appendString:string]; } else if ([currentElement isEqualToString:@"link"]) { [currentLink appendString:string]; } else if ([currentElement isEqualToString:@"description"]) { [currentSummary appendString:string]; } else if ([currentElement isEqualToString:@"pubDate"]) { [currentDate appendString:string]; } }

    Read the article

  • Web image loaded by thread in android

    - by Bostjan
    I have an extended BaseAdapter in a ListActivity: private static class RequestAdapter extends BaseAdapter { and some handlers and runnables defined in it // Need handler for callbacks to the UI thread final Handler mHandler = new Handler(); // Create runnable for posting final Runnable mUpdateResults = new Runnable() { public void run() { loadAvatar(); } }; protected static void loadAvatar() { // TODO Auto-generated method stub //ava.setImageBitmap(getImageBitmap("URL"+pic)); buddyIcon.setImageBitmap(avatar); } In the getView function of the Adapter, I'm getting the view like this: if (convertView == null) { convertView = mInflater.inflate(R.layout.messageitem, null); // Creates a ViewHolder and store references to the two children views // we want to bind data to. holder = new ViewHolder(); holder.username = (TextView) convertView.findViewById(R.id.username); holder.date = (TextView) convertView.findViewById(R.id.dateValue); holder.time = (TextView) convertView.findViewById(R.id.timeValue); holder.notType = (TextView) convertView.findViewById(R.id.notType); holder.newMsg = (ImageView) convertView.findViewById(R.id.newMsg); holder.realUsername = (TextView) convertView.findViewById(R.id.realUsername); holder.replied = (ImageView) convertView.findViewById(R.id.replied); holder.msgID = (TextView) convertView.findViewById(R.id.msgID_fr); holder.avatar = (ImageView) convertView.findViewById(R.id.buddyIcon); holder.msgPreview = (TextView) convertView.findViewById(R.id.msgPreview); convertView.setTag(holder); } else { // Get the ViewHolder back to get fast access to the TextView // and the ImageView. holder = (ViewHolder) convertView.getTag(); } and the image is getting loaded this way: Thread sepThread = new Thread() { public void run() { String ava; ava = request[8].replace(".", "_micro."); Log.e("ava thread",ava+", username: "+request[0]); avatar = getImageBitmap(URL+ava); buddyIcon = holder.avatar; mHandler.post(mUpdateResults); //holder.avatar.setImageBitmap(getImageBitmap(URL+ava)); } }; sepThread.start(); Now, the problem I'm having is that if there are more items that need to display the same picture, not all of those pictures get displayed. When you scroll up and down the list maybe you end up filling all of them. When I tried the commented out line (holder.avatar.setImageBitmap...) the app sometimes force closes with "only the thread that created the view can request...". But only sometimes. Any idea how I can fix this? Either option.

    Read the article

  • Compose synthetic English phrase that would contain 160 bits of recoverable information

    - by Alexander Gladysh
    I have 160 bits of random data. Just for fun, I want to generate pseudo-English phrase to "store" this information in. I want to be able to recover this information from the phrase. Note: This is not a security question, I don't care if someone else will be able to recover the information or even detect that it is there or not. Criteria for better phrases, from most important to the least: Short Unique Natural-looking The current approach, suggested here: Take three lists of 1024 nouns, verbs and adjectives each (picking most popular ones). Generate a phrase by the following pattern, reading 20 bits for each word: Noun verb adjective verb, Noun verb adjective verb, Noun verb adjective verb, Noun verb adjective verb. Now, this seems to be a good approach, but the phrase is a bit too long and a bit too dull. I have found a corpus of words here (Part of Speech Database). After some ad-hoc filtering, I calculated that this corpus contains, approximately 50690 usable adjectives 123585 nouns 15301 verbs This allows me to use up to 16 bits per adjective (actually 16.9, but I can't figure how to use fractional bits) 15 bits per noun 13 bits per verb For noun-verb-adjective-verb pattern this gives 57 bits per "sentence" in phrase. This means that, if I'll use all words I can get from this corpus, I can generate three sentences instead of four (160 / 57 ˜ 2.8). Noun verb adjective verb, Noun verb adjective verb, Noun verb adjective verb. Still a bit too long and dull. Any hints how can I improve it? What I see that I can try: Try to compress my data somehow before encoding. But since the data is completely random, only some phrases would be shorter (and, I guess, not by much). Improve phrase pattern, so it would look better. Use several patterns, using the first word in phrase to somehow indicate for future decoding which pattern was used. (For example, use the last letter or even the length of the word.) Pick pattern according to the first bytes of the data. ...I'm not that good with English to come up with better phrase patterns. Any suggestions? Use more linguistics in the pattern. Different tenses etc. ...I guess, I would need much better word corpus than I have now for that. Any hints where can I get a suitable one?

    Read the article

  • XCode sqlite3 - SELECT always return SQLITE_DONE

    - by user573633
    Hi developers.... a noob here asking for help after a day of head-banging.... I am working on an app with sqlite3 database with one database and two tables. I have now come to a step where I want to select from the table with an argument. The code is here: -(NSMutableArray*) getGroupsPeopleWhoseGroupName:(NSString*)gn;{ NSMutableArray *groupedPeopleArray = [[NSMutableArray alloc] init]; const char *sql = "SELECT * FROM Contacts WHERE groupName='?'"; @try { NSArray * paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES); NSString *docsDir = [paths objectAtIndex:0]; NSString *theDBPath = [docsDir stringByAppendingPathComponent:@"ContactBook.sqlite"]; if (!(sqlite3_open([theDBPath UTF8String], &database) == SQLITE_OK)) { NSLog(@"An error opening database."); } sqlite3_stmt *st; NSLog(@"debug004 - sqlite3_stmt success."); if (sqlite3_prepare_v2(database, sql, -1, &st, NULL) != SQLITE_OK) { NSLog(@"Error, failed to prepare statement."); } //DB is ready for accessing, now start getting all the info. while (sqlite3_step(st) == SQLITE_ROW) { MyContacts * aContact = [[MyContacts alloc] init]; //get contactID from DB. aContact.contactID = sqlite3_column_int(st, 0); if (sqlite3_column_text(st, 1) != NULL) { aContact.firstName = [NSString stringWithUTF8String:(char *) sqlite3_column_text(st, 1)]; } else { aContact.firstName = @""; } // here retrieve other columns data .... //store these info retrieved into the newly created array. [groupedPeopleArray addObject:aContact]; [aContact release]; } if(sqlite3_finalize(st) != SQLITE_OK) { NSLog(@"Failed to finalize data statement."); } if (sqlite3_close(database) != SQLITE_OK) { NSLog(@"Failed to close database."); } } @catch (NSException *e) { NSLog(@"An exception occurred: %@", [e reason]); return nil; } return groupedPeopleArray;} MyContacts is the class where I put up all the record variables. My problem is sqlite3_step(st) always return SQLITE_DONE, so that it i can never get myContacts. (i verified this by checking the return value). What am I doing wrong here? Many thanks in advance!

    Read the article

  • Inline HTML Syntax for Helpers in ASP.NET MVC

    - by kouPhax
    I have a class that extends the HtmlHelper in MVC and allows me to use the builder pattern to construct special output e.g. <%= Html.FieldBuilder<MyModel>(builder => { builder.Field(model => model.PropertyOne); builder.Field(model => model.PropertyTwo); builder.Field(model => model.PropertyThree); }) %> Which outputs some application specific HTML, lets just say, <ul> <li>PropertyOne: 12</li> <li>PropertyTwo: Test</li> <li>PropertyThree: true</li> </ul> What I would like to do, however, is add a new builder methid for defining some inline HTML without having to store is as a string. E.g. I'd like to do this. <% Html.FieldBuilder<MyModel>(builder => { builder.Field(model => model.PropertyOne); builder.Field(model => model.PropertyTwo); builder.ActionField(model => %> Generated: <%=DateTime.Now.ToShortDate()%> (<a href="#">Refresh</a>) <%); }).Render(); %> and generate this <ul> <li>PropertyOne: 12</li> <li>PropertyTwo: Test</li> <li>Generated: 29/12/2008 <a href="#">Refresh</a></li> </ul> Essentially an ActionExpression that accepts a block of HTML. However to do this it seems I need to execute the expression but point the execution of the block to my own StringWriter and I am not sure how to do this. Can anyone advise?

    Read the article

  • SDL Video Init causes Exception on Mac OS X 10.8

    - by ScrollerBlaster
    I have just ported my C++ game to OS X and the first time it ran I get the following exception when trying to call SDL_SetVideoMode. 2012-09-28 15:01:05.437 SCRAsteroids[28595:707] * Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'Error (1000) creating CGSWindow on line 259' * First throw call stack: ( 0 CoreFoundation 0x00007fff8b53b716 __exceptionPreprocess + 198 1 libobjc.A.dylib 0x00007fff90e30470 objc_exception_throw + 43 2 CoreFoundation 0x00007fff8b53b4ec +[NSException raise:format:] + 204 3 AppKit 0x00007fff8a26a579 _NSCreateWindowWithOpaqueShape2 + 655 4 AppKit 0x00007fff8a268d70 -[NSWindow _commonAwake] + 2002 5 AppKit 0x00007fff8a2277e2 -[NSWindow _commonInitFrame:styleMask:backing:defer:] + 1763 6 AppKit 0x00007fff8a22692f -[NSWindow _initContent:styleMask:backing:defer:contentView:] + 1568 7 AppKit 0x00007fff8a2262ff -[NSWindow initWithContentRect:styleMask:backing:defer:] + 45 8 libSDL-1.2.0.dylib 0x0000000107c228f6 -[SDL_QuartzWindow initWithContentRect:styleMask:backing:defer:] + 294 9 libSDL-1.2.0.dylib 0x0000000107c20505 QZ_SetVideoMode + 2837 10 libSDL-1.2.0.dylib 0x0000000107c17af5 SDL_SetVideoMode + 917 11 SCRAsteroids 0x0000000107be60fb _ZN11SDLGraphics4initEP6IWorldii + 291 ) libc++abi.dylib: terminate called throwing an exception Abort trap: 6 My init code looks like this: if (SDL_Init(SDL_INIT_EVERYTHING) < 0) return false; const SDL_VideoInfo *videoInfo = SDL_GetVideoInfo(); if (!videoInfo) { fprintf(stderr, "Video query failed: %s\n", SDL_GetError()); return false; } /* the flags to pass to SDL_SetVideoMode */ videoFlags = SDL_OPENGL; /* Enable OpenGL in SDL */ videoFlags |= SDL_GL_DOUBLEBUFFER; /* Enable double buffering */ videoFlags |= SDL_HWPALETTE; /* Store the palette in hardware */ /* This checks to see if surfaces can be stored in memory */ if (videoInfo->hw_available) videoFlags |= SDL_HWSURFACE; else videoFlags |= SDL_SWSURFACE; if (w == 0) { widthViewport = videoInfo->current_w; heightViewport = videoInfo->current_h; cout << "Will use full screen resolution of "; videoFlags |= SDL_FULLSCREEN; } else { cout << "Will use full user supplied resolution of "; widthViewport = w; heightViewport = h; videoFlags |= SDL_RESIZABLE; /* Enable window resizing */ } cout << widthViewport << "x" << heightViewport << "\n"; /* This checks if hardware blits can be done */ if (videoInfo->blit_hw) videoFlags |= SDL_HWACCEL; /* Sets up OpenGL double buffering */ SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); /* get a SDL surface */ surface = SDL_SetVideoMode(widthViewport, heightViewport, SCREEN_BPP, videoFlags); It gets into that last SDL call and throws the exception above. I have tried it in both full screen and resizable window mode, same thing. I build my app old school, on the command line, as opposed to using Xcode.

    Read the article

  • Should an event-sourced aggregate root have access to the event sourcing repository?

    - by JD Courtoy
    I'm working on an event-sourced CQRS implementation, using DDD in the application / domain layer. I have an object model that looks like this: public class Person : AggregateRootBase { private Guid? _bookingId; public Person(Identification identification) { Apply(new PersonCreatedEvent(identification)); } public Booking CreateBooking() { // Enforce Person invariants var booking = new Booking(); Apply(new PersonBookedEvent(booking.Id)); return booking; } public void Release() { // Enforce Person invariants // Should we load the booking here from the aggregate repository? // We need to ensure that booking is released as well. var booking = BookingRepository.Load(_bookingId); booking.Release(); Apply(new PersonReleasedEvent(_bookingId)); } [EventHandler] public void Handle(PersonBookedEvent @event) { _bookingId = @event.BookingId; } [EventHandler] public void Handle(PersonReleasedEvent @event) { _bookingId = null; } } public class Booking : AggregateRootBase { private DateTime _bookingDate; private DateTime? _releaseDate; public Booking() { //Enforce invariants Apply(new BookingCreatedEvent()); } public void Release() { //Enforce invariants Apply(new BookingReleasedEvent()); } [EventHandler] public void Handle(BookingCreatedEvent @event) { _bookingDate = SystemTime.Now(); } [EventHandler] public void Handle(BookingReleasedEvent @event) { _releaseDate = SystemTime.Now(); } // Some other business activities unrelated to a person } With my understanding of DDD so far, both Person and Booking are seperate aggregate roots for two reasons: There are times when business components will pull Booking objects separately from the database. (ie, a person that has been released has a previous booking modified due to incorrect information). There should not be locking contention between Person and Booking whenever a Booking needs to be updated. One other business requirement is that a Booking can never occur for a Person more than once at a time. Due to this, I'm concerned about querying the query database on the read side as there could potentially be some inconsistency there (due to using CQRS and having an eventually consistent read database). Should the aggregate roots be allowed to query the event-sourced backing store by id for objects (lazy-loading them as needed)? Are there any other avenues of implementation that would make more sense?

    Read the article

  • Invalid cast exception

    - by user127147
    I have a simple application to store address details and edit them. I have been away from VB for a few years now and need to refreash my knowledge while working to a tight deadline. I have a general Sub responsible for displaying a form where user can add contact details (by pressing button add) and edit them (by pressing button edit). This sub is stored in a class Contact. The way it is supposed to work is that there is a list with all the contacts and when new contact is added a new entry is displayed. If user wants to edit given entry he or she selects it and presses edit button Public Sub Display() Dim C As New Contact C.Cont = InputBox("Enter a title for this contact.") C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text frmStart.lstContact.Items.Add(C.Cont.ToString) End Sub I call it from the form responsible for adding new contacts by Dim C As New Contact C.Display() and it works just fine. However when I try to do something similar using the edit button I get errors - "Unable to cast object of type 'System.String' to type 'AddressBook.Contact'." Dim C As Contact If lstContact.SelectedItem IsNot Nothing Then C = lstContact.SelectedItem() C.Display() End If I think it may be something simple however I wasn't able to fix it and given short time I have I decided to ask for help here. I have updated my class with advice from other members and here is the final version (there are some problems however). When I click on the edit button it displays only the input box for the title of the contact and actually adds another entry in the list with previous data for first name, second name etc. Public Class Contact Public Contact As String Public Fname As String Public Surname As String Public Address As String Private myCont As String Public Property Cont() Get Return myCont End Get Set(ByVal value) myCont = Value End Set End Property Public Overrides Function ToString() As String Return Me.Cont End Function Sub NewContact() FName = frmAddCont.txtFName.ToString frmStart.lstContact.Items.Add(FName) frmAddCont.Hide() End Sub Public Sub Display() Dim C As New Contact C.Cont = InputBox("Enter a title for this contact.") C.Fname = frmAddCont.txtFName.Text C.Surname = frmAddCont.txtSName.Text C.Address = frmAddCont.txtAddress.Text 'frmStart.lstContact.Items.Add(C.Cont.ToString) frmStart.lstContact.Items.Add(C) End Sub End Class

    Read the article

  • Error Handling for Application in PHP

    - by Zubair1
    I was wondering if someone can show me a good way to handle errors in my PHP app, that i am also easily able to reuse in my codes. So far i have been using the following functions: Inline Errors function display_errors_for($fieldname) { global $errors; if (isset($errors[$fieldname])) { return '<label for="' .$fieldname. '" class="error">' . ucfirst($errors[$fieldname]). '</label>'; } else { return false; } } All Errrors function display_all_errors($showCounter = true) { global $errors; $counter = 0; foreach ($errors as $errorFieldName => $errorText) { if ($showCounter == true) { $counter++; echo '<li>' . $counter . ' - <label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } else { echo '<li><label for="' .$errorFieldName. '">' .$errorText. '</label></li>'; } } } I have a $errors = array(); defined on the top of my global file, so it is appended to all files. The way i use it is that if i encounter an error, i push a new error key/value to the $errors array holder, something like the following: if (strlen($username) < 3) { $errors['username'] = "usernames cannot be less then 3 characters."; } This all works great and all, But i wondering if some one has a better approach for this? with classes? i don't think i want to use Exceptions with try/catch seems like an overkill to me. I'm planning to make a new app, and i'll be getting my hands wet with OOP alot, though i have already made apps using OOP but this time i'm planning to go even deeper and use OOP approach more extensively. What i have in mind is something like this, though its just a basic class i will add further detail to it as i go deeper and deeper in my app to see what it needs. class Errors { public $errors = array(); public function __construct() { // Initialize Default Values // Initialize Methods } public function __destruct() { //nothing here too... } public function add($errorField, $errorDesc) { if (!is_string($errorField)) return false; if (!is_string($errorDesc)) return false; $this->errors[$errorField] = $errorDesc; } public function display($errorsArray) { // code to iterate through the array and display all errors. } } Please share your thoughts, if this is a good way to make a reusable class to store and display errors for an entire app, or is getting more familiar with exceptions and try/catch my only choice?

    Read the article

  • Deterministic key serialization

    - by Mike Boers
    I'm writing a mapping class which uses SQLite as the storage backend. I am currently allowing only basestring keys but it would be nice if I could use a couple more types hopefully up to anything that is hashable (ie. same requirements as the builtin dict). To that end I would like to derive a deterministic serialization scheme. Ideally, I would like to know if any implementation/protocol combination of pickle is deterministic for hashable objects (e.g. can only use cPickle with protocol 0). I noticed that pickle and cPickle do not match: >>> import pickle >>> import cPickle >>> def dumps(x): ... print repr(pickle.dumps(x)) ... print repr(cPickle.dumps(x)) ... >>> dumps(1) 'I1\n.' 'I1\n.' >>> dumps('hello') "S'hello'\np0\n." "S'hello'\np1\n." >>> dumps((1, 2, 'hello')) "(I1\nI2\nS'hello'\np0\ntp1\n." "(I1\nI2\nS'hello'\np1\ntp2\n." Another option is to use repr to dump and ast.literal_eval to load. This would only be valid for builtin hashable types. I have written a function to determine if a given key would survive this process (it is rather conservative on the types it allows): def is_reprable_key(key): return type(key) in (int, str, unicode) or (type(key) == tuple and all( is_reprable_key(x) for x in key)) The question for this method is if repr itself is deterministic for the types that I have allowed here. I believe this would not survive the 2/3 version barrier due to the change in str/unicode literals. This also would not work for integers where 2**32 - 1 < x < 2**64 jumping between 32 and 64 bit platforms. Are there any other conditions (ie. do strings serialize differently under different conditions)? (If this all fails miserably then I can store the hash of the key along with the pickle of both the key and value, then iterate across rows that have a matching hash looking for one that unpickles to the expected key, but that really does complicate a few other things and I would rather not do it.) Any insights?

    Read the article

  • Generating custom-form documents from base-form plus XML?

    - by KlaymenDK
    Hi all, this is my first stack overflow, and it's a complex one. Sorry. My task is to generate custom documents from a basic template plus some XML without having a custom form design element for each case. Here's the whole picture: We are building a Lotus Notes (client, not web) application for world-wide application access control; the scope is something like 400.000 users being able to request access to any of 1000+ applications. Each application needs its own request form -- different number of approvers, various info required, that sort of thing. We simply can't have a thousand forms in a database (one per application), and anyway their maintenance really needs to be pushed from the developers to the application owners. So instead of custom forms, we'd like to create a generic "template" form that stores a block of basic fields, but then allows application owners to define another block of fields dynamically -- "I want a mandatory plain-text field named 'Name' here, and then a date field named 'Due' here that must be later than today's date, and then ...". I hope this makes sense (if not, think of it as a generic questionnaire application). I pretty much have the structure in place for designing the dynamic fields (form builder GUI - XML-encoded data - pre-rendered DXL for injecting into a form), including mark-up for field types, value options, and rudimentary field validation instructions. My problem is generating a document with this dynamic content injected at the proper location (without needing a custom form design element for each case). Doing the dynamic content via HTML is out. The Notes client web rendering is simply way too poor, and it would be quite a challenge to implement things like field validation instructions, date selectors, and name look-ups. DXL, on the other hand, would allow us to use native Notes fields and code. As a tech demo, I've managed to implement a custom form generator that injects the pre-rendered DXL for the dynamic content into a base form; but as I said, we don't want a ton of custom form design elements. I've tried to implement a way to create a document with the "store form in document" flag set, but once I've created the document from the base form, I can't get DXL access to the stored form design, and so I can't inject my dynamic content. I know this is not something Notes was ever intended to do. Has anyone ever tried something like it (and gotten away with it)? Thanks for reading this far. With a boatload of thanks in advance, Jan Gundtofte-Bruun

    Read the article

  • Problem while adding new Object to CoreData App

    - by elementsense
    Hi Another Day, another CoreData problem,...but hopefully the last one now. Ok here is a copy of what I have : I have a List of Hotel Guests that stay in one Room and have Preferences. Once ready the user should select a guest and see the data and should also be able to add new guest, select the room (maintained also by application) and select their preferences (where the user can also add new preferences). The guest can have no or many preferences. So here is what I have so far. I created 3 Entities : - Rooms with roomnumber - Preferences with name - GuestInfo with name - with these Relationships room (Destination Rooms) and prefs (Destination Preferences with "To-Many Relationship") The prefs is a NSSet when you create a Managed Object Class. Now I created a UITableViewController to display all the data. I also have an edit and add mode. When I add a new Guest and just fill out the name, everything works fine. But when I want to add the prefs or the room number I get this error : Illegal attempt to establish a relationship 'room' between objects in different contexts Now, what confuses me is that when I add a guest and enter just the name, save it, go back and edit it and select the prefs and room number it works ? I have this line in both ViewControllers to select the room or prefs : [editedObject setValue:selectedRoom forKey:editedFieldKey]; with this .h : NSManagedObject *editedObject; NSString *editedFieldKey; NSString *editedFieldName; Again, it works on the editing mode but not when I want to add a fresh object. And to be sure, this is what I do for adding an new Guest : - (IBAction)addNewItem { AddViewController *addViewController = [[AddViewController alloc] initWithStyle:UITableViewStyleGrouped]; addViewController.delegate = self; addViewController.context = _context; // Create a new managed object context for the new book -- set its persistent store coordinator to the same as that from the fetched results controller's context. NSManagedObjectContext *addingContext = [[NSManagedObjectContext alloc] init]; self.addingManagedObjectContext = addingContext; [addingContext release]; [addingManagedObjectContext setPersistentStoreCoordinator:[[_fetchedResultsController managedObjectContext] persistentStoreCoordinator]]; GuestInfo *info = (GuestInfo *)[NSEntityDescription insertNewObjectForEntityForName:@"GuestInfo" inManagedObjectContext:addingContext]; addViewController.info = info; UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:addViewController]; [self.navigationController presentModalViewController:navController animated:YES]; [addViewController release]; [navController release]; } Anything I have to do to initialize the Room or Prefs ? Hope someone can help me out. Thanks

    Read the article

  • How to keep a local value from being set when a binding fails (so inherited values will propagate)

    - by redoced
    Consider the following scenario: I want to bind the TextElement.FontWeight property to an xml attribute. The xml looks somewhat like this and has arbitrary depth. <text font-weight="bold"> bold text here <inlinetext>more bold text</inlinetext> even more bold text </text> I use hierarchical templating to display the text, no problem there, but having a Setter in the template style like: <Setter Property="TextElement.FontWeight" Value="{Binding XPath=@font-weight}"/> sets the fontweight correctly on the first level, but overwrites the second level with null (as the binding can't find the xpath) which reverts to Fontweight normal. I tried all sorts of things here but nothing quite seems to work. e.g. i used a converter to return UnsetValue, which didn't work. I'm currently trying with: <Setter Property="custom:AttributeInserter.Wrapper" Value="{custom:AttributeInserter Property=TextElement.FontWeight, Binding={Binding XPath=@font-weight}}"/> Codebehind: public static class AttributeInserter { public static AttributeInserterExtension GetWrapper(DependencyObject obj) { return (AttributeInserterExtension)obj.GetValue(WrapperProperty); } public static void SetWrapper(DependencyObject obj, AttributeInserterExtension value) { obj.SetValue(WrapperProperty, value); } // Using a DependencyProperty as the backing store for Wrapper. This enables animation, styling, binding, etc... public static readonly DependencyProperty WrapperProperty = DependencyProperty.RegisterAttached("Wrapper", typeof(AttributeInserterExtension), typeof(AttributeInserter), new UIPropertyMetadata(pcc)); static void pcc(DependencyObject o,DependencyPropertyChangedEventArgs e) { var n=e.NewValue as AttributeInserterExtension; var c = o as FrameworkElement; if (n == null || c==null || n.Property==null || n.Binding==null) return; var bex = c.SetBinding(n.Property, n.Binding); bex.UpdateTarget(); if (bex.Status == BindingStatus.UpdateTargetError) c.ClearValue(n.Property); } } public class AttributeInserterExtension : MarkupExtension { public override object ProvideValue(IServiceProvider serviceProvider) { return this; } public DependencyProperty Property { get; set; } public Binding Binding { get; set; } } which kinda works, but can't track changes of the property Any ideas? Any links? thx for the help

    Read the article

  • Clojure vars and Java static methods

    - by j-g-faustus
    I'm a few days into learning Clojure and are having some teething problems, so I'm asking for advice. I'm trying to store a Java class in a Clojure var and call its static methods, but it doesn't work. Example: user=> (. java.lang.reflect.Modifier isPrivate 1) false user=> (def jmod java.lang.reflect.Modifier) #'user/jmod user=> (. jmod isPrivate 1) java.lang.IllegalArgumentException: No matching method found: isPrivate for class java.lang.Class (NO_SOURCE_FILE:0) at clojure.lang.Compiler.eval(Compiler.java:4543) From the exception it looks like the runtime expects a var to hold an object, so it calls .getClass() to get the class and looks up the method using reflection. In this case the var already holds a class, so .getClass() returns java.lang.Class and the method lookup obviously fails. Is there some way around this, other than writing my own macro? In the general case I'd like to have either an object or a class in a varible and call the appropriate methods on it - duck typing for static methods as well as for instance methods. In this specific case I'd just like a shorter name for java.lang.reflect.Modifier, an alias if you wish. I know about import, but looking for something more general, like the Clojure namespace alias but for Java classes. Are there other mechanisms for doing this? Edit: Maybe I'm just confused about the calling conventions here. I thought the Lisp (and by extension Clojure) model was to evaluate all arguments and call the first element in the list as a function. In this case (= jmod java.lang.reflect.Modifier) returns true, and (.getName jmod) and (.getName java.lang.reflect.Modifier) both return the same string. So the variable and the class name clearly evaluate to the same thing, but they still cannot be called in the same fashion. What's going on here? Edit 2 Answering my second question (what is happening here), the Clojure doc says that If the first operand is a symbol that resolves to a class name, the access is considered to be to a static member of the named class... Otherwise it is presumed to be an instance member http://clojure.org/java_interop under "The Dot special form" "Resolving to a class name" is apparently not the same as "evaluating to something that resolves to a class name", so what I am trying to do here is something the dot special form does not support.

    Read the article

  • What are the weaknesses of this user authentication method?

    - by byronh
    I'm developing my own PHP framework. It seems all the security articles I have read use vastly different methods for user authentication than I do so I could use some help in finding security holes. Some information that might be useful before I start. I use mod_rewrite for my MVC url's. Passwords are sha1 and md5 encrypted with 24 character salt unique to each user. mysql_real_escape_string and/or variable typecasting on everything going in, and htmlspecialchars on everything coming out. Step-by step process: Top of every page: session_start(); session_regenerate_id(); If user logs in via login form, generate new random token to put in user's MySQL row. Hash is generated based on user's salt (from when they first registered) and the new token. Store the hash and plaintext username in session variables, and duplicate in cookies if 'Remember me' is checked. On every page, check for cookies. If cookies set, copy their values into session variables. Then compare $_SESSION['name'] and $_SESSION['hash'] against MySQL database. Destroy all cookies and session variables if they don't match so they have to log in again. If login is valid, some of the user's information from the MySQL database is stored in an array for easy access. So far, I've assumed that this array is clean so when limiting user access I refer to user.rank and deny access if it's below what's required for that page. I've tried to test all the common attacks like XSS and CSRF, but maybe I'm just not good enough at hacking my own site! My system seems way too simple for it to actually be secure (the security code is only 100 lines long). What am I missing? I've also spent alot of time searching for the vulnerabilities with mysql_real_escape string but I haven't found any information that is up-to-date (everything is from several years ago at least and has apparently been fixed). All I know is that the problem was something to do with encoding. If that problem still exists today, how can I avoid it? Any help will be much appreciated.

    Read the article

  • C# Select clause returns system exception instead of relevant object

    - by Kashif
    I am trying to use the select clause to pick out an object which matches a specified name field from a database query as follows: objectQuery = from obj in objectList where obj.Equals(objectName) select obj; In the results view of my query, I get: base {System.SystemException} = {"Boolean Equals(System.Object)"} Where I should be expecting something like a Car, Make, or Model Would someone please explain what I am doing wrong here? The method in question can be seen here: // this function searches the database's table for a single object that matches the 'Name' property with 'objectName' public static T Read<T>(string objectName) where T : IEquatable<T> { using (ISession session = NHibernateHelper.OpenSession()) { IQueryable<T> objectList = session.Query<T>(); // pull (query) all the objects from the table in the database int count = objectList.Count(); // return the number of objects in the table // alternative: int count = makeList.Count<T>(); IQueryable<T> objectQuery = null; // create a reference for our queryable list of objects T foundObject = default(T); // create an object reference for our found object if (count > 0) { // give me all objects that have a name that matches 'objectName' and store them in 'objectQuery' objectQuery = from obj in objectList where obj.Equals(objectName) select obj; // make sure that 'objectQuery' has only one object in it try { foundObject = (T)objectQuery.Single(); } catch { return default(T); } // output some information to the console (output screen) Console.WriteLine("Read Make: " + foundObject.ToString()); } // pass the reference of the found object on to whoever asked for it return foundObject; } } Note that I am using the interface "IQuatable<T>" in my method descriptor. An example of the classes I am trying to pull from the database is: public class Make: IEquatable<Make> { public virtual int Id { get; set; } public virtual string Name { get; set; } public virtual IList<Model> Models { get; set; } public Make() { // this public no-argument constructor is required for NHibernate } public Make(string makeName) { this.Name = makeName; } public override string ToString() { return Name; } // Implementation of IEquatable<T> interface public virtual bool Equals(Make make) { if (this.Id == make.Id) { return true; } else { return false; } } // Implementation of IEquatable<T> interface public virtual bool Equals(String name) { if (this.Name.Equals(name)) { return true; } else { return false; } } } And the interface is described simply as: public interface IEquatable<T> { bool Equals(T obj); }

    Read the article

  • WPF Reusing Xaml Effectively

    - by Steve
    Hi, I've recently been working on a project using WPF to produce a diagram. In this I must show text alongside symbols that illustrate information associated with the text. To draw the symbols I initially used some png images I had produced. Within my diagram these images appeared blurry and only looked worse when zoomed in on. To improve on this I decided I would use a vector rather than a rastor image format. Below is the method I used to get the rastor image from a file path: protected Image GetSymbolImage(string symbolPath, int symbolHeight) { Image symbol = new Image(); symbol.Height = symbolHeight; BitmapImage bitmapImage = new BitmapImage(); bitmapImage.BeginInit(); bitmapImage.UriSource = new Uri(symbolPath); bitmapImage.DecodePixelHeight = symbolHeight; bitmapImage.EndInit(); symbol.Source = bitmapImage; return symbol; } Unfortunately this does not recognise vector image formats. So instead I used a method like the following, where "path" is the file path to a vector image of the format .xaml: public static Canvas LoadXamlCanvas(string path) { //if a file exists at the specified path if (File.Exists(path)) { //store the text in the file string text = File.ReadAllText(path); //produce a canvas from the text StringReader stringReader = new StringReader(text); XmlReader xmlReader = XmlReader.Create(stringReader); Canvas c = (Canvas)XamlReader.Load(xmlReader); //return the canvas return c; } return null; } This worked but drastically killed performance when called repeatedly. I found the logic necessary for text to canvas conversion (see above) was the main cause of the performance problem therefore embedding the .xaml images would not alone resolve the performance issue. I tried using this method only on the initial load of my application and storing the resulting canvases in a dictionary that could later be accessed much quicker but I later realised when using the canvases within the dictionary I would have to make copies of them. All the logic I found online associated with making copies used a XamlWriter and XamlReader which would again just introduce a performance problem. The solution I used was to copy the contents of each .xaml image into its own user control and then make use of these user controls where appropriate. This means I now display vector graphics and performance is much better. However this solution to me seems pretty clumsy. I'm new to WPF and wonder if there is some built in way of storing and reusing xaml throughout an application? Apologies for the length of this question. I thought having a record of my attempts might help someone with any similar problem. Thanks.

    Read the article

< Previous Page | 438 439 440 441 442 443 444 445 446 447 448 449  | Next Page >