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  • How to call a method after asynchronous task is complete

    - by doctordoder
    I have a class called WikiWebView which is a subclass of UIWebView which loads Wikipedia subjects and is designed to fetch all the links of the webpage, in order to create a sort of site map for the subject. My problem is that I can only create the links once the web page has loaded, but the loading isn't done right after [self loadRequest:requestObj] is called. - (void)loadSubject:(NSString *)subject { // load the actual webpage NSString *wiki = @"http://www.wikipedia.org/wiki/"; NSString *fullURL = [wiki stringByAppendingString:subject]; NSURL *url = [NSURL URLWithString:fullURL]; NSURLRequest *requestObj = [NSURLRequest requestWithURL:url]; [self loadRequest:requestObj]; // [self createLinks]; // need this to be called after the view has loaded } - (void)createLinks { NSString *javascript = @"var string = \"\";" "var arr = document.getElementsByClassName(\"mw-redirect\");" "for (var i = 0; i < arr.length; ++i)" "{" "var redirectLink = arr[i].href;" "string = string + redirectLink + \" \";" "}" "string;"; NSString *links = [self stringByEvaluatingJavaScriptFromString:javascript]; self.links = [links componentsSeparatedByString:@" "]; } I tried the normal delegation technique, which lead to this code being added: - (id)init { if (self = [super init]) { self.delegate = self; // weird } return self; } #pragma mark - UIWebViewDelegate - (void)webViewDidStartLoad:(UIWebView *)webView { ++_numProcesses; } - (void)webView:(UIWebView *)webView didFailLoadWithError:(NSError *)error { --_numProcesses; } - (void)webViewDidFinishLoad:(UIWebView *)webView { --_numProcesses; if (_numProcesses == 0) { [self createLinks]; } } However, the delegate methods are never called.. I've seen similar questions where the answers are to use blocks, but how would I do that in this case?

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  • Responsive: two different toggles on same element

    - by Mathijs Delva
    I'm having difficulties with the following problem. For a responsive website, i need to use the same toggle element for both a toggle system for one window width, and another toggle system for a second window width. I have the following snippets: 1.A simple hover for a language dropdown, which should be executed for resolutions greater than 980px. $('#clickme').hover(function() { $(this).parent().find("#select-language").show(); $(this).find("> a span").css({"opacity":"0.5"}); }, function() { $(this).parent().find("#select-language").hide(); $(this).find("> a span").css({"opacity":"1"}); }); 2.A simple click for the same language toggle, which should be executed for resolutions smaller than 980px. jQuery('#clickme').click(function() { jQuery("#select-language-mobile").slideToggle("fast"); }); I need to nest these two, so that when the user is viewing the website in one resolution, the click function with be fired, and in the other case the hover function. Can anybody help me with this? PS: I'm sorry, but the code blocks don't seem to work at the moment.

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  • CSS to Make 2 Column Content Areas

    - by Joe Majewski
    I'm trying to stray away from using tables to form the layout of my content, and I can think of two alternatives that I'd like to better learn: (1) styling list items to be side-by-side, and (2) using div blocks that float onto the same line. Both of these would have their own uses for what I'm working on. I'm already using div tags to form the entire layout of my three-column template, but what I need to do now is a bit different. In case it helps, my project can be found here. In short, here's my question; how would I style a div so that the width of it is 50% of the width of the area it occupies, rather than 50% of the width of the page? As for my other question, what would be the best approach to styling list items so that they are side-by-side? I'm working on a registration script now, and instead of using a table with "Username" on the left and the input text on the right, I can use two list items. It's late and I've been working on this project of mine for about 8 hours straight now, so I apologize if I'm asking anything confusing. Feel free to ask me any questions about what I'm trying to do. Thanks, friends. :)

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  • (C++) Loading a file into a vector

    - by Alden
    This is probably a simple question, however I am new to C++ and I cannot figure this out. I am trying to load a binary file and load each byte to a vector. This works fine with a small file, but when I try to read larger than 410 bytes the program crashes and says: This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. I am using code::blocks on windows. This is the code: #include <iostream> #include <fstream> #include <vector> using namespace std; int main() { std::vector<char> vec; std::ifstream file; file.exceptions( std::ifstream::badbit | std::ifstream::failbit | std::ifstream::eofbit); file.open("file.bin"); file.seekg(0, std::ios::end); std::streampos length(file.tellg()); if (length) { file.seekg(0, std::ios::beg); vec.resize(static_cast<std::size_t>(length)); file.read(&vec.front(), static_cast<std::size_t>(length)); } int firstChar = static_cast<unsigned char>(vec[0]); cout << firstChar <<endl; return 0; } Thank you for your help!

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  • Image resizing efficiency in C# and .NET 3.5

    - by Matthew Nichols
    I have written a web service to resize user uploaded images and all works correctly from a functional point of view, but it causes CPU usage to spike every time it is used. It is running on Windows Server 2008 64 bit. I have tried compiling to 32 and 64 bit and get about the same results. The heart of the service is this function: private Image CreateReducedImage(Image imgOrig, Size NewSize) { var newBM = new Bitmap(NewSize.Width, NewSize.Height); using (var newGrapics = Graphics.FromImage(newBM)) { newGrapics.CompositingQuality = CompositingQuality.HighSpeed; newGrapics.SmoothingMode = SmoothingMode.HighSpeed; newGrapics.InterpolationMode = InterpolationMode.HighQualityBicubic; newGrapics.DrawImage(imgOrig, new Rectangle(0, 0, NewSize.Width, NewSize.Height)); } return newBM; } I put a profiler on the service and it seemed to indicate the vast majority of the time is spent in the GDI+ library itself and there is not much to be gained in my code. Questions: Am I doing something glaringly inefficient in my code here? It seems to conform to the example I have seen. Are there gains to be had in using libraries other than GDI+? The benchmarks I have seen seem to indicate that GDI+ does well compare to other libraries but I didn't find enough of these to be confident. Are there gains to be had by using "unsafe code" blocks? Please let me know if I have not included enough of the code...I am happy to put as much up as requested but don't want to be obnoxious in the post.

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  • Howto display or view encrypted data in encrypted form?

    - by Brian Gianforcaro
    In the Wikipedia Article on Block Cipher Modes they have a neat little diagram of an unencrypted image, the same image encrypted using ECB mode and another version of the same image encrypted using another method. At university I have developed my own implementation of DES (you can find it here) and we must demo our implementation in a presentation. I would like to display a similar example as shown above using our implementation. However most image files have header blocks associated with them, which when encrypting the file with our implementation, also get encrypted. So when you go to open them in an image viewer, they are assumed to be corrupted and can't be viewed. I was wondering if anybody new of a simple header-less image format which we could use to display these? Or if anyone had any idea's as to how the original creator of the images above achieved the above result? Any help would be appreciated, Thanks Note: I realise rolling your own cryptography library is stupid, and DES is considered broken, and ECB mode is very flawed for any useful cryptography, this was purely an academic exercise for school. So please, no lectures, I know the drill.

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  • Vectors or Java arrays for Tetris?

    - by StackedCrooked
    I'm trying to create a Tetris-like game with Clojure and I'm having some trouble deciding the data structure for the playing field. I want to define the playing field as a mutable grid. The individual blocks are also grids, but don't need to be mutable. My first attempt was to define a grid as a vector of vectors. For example an S-block looks like this: :s-block { :grids [ [ [ 0 1 1 ] [ 1 1 0 ] ] [ [ 1 0 ] [ 1 1 ] [ 0 1 ] ] ] } But that turns out to be rather tricky for simple things like iterating and painting (see the code below). For making the grid mutable my initial idea was to make each row a reference. But then I couldn't really figure out how to change the value of a specific cell in a row. One option would have been to create each individual cell a ref instead of each row. But that feels like an unclean approach. I'm considering using Java arrays now. Clojure's aget and aset functions will probably turn out to be much simpler. However before digging myself in a deeper mess I want to ask ideas/insights. How would you recommend implementing a mutable 2d grid? Feel free to share alternative approaches as well. Source code current state: Tetris.clj (rev452)

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  • Drawing animation

    - by HHHH
    I'm creating a simple app where when the user presses a button, a series of lines will be drawn on the screen and the user will be able to see these lines drawn in real time (almost like an animation). My code looks something like this (has been simplified): UIGraphicsBeginImageContext(CGSizeMake(300,300)); CGContextRef context = UIGraphicsGetCurrentContext(); for (int i = 0; i < 100; i++ ) { CGContextMoveToPoint(context, i, i); CGContextAddLineToPoint(context, i+20, i+20); CGContextSetStrokeColorWithColor(context, [[UIColor blackColor] CGColor]); CGContextStrokePath(context); } UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); My problem is that: 1) As soon as the user presses the button, the UIThread blocks until the drawing is done. 2) I can't get the lines to be drawn on the screen one at a time - I've tried setting the UIImage directly inside the loop and also tried setting a layer content inside the loop. How do I get around these problems?

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  • OSX: Programmatically added subviews not responding to mouse down events

    - by BigCola
    I have 3 subclasses: a Block class, a Row class and a Table class. All are subclasses of NSView. I have a Table added with IB which programmatically displays 8 rows, each of which displays 8 blocks. I overrode the mouseDown: method in Block to change the background color to red, but it doesn't work. Still if I add a block directly on top of the Table with IB it does work so I can't understand why it won't work in the first case. Here's the implementation code for Block and Row (Table's implementation works the same way as Row's): //block.m - (void)drawRect:(NSRect)dirtyRect { [color set]; [NSBezierPath fillRect:dirtyRect]; } -(void)mouseDown:(NSEvent *)theEvent { color = [NSColor redColor]; checked = YES; [self setNeedsDisplay:YES]; } //row.m - (void)drawRect:(NSRect)dirtyRect { [[NSColor blueColor] set]; [NSBezierPath fillRect:dirtyRect]; int x; for(x=0; x<8; x++){ int margin = x*2; NSRect rect = NSMakeRect(0, 50*x+margin, 50, 50); Block *block = [[Block alloc] initWithFrame:rect]; [self addSubview:block]; } }

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  • Java Socket Closes After Connection?

    - by Matthew
    Why does this port/socket close once a connection has been made by a client? package app; import java.io.*; import java.net.*; public class socketServer { public static void main(String[] args) { int port = 3333; boolean socketBindedToPort = false; try { ServerSocket ServerSocketPort = new ServerSocket(port); System.out.println("SocketServer Set Up on Port: " + port); socketBindedToPort = true; if(socketBindedToPort == true) { Socket clientSocket = null; try { clientSocket = ServerSocketPort.accept();//This method blocks until a socket connection has been made to this port. System.out.println("Waiting for client connection on port:" + port); /** THE CLIENT HAS MADE A CONNECTION **/ System.out.println("CLIENT IS CONENCTED"); } catch (IOException e) { System.out.println("Accept failed: " + port); System.exit(-1); } } else { System.out.println("Socket did not bind to the port:" + port); } } catch(IOException e) { System.out.println("Could not listen on port: " + port); System.exit(-1); } } }

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  • Guidelines for creating a programming-language enjoyable to write programs in?

    - by sub
    I'm currently working on the topic of programming-languages and interpreter-design. I have already created several programming languages but couldn't reach my goal so far: Create a programming-language which focuses on giving the programmer a good feeling when writing code in it. It should just be fun and/or interesting and in no case annoying to write something in it. I get this feeling when writing code in Python. I sometimes get the opposite with PHP and in rare cases when having to reinvent some wheel in C++. So I've tried to figure out some syntactical features to make programming in my new language fun, but I just can't find any. Which concrete features, maybe mainly in terms of syntax, do/could make programming in a language fun? Examples: I find it enjoyable to program in Ruby because of it's use of code blocks. It would be nice if you could include exactly one example in your answer Those features do not have to already exist in any language! I'm doing this because I have experienced extreme rises in (my own) productivity when programming in languages I love (because of particular features).

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  • Filling array with numbers

    - by Ockonal
    Hello, I have such situation: There is 8 div-blocks with ids like 'rateN_wrapper' where is 'N' is the number of div: <div id="rate1_wrapper"> <a href="#" id="0_1">...</a> <a href="#" id="0_2">...</a> <a href="#" id="0_3">...</a> </div> <div id="rate2_wrapper"> <a href="#" id="1_1">...</a> <a href="#" id="1_2">...</a> <a href="#" id="1_3">...</a> </div> ... var ratings = new Array(); for (i=0; i < 8; i++) { ratings[i] = -1; // Default is unrated } for (i=0; i < 8; i++) { $('#rate' + i + '_wrapper a').click(function() { ratings[i] = parseInt( $(this).attr('id').split('_')[1] ); console.debug(ratings); }); } My work is to fill array in need place with clicked link's id (parsed). But it's always changes only latest element of array (8). Why?

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  • How to access property in sub method after it runs?

    - by Warren
    I'm having a hard time working this one out but I think it should be pretty simple. Basically, I have this method which talks to a webservice and I need to return some data from the sub method, the "authCode". What am I doing wrong? How can I get the authCode out of the manager, or can I create a block or something to to ensure that the manager block runs first? Am I even using the right words - blocks, sub methods??? Please help :) - (NSString *)getAuthCodeEXAMPLE { __block NSString *returnString = @"nothing yet!"; NSURL *baseURL = [NSURL URLWithString:BaseURLString]; NSDictionary *parametersGetAuthCode = @{@"req": @"getauth"}; AFHTTPSessionManager *manager = [[AFHTTPSessionManager alloc] initWithBaseURL:baseURL]; manager.responseSerializer = [AFJSONResponseSerializer serializer]; [manager POST:APIscript parameters:parametersGetAuthCode success:^(NSURLSessionDataTask *task, id responseObject) { if ([task.response isKindOfClass:[NSHTTPURLResponse class]]) { NSHTTPURLResponse *r = (NSHTTPURLResponse *)task.response; if ([r statusCode] == 200) { self.returnedData = responseObject; NSString *authCode = [self.returnedData authcode]; NSLog(@"Authcode: %@", authCode); returnString = authCode; } } } failure:^(NSURLSessionDataTask *task, NSError *error) { UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:@"Error" message:[error localizedDescription] delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles:nil]; [alertView show]; }]; //this currently returns "nothing yet!" return returnString; }

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  • Dealing with large directories in a checkout

    - by Eric
    I am trying to come up with a version control process for a web app that I work on. Currently, my major stumbling blocks are two directories that are huge (both over 4GB). Only a few people need to work on things within the huge directories; most people don't even need to see what's in them. Our directory structure looks something like: / --file.aspx --anotherFile.aspx --/coolThings ----coolThing.aspx --/bigFolder ----someHugeMovie.mov ----someHugeSound.mp3 --/anotherBigFolder ----... I'm sure you get the picture. It's hard to justify a checkout that has to pull down 8GB of data that's likely useless to a developer. I know, it's only once, but even once could be really frustrating for someone (and will make it harder for me to convince everyone to use source control). (Plus, clean checkouts will be painfully slow.) These folders do have to be available in the web application. What can I do? I've thought about separate repositories for the big folders. That way, you only download if you need it; but then how do I manage checking these out onto our development server? I've also thought about not trying to version control those folders: just update them directly on the web server... but I am not enamored of this idea. Is there some magic way to simply exclude directories from a checkout that I haven't found? (Pretty sure there is not.) Of course, there's always the option to just give up, bite the bullet, and accept downloading 8 useless GB. What say you? Have you encountered this problem before? How did you solve it?

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  • bluetooth BluetoothSocket.connect() thread. how to close this thread

    - by Hia
    I am trying to make an android app that makes connection with bluetooth device. It works fine but when I call BluetoothSocket.connect() and it is not able to connect to devise its blocking. The thread and does not throw any exception. So when I try to close application while connect() is running its not responding. How can I cancel it? Used BluetoothSocket.close() in ... but still its not working for me. protected void simpleComm(Integer port) { // The documents tell us to cancel the discovery process. try { Method m = mmDevice.getClass().getMethod("createRfcommSocket", new Class[] { int.class }); mmSocket = (BluetoothSocket) m.invoke(mmDevice, port); mmSocket.connect(); // <== blocks untill is not connected Log.d(TAG, " connection success==="); }catch(Exception e){ if (!abort) { connectionFailed(); // Close the socket try { mmSocket.close(); // Start the service over to restart listening mode BluetoothService.this.start(); } catch (IOException e2) { Log.e(TAG,"unable to close() socket during connection failure", e2); } } return; } } public void cancel() { try { abort = true; mmSocket.close(); } catch (IOException e) { Log.e(TAG, "close() of connect socket failed", e); } }

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  • Changing Value of Array Pointer When Passed to a Function

    - by ZAX
    I have a function which receives both the array, and a specific instance of the array. I try to change the specific instance of the array by accessing one of its members "color", but it does not actually change it, as can be seen by debugging (checking the value of color after function runs in the main program). I am hoping someone can help me to access this member and change it. Essentially I need the instance of the array I'm specifying to be passed by reference if nothing else, but I'm hoping there is an easier way to accomplish what I'm trying to do. Here's the structures: typedef struct adjEdge{ int vertex; struct adjEdge *next; } adjEdge; typedef struct vertex{ int sink; int source; int color; //0 will be white, 1 will be grey, 5 will be black int number; adjEdge *nextVertex; } vertex; And here is the function: void walk(vertex *vertexArray, vertex v, int source, maxPairing *head) { int i; adjEdge *traverse; int moveVertex; int sink; traverse = vertexArray[v.number-1].nextVertex; if(v.color != 5 && v.sink == 5) { sink = v.number; v.color = 5; addMaxPair(head, source, sink); } else { walk(vertexArray, vertexArray[traverse->vertex-1], source, head); } } In particular, v.color needs to be changed to a 5, that way later after recursion the if condition blocks it.

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  • Windows setevent processsing

    - by Waldorf
    I wonder how setevent is handled internally within Windows. I have the following situation Std::thread thread loop which executes while std::atomic == true Inside the loop is a waitforsingleObject which sleeps infinite in alertable state. A function stopThread() which does the following: - Clears the atomic bool - Calls Setevent on the event object - Calls thread.join This often hangs, I get the impression that setevent has still some work to do in the current thread, while join blocks the current thread. If I add an additional Boolean in the thread which is set after waitforsinlgleObject and I wait for this to be set before calling join() Everything seems to work ok. Code (error checking omitted here) Init code/declarations: HANDLE m_WakeupThreadEvent; std::atomic<bool> m_ReceiverEnabled; m_WakeupThreadEvent = CreateEvent(NULL, false, false, "RxThreadWakeupEvent" ); Thread code: while(m_ReceiverEnabled) { DWORD rslt = WaitForSingleObjectEx(m_WakeupThreadEvent, INFINITE, true); // Here some checking for rslt; } function code: m_ReceiverEnabled = true; SetEvent( m_WakeupThreadEvent ) m_Thread.join() Is there some explanation for this behavior ? I could not find any details about the operation of setEvent()

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  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

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  • HTG Reviews the CODE Keyboard: Old School Construction Meets Modern Amenities

    - by Jason Fitzpatrick
    There’s nothing quite as satisfying as the smooth and crisp action of a well built keyboard. If you’re tired of  mushy keys and cheap feeling keyboards, a well-constructed mechanical keyboard is a welcome respite from the $10 keyboard that came with your computer. Read on as we put the CODE mechanical keyboard through the paces. What is the CODE Keyboard? The CODE keyboard is a collaboration between manufacturer WASD Keyboards and Jeff Atwood of Coding Horror (the guy behind the Stack Exchange network and Discourse forum software). Atwood’s focus was incorporating the best of traditional mechanical keyboards and the best of modern keyboard usability improvements. In his own words: The world is awash in terrible, crappy, no name how-cheap-can-we-make-it keyboards. There are a few dozen better mechanical keyboard options out there. I’ve owned and used at least six different expensive mechanical keyboards, but I wasn’t satisfied with any of them, either: they didn’t have backlighting, were ugly, had terrible design, or were missing basic functions like media keys. That’s why I originally contacted Weyman Kwong of WASD Keyboards way back in early 2012. I told him that the state of keyboards was unacceptable to me as a geek, and I proposed a partnership wherein I was willing to work with him to do whatever it takes to produce a truly great mechanical keyboard. Even the ardent skeptic who questions whether Atwood has indeed created a truly great mechanical keyboard certainly can’t argue with the position he starts from: there are so many agonizingly crappy keyboards out there. Even worse, in our opinion, is that unless you’re a typist of a certain vintage there’s a good chance you’ve never actually typed on a really nice keyboard. Those that didn’t start using computers until the mid-to-late 1990s most likely have always typed on modern mushy-key keyboards and never known the joy of typing on a really responsive and crisp mechanical keyboard. Is our preference for and love of mechanical keyboards shining through here? Good. We’re not even going to try and hide it. So where does the CODE keyboard stack up in pantheon of keyboards? Read on as we walk you through the simple setup and our experience using the CODE. Setting Up the CODE Keyboard Although the setup of the CODE keyboard is essentially plug and play, there are two distinct setup steps that you likely haven’t had to perform on a previous keyboard. Both highlight the degree of care put into the keyboard and the amount of customization available. Inside the box you’ll find the keyboard, a micro USB cable, a USB-to-PS2 adapter, and a tool which you may be unfamiliar with: a key puller. We’ll return to the key puller in a moment. Unlike the majority of keyboards on the market, the cord isn’t permanently affixed to the keyboard. What does this mean for you? Aside from the obvious need to plug it in yourself, it makes it dead simple to repair your own keyboard cord if it gets attacked by a pet, mangled in a mechanism on your desk, or otherwise damaged. It also makes it easy to take advantage of the cable routing channels in on the underside of the keyboard to  route your cable exactly where you want it. While we’re staring at the underside of the keyboard, check out those beefy rubber feet. By peripherals standards they’re huge (and there is six instead of the usual four). Once you plunk the keyboard down where you want it, it might as well be glued down the rubber feet work so well. After you’ve secured the cable and adjusted it to your liking, there is one more task  before plug the keyboard into the computer. On the bottom left-hand side of the keyboard, you’ll find a small recess in the plastic with some dip switches inside: The dip switches are there to switch hardware functions for various operating systems, keyboard layouts, and to enable/disable function keys. By toggling the dip switches you can change the keyboard from QWERTY mode to Dvorak mode and Colemak mode, the two most popular alternative keyboard configurations. You can also use the switches to enable Mac-functionality (for Command/Option keys). One of our favorite little toggles is the SW3 dip switch: you can disable the Caps Lock key; goodbye accidentally pressing Caps when you mean to press Shift. You can review the entire dip switch configuration chart here. The quick-start for Windows users is simple: double check that all the switches are in the off position (as seen in the photo above) and then simply toggle SW6 on to enable the media and backlighting function keys (this turns the menu key on the keyboard into a function key as typically found on laptop keyboards). After adjusting the dip switches to your liking, plug the keyboard into an open USB port on your computer (or into your PS/2 port using the included adapter). Design, Layout, and Backlighting The CODE keyboard comes in two flavors, a traditional 87-key layout (no number pad) and a traditional 104-key layout (number pad on the right hand side). We identify the layout as traditional because, despite some modern trapping and sneaky shortcuts, the actual form factor of the keyboard from the shape of the keys to the spacing and position is as classic as it comes. You won’t have to learn a new keyboard layout and spend weeks conditioning yourself to a smaller than normal backspace key or a PgUp/PgDn pair in an unconventional location. Just because the keyboard is very conventional in layout, however, doesn’t mean you’ll be missing modern amenities like media-control keys. The following additional functions are hidden in the F11, F12, Pause button, and the 2×6 grid formed by the Insert and Delete rows: keyboard illumination brightness, keyboard illumination on/off, mute, and then the typical play/pause, forward/backward, stop, and volume +/- in Insert and Delete rows, respectively. While we weren’t sure what we’d think of the function-key system at first (especially after retiring a Microsoft Sidewinder keyboard with a huge and easily accessible volume knob on it), it took less than a day for us to adapt to using the Fn key, located next to the right Ctrl key, to adjust our media playback on the fly. Keyboard backlighting is a largely hit-or-miss undertaking but the CODE keyboard nails it. Not only does it have pleasant and easily adjustable through-the-keys lighting but the key switches the keys themselves are attached to are mounted to a steel plate with white paint. Enough of the light reflects off the interior cavity of the keys and then diffuses across the white plate to provide nice even illumination in between the keys. Highlighting the steel plate beneath the keys brings us to the actual construction of the keyboard. It’s rock solid. The 87-key model, the one we tested, is 2.0 pounds. The 104-key is nearly a half pound heavier at 2.42 pounds. Between the steel plate, the extra-thick PCB board beneath the steel plate, and the thick ABS plastic housing, the keyboard has very solid feel to it. Combine that heft with the previously mentioned thick rubber feet and you have a tank-like keyboard that won’t budge a millimeter during normal use. Examining The Keys This is the section of the review the hardcore typists and keyboard ninjas have been waiting for. We’ve looked at the layout of the keyboard, we’ve looked at the general construction of it, but what about the actual keys? There are a wide variety of keyboard construction techniques but the vast majority of modern keyboards use a rubber-dome construction. The key is floated in a plastic frame over a rubber membrane that has a little rubber dome for each key. The press of the physical key compresses the rubber dome downwards and a little bit of conductive material on the inside of the dome’s apex connects with the circuit board. Despite the near ubiquity of the design, many people dislike it. The principal complaint is that dome keyboards require a complete compression to register a keystroke; keyboard designers and enthusiasts refer to this as “bottoming out”. In other words, the register the “b” key, you need to completely press that key down. As such it slows you down and requires additional pressure and movement that, over the course of tens of thousands of keystrokes, adds up to a whole lot of wasted time and fatigue. The CODE keyboard features key switches manufactured by Cherry, a company that has manufactured key switches since the 1960s. Specifically the CODE features Cherry MX Clear switches. These switches feature the same classic design of the other Cherry switches (such as the MX Blue and Brown switch lineups) but they are significantly quieter (yes this is a mechanical keyboard, but no, your neighbors won’t think you’re firing off a machine gun) as they lack the audible click found in most Cherry switches. This isn’t to say that they keyboard doesn’t have a nice audible key press sound when the key is fully depressed, but that the key mechanism isn’t doesn’t create a loud click sound when triggered. One of the great features of the Cherry MX clear is a tactile “bump” that indicates the key has been compressed enough to register the stroke. For touch typists the very subtle tactile feedback is a great indicator that you can move on to the next stroke and provides a welcome speed boost. Even if you’re not trying to break any word-per-minute records, that little bump when pressing the key is satisfying. The Cherry key switches, in addition to providing a much more pleasant typing experience, are also significantly more durable than dome-style key switch. Rubber dome switch membrane keyboards are typically rated for 5-10 million contacts whereas the Cherry mechanical switches are rated for 50 million contacts. You’d have to write the next War and Peace  and follow that up with A Tale of Two Cities: Zombie Edition, and then turn around and transcribe them both into a dozen different languages to even begin putting a tiny dent in the lifecycle of this keyboard. So what do the switches look like under the classicly styled keys? You can take a look yourself with the included key puller. Slide the loop between the keys and then gently beneath the key you wish to remove: Wiggle the key puller gently back and forth while exerting a gentle upward pressure to pop the key off; You can repeat the process for every key, if you ever find yourself needing to extract piles of cat hair, Cheeto dust, or other foreign objects from your keyboard. There it is, the naked switch, the source of that wonderful crisp action with the tactile bump on each keystroke. The last feature worthy of a mention is the N-key rollover functionality of the keyboard. This is a feature you simply won’t find on non-mechanical keyboards and even gaming keyboards typically only have any sort of key roller on the high-frequency keys like WASD. So what is N-key rollover and why do you care? On a typical mass-produced rubber-dome keyboard you cannot simultaneously press more than two keys as the third one doesn’t register. PS/2 keyboards allow for unlimited rollover (in other words you can’t out type the keyboard as all of your keystrokes, no matter how fast, will register); if you use the CODE keyboard with the PS/2 adapter you gain this ability. If you don’t use the PS/2 adapter and use the native USB, you still get 6-key rollover (and the CTRL, ALT, and SHIFT don’t count towards the 6) so realistically you still won’t be able to out type the computer as even the more finger twisting keyboard combos and high speed typing will still fall well within the 6-key rollover. The rollover absolutely doesn’t matter if you’re a slow hunt-and-peck typist, but if you’ve read this far into a keyboard review there’s a good chance that you’re a serious typist and that kind of quality construction and high-number key rollover is a fantastic feature.  The Good, The Bad, and the Verdict We’ve put the CODE keyboard through the paces, we’ve played games with it, typed articles with it, left lengthy comments on Reddit, and otherwise used and abused it like we would any other keyboard. The Good: The construction is rock solid. In an emergency, we’re confident we could use the keyboard as a blunt weapon (and then resume using it later in the day with no ill effect on the keyboard). The Cherry switches are an absolute pleasure to type on; the Clear variety found in the CODE keyboard offer a really nice middle-ground between the gun-shot clack of a louder mechanical switch and the quietness of a lesser-quality dome keyboard without sacrificing quality. Touch typists will love the subtle tactile bump feedback. Dip switch system makes it very easy for users on different systems and with different keyboard layout needs to switch between operating system and keyboard layouts. If you’re investing a chunk of change in a keyboard it’s nice to know you can take it with you to a different operating system or “upgrade” it to a new layout if you decide to take up Dvorak-style typing. The backlighting is perfect. You can adjust it from a barely-visible glow to a blazing light-up-the-room brightness. Whatever your intesity preference, the white-coated steel backplate does a great job diffusing the light between the keys. You can easily remove the keys for cleaning (or to rearrange the letters to support a new keyboard layout). The weight of the unit combined with the extra thick rubber feet keep it planted exactly where you place it on the desk. The Bad: While you’re getting your money’s worth, the $150 price tag is a shock when compared to the $20-60 price tags you find on lower-end keyboards. People used to large dedicated media keys independent of the traditional key layout (such as the large buttons and volume controls found on many modern keyboards) might be off put by the Fn-key style media controls on the CODE. The Verdict: The keyboard is clearly and heavily influenced by the needs of serious typists. Whether you’re a programmer, transcriptionist, or just somebody that wants to leave the lengthiest article comments the Internet has ever seen, the CODE keyboard offers a rock solid typing experience. Yes, $150 isn’t pocket change, but the quality of the CODE keyboard is so high and the typing experience is so enjoyable, you’re easily getting ten times the value you’d get out of purchasing a lesser keyboard. Even compared to other mechanical keyboards on the market, like the Das Keyboard, you’re still getting more for your money as other mechanical keyboards don’t come with the lovely-to-type-on Cherry MX Clear switches, back lighting, and hardware-based operating system keyboard layout switching. If it’s in your budget to upgrade your keyboard (especially if you’ve been slogging along with a low-end rubber-dome keyboard) there’s no good reason to not pickup a CODE keyboard. Key animation courtesy of Geekhack.org user Lethal Squirrel.       

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  • Stop Spinning Your Wheels&hellip; Sage Advice for Aspiring Developers

    - by Mark Rackley
    So… lately I’ve been tasked with helping bring some non-developers over the hump and become full-fledged, all around, SharePoint developers. Well, only time will tell if I’m successful or a complete failure. Good thing about failures though, you know what NOT to do next time! Anyway, I’ve been writing some sort of code since I was about 10 years old; so I sometimes take for granted the effort some people have to go through to learn a new technology. I guess if I had to say I was an “expert” in one thing it would be learning (and getting “stuff” done) in new technologies. Maybe that’s why I’ve embraced SharePoint and the SharePoint community. SharePoint is the first technology I haven’t been able to master or get everything done without help from other people. I KNOW I’ll never know it all and I learn something new every day.  It keeps it interesting, it keeps me motivated, and keeps me involved. So, what some people may consider a downside of SharePoint, I definitely consider a plus. Crap.. I’m rambling. Where was I? Oh yeah… me trying to be helpful. Like I said, I am able to quickly and effectively pick up new languages, technology, etc. and put it to good use. Am I just brilliant? Well, my mom thinks so.. but maybe not. Maybe I’ve just been doing it for a long time…. 25 years in some form or fashion… wow I’m old… Anyway, what I lack in depth I make up for in breadth and being the “go-to” guy wherever I work when someone needs to “get stuff done”.  Let’s see if I can take some of that experience and put it to practical use to help new people get up to speed faster, learn things more effectively, and become that go-to guy. First off…  make sure you… Know The Basics I don’t have the time to teach new developers the basics, but you gotta know them. I’ve only been “taught” two languages.. Fortran 77 and C… everything else I’ve picked up from “doing”. I HAD to know the basics though, and all new developers need to understand the very basics of development.  97.23% of all languages will have the following: Variables Functions Arrays If statements For loops / While loops If you think about it, most development is “if this, do this… or while this, do this…”.  “This” may be some unique method to your language or something you develop, but the basics are the basics. YES there are MANY other development topics you need to understand, but you shouldn’t be scratching your head trying to figure out what a ”for loop” is… (Also learn about classes and hashtables as quickly as possible). Once you have the basics down it makes it much easier to… Learn By Doing This may just apply to me and my warped brain.  I don’t learn a new technology by reading or hearing someone speak about it. I learn by doing. It does me no good to try and learn all of the intricacies of a new language or technology inside-and-out before getting my hands dirty. Just show me how to do one thing… let me get that working… then show me how to do the next thing.. let me get that working… Now, let’s see what I can figure out on my own. Okay.. now it starts to make sense. I see how the language works, I can step through the code, and before you know it.. I’m productive in a new technology. Be careful here though…. make sure you… Don’t Reinvent The Wheel People have been writing code for what… 50+ years now? So, why are you trying to tackle ANYTHING without first Googling it with Bing to see what others have done first? When I was first learning C# (I had come from a Java background) I had to call a web service.  Sure! No problem! I’d done this many times in Java. So, I proceeded to write an HTTP Handler, called the Web Service and it worked like a charm!!!  Probably about 2.3 seconds after I got it working completely someone says to me “Why didn’t you just add a Web Reference?” Really? You can do that?  oops… I just wasted a lot of time. Before undertaking the development of any sort of utility method in a new language, make sure it’s not already handled for you… Okay… you are starting to write some code and are curious about the possibilities? Well… don’t just sit there… Try It And See What Happens This is actually one of my biggest pet peeves. “So… ‘x++’ works in C#, but does it also work in JavaScript?”   Really? Did you just ask me that? In the time it spent for you to type that email, press the send button, me receive the email, get around to reading it, and replying with “yes” you could have tested it 47 times and know the answer! Just TRY it! See what happens! You aren’t doing brain surgery. You aren’t going to kill anyone, and you BETTER not be developing in production. So, you are not going to crash any production systems!! Seriously! Get off your butt and just try it yourself. The extra added benefit is that it doesn’t work, the absolute best way to learn is to… Learn From Your Failures I don’t know about you… but if I screw up and something doesn’t work, I learn A LOT more debugging my problem than if everything magically worked. It’s okay that you aren’t perfect! Not everyone can be me? In the same vein… don’t ask someone else to debug your problem until you have made a valiant attempt to do so yourself. There’s nothing quite like stepping through code line by line to see what it’s REALLY doing… and you’ll never feel more stupid sometimes than when you realize WHY it’s not working.. but you realize... you learn... and you remember. There is nothing wrong with failure as long as you learn from it. As you start writing more and more and more code make sure that you ALWAYS… Develop for Production You will soon learn that the “prototype” you wrote last week to show as a “proof of concept” is going to go directly into production no matter how much you beg and plead and try to explain it’s not ready to go into production… it’s going to go straight there.. and it’s like herpes.. it doesn’t go away and there’s no fixing it once it’s in there.  So, why not write ALL your code like it will be put in production? It MIGHT take a little longer, but in the long run it will be easier to maintain, get help on, and you won’t be embarrassed that it’s sitting on a production server for everyone to use and see. So, now that you are getting comfortable and writing code for production it is important to to remember the… KISS Principle… Learn It… Love It… Keep It Simple Stupid Seriously.. don’t try to show how smart you are by writing the most complicated code in history. Break your problem up into discrete steps and write each step. If it turns out you have some redundancy, you can always go back and tweak your code later.  How bad is it when you write code that LOOKS cocky? I’ve seen it before… some of the most abstract and complicated classes when a class wasn’t even needed! Or the most elaborate unreadable code jammed into one really long line when it could have been written in three lines, performed just as well, and been SOOO much easier to maintain. Keep it clear and simple.. baby steps people. This will help you learn the technology, debug problems, AND it will help others help you find your problems if they don’t have to decipher the Dead Sea Scrolls just to figure out what you are trying to do…. Really.. don’t be that guy… try to curb your ego and… Keep an Open Mind No matter how smart you are… how fast you type… or how much you get paid, don’t let your ego get in the way. There is probably a better way to do everything you’ve ever done. Don’t become so cocky that you can’t think someone knows more than you. There’s a lot of brilliant, helpful people out there willing to show you tricks if you just give them a chance. A very super-awesome developer once told me “So what if you’ve been writing code for 10 years or more! Does your code look basically the same? Are you not growing as a developer?” Those 10 years become pretty meaningless if you just “know” that you are right and have not picked up new tips, tricks, methods, and patterns along the way. Learn from others and find out what’s new in development land (you know you don’t have to specifically use pointers anymore??). Along those same lines… If it’s not working, first assume you are doing something wrong. You have no idea how much it annoys people who are trying to help you when you first assume that the help they are trying to give you is wrong. Just MAYBE… you… the person learning is making some small mistake? Maybe you didn’t describe your problem correctly? Maybe you are using the wrong terminology? “I did exactly what you said and it didn’t work.”  Oh really? Are you SURE about that? “Your solution doesn’t work.”  Well… I’m pretty sure it works, I’ve used it 200 times… What are you doing differently? First try some humility and appreciation.. it will go much further, especially when it turns out YOU are the one that is wrong. When all else fails…. Try Professional Training Some people just don’t have the mindset to go and figure stuff out. It’s a gift and not everyone has it. If everyone could do it I wouldn’t have a job and there wouldn’t be professional training available.  So, if you’ve tried everything else and no light bulbs are coming on, contact the experts who specialize in training. Be careful though, there is bad training out there. Want to know the names of some good places? Just shoot me a message and I’ll let you know. I’m boycotting endorsing Andrew Connell anymore until I get that free course dangit!! So… that’s it.. that’s all I got right now. Maybe you thought all of this is common sense, maybe you think I’m smoking crack. If so, don’t just sit there, there’s a comments section for a reason. Finally, what about you? What tips do you have to help this aspiring to learn the dark arts??

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  • ASPNET WebAPI REST Guidance

    - by JoshReuben
    ASP.NET Web API is an ideal platform for building RESTful applications on the .NET Framework. While I may be more partial to NodeJS these days, there is no denying that WebAPI is a well engineered framework. What follows is my investigation of how to leverage WebAPI to construct a RESTful frontend API.   The Advantages of REST Methodology over SOAP Simpler API for CRUD ops Standardize Development methodology - consistent and intuitive Standards based à client interop Wide industry adoption, Ease of use à easy to add new devs Avoid service method signature blowout Smaller payloads than SOAP Stateless à no session data means multi-tenant scalability Cache-ability Testability   General RESTful API Design Overview · utilize HTTP Protocol - Usage of HTTP methods for CRUD, standard HTTP response codes, common HTTP headers and Mime Types · Resources are mapped to URLs, actions are mapped to verbs and the rest goes in the headers. · keep the API semantic, resource-centric – A RESTful, resource-oriented service exposes a URI for every piece of data the client might want to operate on. A REST-RPC Hybrid exposes a URI for every operation the client might perform: one URI to fetch a piece of data, a different URI to delete that same data. utilize Uri to specify CRUD op, version, language, output format: http://api.MyApp.com/{ver}/{lang}/{resource_type}/{resource_id}.{output_format}?{key&filters} · entity CRUD operations are matched to HTTP methods: · Create - POST / PUT · Read – GET - cacheable · Update – PUT · Delete - DELETE · Use Uris to represent a hierarchies - Resources in RESTful URLs are often chained · Statelessness allows for idempotency – apply an op multiple times without changing the result. POST is non-idempotent, the rest are idempotent (if DELETE flags records instead of deleting them). · Cache indication - Leverage HTTP headers to label cacheable content and indicate the permitted duration of cache · PUT vs POST - The client uses PUT when it determines which URI (Id key) the new resource should have. The client uses POST when the server determines they key. PUT takes a second param – the id. POST creates a new resource. The server assigns the URI for the new object and returns this URI as part of the response message. Note: The PUT method replaces the entire entity. That is, the client is expected to send a complete representation of the updated product. If you want to support partial updates, the PATCH method is preferred DELETE deletes a resource at a specified URI – typically takes an id param · Leverage Common HTTP Response Codes in response headers 200 OK: Success 201 Created - Used on POST request when creating a new resource. 304 Not Modified: no new data to return. 400 Bad Request: Invalid Request. 401 Unauthorized: Authentication. 403 Forbidden: Authorization 404 Not Found – entity does not exist. 406 Not Acceptable – bad params. 409 Conflict - For POST / PUT requests if the resource already exists. 500 Internal Server Error 503 Service Unavailable · Leverage uncommon HTTP Verbs to reduce payload sizes HEAD - retrieves just the resource meta-information. OPTIONS returns the actions supported for the specified resource. PATCH - partial modification of a resource. · When using PUT, POST or PATCH, send the data as a document in the body of the request. Don't use query parameters to alter state. · Utilize Headers for content negotiation, caching, authorization, throttling o Content Negotiation – choose representation (e.g. JSON or XML and version), language & compression. Signal via RequestHeader.Accept & ResponseHeader.Content-Type Accept: application/json;version=1.0 Accept-Language: en-US Accept-Charset: UTF-8 Accept-Encoding: gzip o Caching - ResponseHeader: Expires (absolute expiry time) or Cache-Control (relative expiry time) o Authorization - basic HTTP authentication uses the RequestHeader.Authorization to specify a base64 encoded string "username:password". can be used in combination with SSL/TLS (HTTPS) and leverage OAuth2 3rd party token-claims authorization. Authorization: Basic sQJlaTp5ZWFslylnaNZ= o Rate Limiting - Not currently part of HTTP so specify non-standard headers prefixed with X- in the ResponseHeader. X-RateLimit-Limit: 10000 X-RateLimit-Remaining: 9990 · HATEOAS Methodology - Hypermedia As The Engine Of Application State – leverage API as a state machine where resources are states and the transitions between states are links between resources and are included in their representation (hypermedia) – get API metadata signatures from the response Link header - in a truly REST based architecture any URL, except the initial URL, can be changed, even to other servers, without worrying about the client. · error responses - Do not just send back a 200 OK with every response. Response should consist of HTTP error status code (JQuery has automated support for this), A human readable message , A Link to a meaningful state transition , & the original data payload that was problematic. · the URIs will typically map to a server-side controller and a method name specified by the type of request method. Stuff all your calls into just four methods is not as crazy as it sounds. · Scoping - Path variables look like you’re traversing a hierarchy, and query variables look like you’re passing arguments into an algorithm · Mapping URIs to Controllers - have one controller for each resource is not a rule – can consolidate - route requests to the appropriate controller and action method · Keep URls Consistent - Sometimes it’s tempting to just shorten our URIs. not recommend this as this can cause confusion · Join Naming – for m-m entity relations there may be multiple hierarchy traversal paths · Routing – useful level of indirection for versioning, server backend mocking in development ASPNET WebAPI Considerations ASPNET WebAPI implements a lot (but not all) RESTful API design considerations as part of its infrastructure and via its coding convention. Overview When developing an API there are basically three main steps: 1. Plan out your URIs 2. Setup return values and response codes for your URIs 3. Implement a framework for your API.   Design · Leverage Models MVC folder · Repositories – support IoC for tests, abstraction · Create DTO classes – a level of indirection decouples & allows swap out · Self links can be generated using the UrlHelper · Use IQueryable to support projections across the wire · Models can support restful navigation properties – ICollection<T> · async mechanism for long running ops - return a response with a ticket – the client can then poll or be pushed the final result later. · Design for testability - Test using HttpClient , JQuery ( $.getJSON , $.each) , fiddler, browser debug. Leverage IDependencyResolver – IoC wrapper for mocking · Easy debugging - IE F12 developer tools: Network tab, Request Headers tab     Routing · HTTP request method is matched to the method name. (This rule applies only to GET, POST, PUT, and DELETE requests.) · {id}, if present, is matched to a method parameter named id. · Query parameters are matched to parameter names when possible · Done in config via Routes.MapHttpRoute – similar to MVC routing · Can alternatively: o decorate controller action methods with HttpDelete, HttpGet, HttpHead,HttpOptions, HttpPatch, HttpPost, or HttpPut., + the ActionAttribute o use AcceptVerbsAttribute to support other HTTP verbs: e.g. PATCH, HEAD o use NonActionAttribute to prevent a method from getting invoked as an action · route table Uris can support placeholders (via curly braces{}) – these can support default values and constraints, and optional values · The framework selects the first route in the route table that matches the URI. Response customization · Response code: By default, the Web API framework sets the response status code to 200 (OK). But according to the HTTP/1.1 protocol, when a POST request results in the creation of a resource, the server should reply with status 201 (Created). Non Get methods should return HttpResponseMessage · Location: When the server creates a resource, it should include the URI of the new resource in the Location header of the response. public HttpResponseMessage PostProduct(Product item) {     item = repository.Add(item);     var response = Request.CreateResponse<Product>(HttpStatusCode.Created, item);     string uri = Url.Link("DefaultApi", new { id = item.Id });     response.Headers.Location = new Uri(uri);     return response; } Validation · Decorate Models / DTOs with System.ComponentModel.DataAnnotations properties RequiredAttribute, RangeAttribute. · Check payloads using ModelState.IsValid · Under posting – leave out values in JSON payload à JSON formatter assigns a default value. Use with RequiredAttribute · Over-posting - if model has RO properties à use DTO instead of model · Can hook into pipeline by deriving from ActionFilterAttribute & overriding OnActionExecuting Config · Done in App_Start folder > WebApiConfig.cs – static Register method: HttpConfiguration param: The HttpConfiguration object contains the following members. Member Description DependencyResolver Enables dependency injection for controllers. Filters Action filters – e.g. exception filters. Formatters Media-type formatters. by default contains JsonFormatter, XmlFormatter IncludeErrorDetailPolicy Specifies whether the server should include error details, such as exception messages and stack traces, in HTTP response messages. Initializer A function that performs final initialization of the HttpConfiguration. MessageHandlers HTTP message handlers - plug into pipeline ParameterBindingRules A collection of rules for binding parameters on controller actions. Properties A generic property bag. Routes The collection of routes. Services The collection of services. · Configure JsonFormatter for circular references to support links: PreserveReferencesHandling.Objects Documentation generation · create a help page for a web API, by using the ApiExplorer class. · The ApiExplorer class provides descriptive information about the APIs exposed by a web API as an ApiDescription collection · create the help page as an MVC view public ILookup<string, ApiDescription> GetApis()         {             return _explorer.ApiDescriptions.ToLookup(                 api => api.ActionDescriptor.ControllerDescriptor.ControllerName); · provide documentation for your APIs by implementing the IDocumentationProvider interface. Documentation strings can come from any source that you like – e.g. extract XML comments or define custom attributes to apply to the controller [ApiDoc("Gets a product by ID.")] [ApiParameterDoc("id", "The ID of the product.")] public HttpResponseMessage Get(int id) · GlobalConfiguration.Configuration.Services – add the documentation Provider · To hide an API from the ApiExplorer, add the ApiExplorerSettingsAttribute Plugging into the Message Handler pipeline · Plug into request / response pipeline – derive from DelegatingHandler and override theSendAsync method – e.g. for logging error codes, adding a custom response header · Can be applied globally or to a specific route Exception Handling · Throw HttpResponseException on method failures – specify HttpStatusCode enum value – examine this enum, as its values map well to typical op problems · Exception filters – derive from ExceptionFilterAttribute & override OnException. Apply on Controller or action methods, or add to global HttpConfiguration.Filters collection · HttpError object provides a consistent way to return error information in the HttpResponseException response body. · For model validation, you can pass the model state to CreateErrorResponse, to include the validation errors in the response public HttpResponseMessage PostProduct(Product item) {     if (!ModelState.IsValid)     {         return Request.CreateErrorResponse(HttpStatusCode.BadRequest, ModelState); Cookie Management · Cookie header in request and Set-Cookie headers in a response - Collection of CookieState objects · Specify Expiry, max-age resp.Headers.AddCookies(new CookieHeaderValue[] { cookie }); Internet Media Types, formatters and serialization · Defaults to application/json · Request Accept header and response Content-Type header · determines how Web API serializes and deserializes the HTTP message body. There is built-in support for XML, JSON, and form-urlencoded data · customizable formatters can be inserted into the pipeline · POCO serialization is opt out via JsonIgnoreAttribute, or use DataMemberAttribute for optin · JSON serializer leverages NewtonSoft Json.NET · loosely structured JSON objects are serialzed as JObject which derives from Dynamic · to handle circular references in json: json.SerializerSettings.PreserveReferencesHandling =    PreserveReferencesHandling.All à {"$ref":"1"}. · To preserve object references in XML [DataContract(IsReference=true)] · Content negotiation Accept: Which media types are acceptable for the response, such as “application/json,” “application/xml,” or a custom media type such as "application/vnd.example+xml" Accept-Charset: Which character sets are acceptable, such as UTF-8 or ISO 8859-1. Accept-Encoding: Which content encodings are acceptable, such as gzip. Accept-Language: The preferred natural language, such as “en-us”. o Web API uses the Accept and Accept-Charset headers. (At this time, there is no built-in support for Accept-Encoding or Accept-Language.) · Controller methods can take JSON representations of DTOs as params – auto-deserialization · Typical JQuery GET request: function find() {     var id = $('#prodId').val();     $.getJSON("api/products/" + id,         function (data) {             var str = data.Name + ': $' + data.Price;             $('#product').text(str);         })     .fail(         function (jqXHR, textStatus, err) {             $('#product').text('Error: ' + err);         }); }            · Typical GET response: HTTP/1.1 200 OK Server: ASP.NET Development Server/10.0.0.0 Date: Mon, 18 Jun 2012 04:30:33 GMT X-AspNet-Version: 4.0.30319 Cache-Control: no-cache Pragma: no-cache Expires: -1 Content-Type: application/json; charset=utf-8 Content-Length: 175 Connection: Close [{"Id":1,"Name":"TomatoSoup","Price":1.39,"ActualCost":0.99},{"Id":2,"Name":"Hammer", "Price":16.99,"ActualCost":10.00},{"Id":3,"Name":"Yo yo","Price":6.99,"ActualCost": 2.05}] True OData support · Leverage Query Options $filter, $orderby, $top and $skip to shape the results of controller actions annotated with the [Queryable]attribute. [Queryable]  public IQueryable<Supplier> GetSuppliers()  · Query: ~/Suppliers?$filter=Name eq ‘Microsoft’ · Applies the following selection filter on the server: GetSuppliers().Where(s => s.Name == “Microsoft”)  · Will pass the result to the formatter. · true support for the OData format is still limited - no support for creates, updates, deletes, $metadata and code generation etc · vnext: ability to configure how EditLinks, SelfLinks and Ids are generated Self Hosting no dependency on ASPNET or IIS: using (var server = new HttpSelfHostServer(config)) {     server.OpenAsync().Wait(); Tracing · tracability tools, metrics – e.g. send to nagios · use your choice of tracing/logging library, whether that is ETW,NLog, log4net, or simply System.Diagnostics.Trace. · To collect traces, implement the ITraceWriter interface public class SimpleTracer : ITraceWriter {     public void Trace(HttpRequestMessage request, string category, TraceLevel level,         Action<TraceRecord> traceAction)     {         TraceRecord rec = new TraceRecord(request, category, level);         traceAction(rec);         WriteTrace(rec); · register the service with config · programmatically trace – has helper extension methods: Configuration.Services.GetTraceWriter().Info( · Performance tracing - pipeline writes traces at the beginning and end of an operation - TraceRecord class includes aTimeStamp property, Kind property set to TraceKind.Begin / End Security · Roles class methods: RoleExists, AddUserToRole · WebSecurity class methods: UserExists, .CreateUserAndAccount · Request.IsAuthenticated · Leverage HTTP 401 (Unauthorized) response · [AuthorizeAttribute(Roles="Administrator")] – can be applied to Controller or its action methods · See section in WebApi document on "Claim-based-security for ASP.NET Web APIs using DotNetOpenAuth" – adapt this to STS.--> Web API Host exposes secured Web APIs which can only be accessed by presenting a valid token issued by the trusted issuer. http://zamd.net/2012/05/04/claim-based-security-for-asp-net-web-apis-using-dotnetopenauth/ · Use MVC membership provider infrastructure and add a DelegatingHandler child class to the WebAPI pipeline - http://stackoverflow.com/questions/11535075/asp-net-mvc-4-web-api-authentication-with-membership-provider - this will perform the login actions · Then use AuthorizeAttribute on controllers and methods for role mapping- http://sixgun.wordpress.com/2012/02/29/asp-net-web-api-basic-authentication/ · Alternate option here is to rely on MVC App : http://forums.asp.net/t/1831767.aspx/1

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  • ActiveMQ - "Cannot send, channel has already failed" every 2 seconds?

    - by quanta
    ActiveMQ 5.7.0 In the activemq.log, I'm seeing this exception every 2 seconds: 2013-11-05 13:00:52,374 | DEBUG | Transport Connection to: tcp://127.0.0.1:37501 failed: org.apache.activemq.transport.InactivityIOException: Cannot send, channel has already failed: tcp://127.0.0.1:37501 | org.apache.activemq.broker.TransportConnection.Transport | Async Exception Handler org.apache.activemq.transport.InactivityIOException: Cannot send, channel has already failed: tcp://127.0.0.1:37501 at org.apache.activemq.transport.AbstractInactivityMonitor.doOnewaySend(AbstractInactivityMonitor.java:282) at org.apache.activemq.transport.AbstractInactivityMonitor.oneway(AbstractInactivityMonitor.java:271) at org.apache.activemq.transport.TransportFilter.oneway(TransportFilter.java:85) at org.apache.activemq.transport.WireFormatNegotiator.oneway(WireFormatNegotiator.java:104) at org.apache.activemq.transport.MutexTransport.oneway(MutexTransport.java:68) at org.apache.activemq.broker.TransportConnection.dispatch(TransportConnection.java:1312) at org.apache.activemq.broker.TransportConnection.processDispatch(TransportConnection.java:838) at org.apache.activemq.broker.TransportConnection.iterate(TransportConnection.java:873) at org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:129) at org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:47) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) Due to this keyword InactivityIOException, the first thing comes to my mind is InactivityMonitor, but the strange thing is MaxInactivityDuration=30000: 2013-11-05 13:11:02,672 | DEBUG | Sending: WireFormatInfo { version=9, properties={MaxFrameSize=9223372036854775807, CacheSize=1024, CacheEnabled=true, SizePrefixDisabled=false, MaxInactivityDurationInitalDelay=10000, TcpNoDelayEnabled=true, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]} | org.apache.activemq.transport.WireFormatNegotiator | ActiveMQ BrokerService[localhost] Task-2 Moreover, I also didn't see something like this: No message received since last read check for ... or: Channel was inactive for too (30000) long Do a netstat, I see these connections in TIME_WAIT state: tcp 0 0 127.0.0.1:38545 127.0.0.1:61616 TIME_WAIT - tcp 0 0 127.0.0.1:38544 127.0.0.1:61616 TIME_WAIT - tcp 0 0 127.0.0.1:38522 127.0.0.1:61616 TIME_WAIT - Here're the output when running tcpdump: Internet Protocol Version 4, Src: 127.0.0.1 (127.0.0.1), Dst: 127.0.0.1 (127.0.0.1) Version: 4 Header length: 20 bytes Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport)) 0000 00.. = Differentiated Services Codepoint: Default (0x00) .... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00) Total Length: 296 Identification: 0x7b6a (31594) Flags: 0x02 (Don't Fragment) 0... .... = Reserved bit: Not set .1.. .... = Don't fragment: Set ..0. .... = More fragments: Not set Fragment offset: 0 Time to live: 64 Protocol: TCP (6) Header checksum: 0xc063 [correct] [Good: True] [Bad: False] Source: 127.0.0.1 (127.0.0.1) Destination: 127.0.0.1 (127.0.0.1) Transmission Control Protocol, Src Port: 61616 (61616), Dst Port: 54669 (54669), Seq: 1, Ack: 2, Len: 244 Source port: 61616 (61616) Destination port: 54669 (54669) [Stream index: 11] Sequence number: 1 (relative sequence number) [Next sequence number: 245 (relative sequence number)] Acknowledgement number: 2 (relative ack number) Header length: 32 bytes Flags: 0x018 (PSH, ACK) 000. .... .... = Reserved: Not set ...0 .... .... = Nonce: Not set .... 0... .... = Congestion Window Reduced (CWR): Not set .... .0.. .... = ECN-Echo: Not set .... ..0. .... = Urgent: Not set .... ...1 .... = Acknowledgement: Set .... .... 1... = Push: Set .... .... .0.. = Reset: Not set .... .... ..0. = Syn: Not set .... .... ...0 = Fin: Not set Window size value: 256 [Calculated window size: 32768] [Window size scaling factor: 128] Checksum: 0xff1c [validation disabled] [Good Checksum: False] [Bad Checksum: False] Options: (12 bytes) No-Operation (NOP) No-Operation (NOP) Timestamps: TSval 2304161892, TSecr 2304161891 Kind: Timestamp (8) Length: 10 Timestamp value: 2304161892 Timestamp echo reply: 2304161891 [SEQ/ACK analysis] [Bytes in flight: 244] Constrained Application Protocol, TID: 240, Length: 244 00.. .... = Version: 0 ..00 .... = Type: Confirmable (0) .... 0000 = Option Count: 0 Code: Unknown (0) Transaction ID: 240 Payload Content-Type: text/plain (default), Length: 240, offset: 4 Line-based text data: text/plain [truncated] \001ActiveMQ\000\000\000\t\001\000\000\000<DE>\000\000\000\t\000\fMaxFrameSize\006\177<FF><FF><FF><FF> <FF><FF><FF>\000\tCacheSize\005\000\000\004\000\000\fCacheEnabled\001\001\000\022SizePrefixDisabled\001\000\000 MaxInactivityDurationInitalDelay\006\ It is very likely a tcp port check. This is what I see when trying telnet from another host: 2013-11-05 16:12:41,071 | DEBUG | Transport Connection to: tcp://10.8.20.9:46775 failed: java.io.EOFException | org.apache.activemq.broker.TransportConnection.Transport | ActiveMQ Transport: tcp:///10.8.20.9:46775@61616 java.io.EOFException at java.io.DataInputStream.readInt(DataInputStream.java:375) at org.apache.activemq.openwire.OpenWireFormat.unmarshal(OpenWireFormat.java:275) at org.apache.activemq.transport.tcp.TcpTransport.readCommand(TcpTransport.java:229) at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:221) at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:204) at java.lang.Thread.run(Thread.java:662) 2013-11-05 16:12:41,071 | DEBUG | Transport Connection to: tcp://10.8.20.9:46775 failed: org.apache.activemq.transport.InactivityIOException: Cannot send, channel has already failed: tcp://10.8.20.9:46775 | org.apache.activemq.broker.TransportConnection.Transport | Async Exception Handler org.apache.activemq.transport.InactivityIOException: Cannot send, channel has already failed: tcp://10.8.20.9:46775 at org.apache.activemq.transport.AbstractInactivityMonitor.doOnewaySend(AbstractInactivityMonitor.java:282) at org.apache.activemq.transport.AbstractInactivityMonitor.oneway(AbstractInactivityMonitor.java:271) at org.apache.activemq.transport.TransportFilter.oneway(TransportFilter.java:85) at org.apache.activemq.transport.WireFormatNegotiator.oneway(WireFormatNegotiator.java:104) at org.apache.activemq.transport.MutexTransport.oneway(MutexTransport.java:68) at org.apache.activemq.broker.TransportConnection.dispatch(TransportConnection.java:1312) at org.apache.activemq.broker.TransportConnection.processDispatch(TransportConnection.java:838) at org.apache.activemq.broker.TransportConnection.iterate(TransportConnection.java:873) at org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:129) at org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:47) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:662) 2013-11-05 16:12:41,071 | DEBUG | Unregistering MBean org.apache.activemq:BrokerName=localhost,Type=Connection,ConnectorName=ope nwire,ViewType=address,Name=tcp_//10.8.20.9_46775 | org.apache.activemq.broker.jmx.ManagementContext | ActiveMQ Transport: tcp:/ //10.8.20.9:46775@61616 2013-11-05 16:12:41,073 | DEBUG | Stopping connection: tcp://10.8.20.9:46775 | org.apache.activemq.broker.TransportConnection | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,073 | DEBUG | Stopping transport tcp:///10.8.20.9:46775@61616 | org.apache.activemq.transport.tcp.TcpTranspo rt | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,073 | DEBUG | Initialized TaskRunnerFactory[ActiveMQ Task] using ExecutorService: java.util.concurrent.Threa dPoolExecutor@23cc2a28 | org.apache.activemq.thread.TaskRunnerFactory | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,074 | DEBUG | Closed socket Socket[addr=/10.8.20.9,port=46775,localport=61616] | org.apache.activemq.transpo rt.tcp.TcpTransport | ActiveMQ Task-1 2013-11-05 16:12:41,074 | DEBUG | Forcing shutdown of ExecutorService: java.util.concurrent.ThreadPoolExecutor@23cc2a28 | org.apache.activemq.util.ThreadPoolUtils | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,074 | DEBUG | Stopped transport: tcp://10.8.20.9:46775 | org.apache.activemq.broker.TransportConnection | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,074 | DEBUG | Connection Stopped: tcp://10.8.20.9:46775 | org.apache.activemq.broker.TransportConnection | ActiveMQ BrokerService[localhost] Task-5 2013-11-05 16:12:41,902 | DEBUG | Sending: WireFormatInfo { version=9, properties={MaxFrameSize=9223372036854775807, CacheSize=1024, CacheEnabled=true, SizePrefixDisabled=false, MaxInactivityDurationInitalDelay=10000, TcpNoDelayEnabled=true, MaxInactivityDuration=30000, TightEncodingEnabled=true, StackTraceEnabled=true}, magic=[A,c,t,i,v,e,M,Q]} | org.apache.activemq.transport.WireFormatNegotiator | ActiveMQ BrokerService[localhost] Task-5 So the question is: how can I find out the process that is trying to connect to my ActiveMQ (from localhost) every 2 seconds?

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  • WCF Maximum message size quota exceeded problem - Guru needed

    - by Rire1979
    The maximum message size quota for incoming messages (65536) has been exceeded. To increase the quota, use the MaxReceivedMessageSize property on the appropriate binding element. Let me begin by saying that I can fix the problem by increasing the size of MaxReceivedMessageSize and the appropriate buffer. However it looks to me that this solution is not ideal because it's impossible to establish an upper bound to the size of the message as data changes daily. Setting it to the maximum size of two gigs feels like the wrong approach ... It may matter... or not: I'm using the MSN ad center API v6. Can an experienced WCF professional confirm this is indeed the approach we'll have to make do with? Is it as bad as it looks? Thank you.

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  • DES3 decryption in Ruby on Rails

    - by AntonAL
    My RoR server receives a string, that was encrypted in C++ application using des3 with base64 encoding The cipher object is created so: cipher = OpenSSL::Cipher::Cipher::new("des3") cipher.key = key_str cipher.iv = iv_str key_str and iv_str: are string representations of key and initialization vector for encryption algorithm. They are the same for RoR and C++ application. The code on the RoR side is following: result = "" result << cipher.update( Base64.decode64(message) ) result << cipher.final After executing the last line of code, i get an exception OpenSSL::CipherError (bad decrypt) What is wrong here ? Any ideas ?

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  • Db2 error : SQL0901N, SQLSTATE=58004

    - by Harv
    Hi, Can i use Atomic in the parrent procedure as well as in the procedure which the mail procedure calls. My procedure compiles perfectly, but sometimes when I execute it. I receive following error: DB2 Database Error: ERROR [58004] [IBM][DB2/NT64] SQL0901N The SQL statement failed because of a non-severe system error. Subsequent SQL statements can be processed. (Reason "Sdir len bad: 1542!=1520+14".) SQLSTATE=58004 However, surprisingly when i commented the "ATOMIC" keyword in the main procedure and ran again it ran perfectly. But when I ran it again after uncommenting it still did not give any errors and ran perfectly. So the error that I recieve is not something that I recive everytime.Could some one please let me know what could be the issue and what needs to be done to resolve this. As on goolgeing I did not find any leads on this. Thanks, Harveer

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