Search Results

Search found 17187 results on 688 pages for 'give me chicken'.

Page 40/688 | < Previous Page | 36 37 38 39 40 41 42 43 44 45 46 47  | Next Page >

  • Want to show file association icon and skype like progress bar c#

    - by Thomas
    whenever user drag any file onto skype chat textbox then skype show right icon for that file and one custom progress bar rounded corner. i have 4 questions 1) i am working with win application not WPF. i like to know how to develop skype like corner progressbar. i search lot google to find out skype like progressbar. so if anyone knows how to develop that kind of progress bar then please share that knowledge or give me any url from where i can download similar look progressbar. 2) when i drag any file onto my richtextbox then how could i show right icon for that file on my richtextbox. anyone can give me idea. 3) what kind of richtextbox skype use? is there any advance richtextbox library which i can use for showing picture or button etc. 4) skype shows button on chat textbox called Cancel......is it button or any image. when user click on that button then button respond accordingly. so just tell me how could place any button on my rich textbox and when i will click on that button then a event should fire at my end. any idea. here i attach a picture from where you can see the image of progressbar that i am looking for. how i want to show the progress button and file associated icon on richtextbox. the object behind attaching the image is other person can understand what is my requirement and what i want to know. please anyone give me the idea for my above 4 points. thanks

    Read the article

  • Concatenate CLOB-rows with PL/SQL

    - by david K
    Hi, I've got a table which has an id and a clob content like: Create Table v_example_l ( nip number, xmlcontent clob ); We insert our data: Insert into V_EXAMPLE_L (NIP,XMLCONTENT) Values (17852,'<section><block><name>delta</name><content>548484646846484</content></block></section>'); Insert into V_EXAMPLE_L (NIP,XMLCONTENT) Values (17852,'<section><block><name>omega</name><content>545648468484</content></block></section>'); Insert into V_EXAMPLE_L (NIP,XMLCONTENT) Values (17852,'<section><block><name>gamma</name><content>54564846qsdqsdqsdqsd8484</content></block></section>'); I'm trying to do a function that concatenates the rows of the clob that gone be the result of a select, i mean without having to give multiple parameter about the name of table or such, i should only give here the column that contain the clobs, and it should handle the rest. CREATE OR REPLACE function assemble_clob(q varchar2) return clob is v_clob clob; tmp_lob clob; hold VARCHAR2(4000); --cursor c2 is select xmlcontent from V_EXAMPLE_L where id=17852 cur sys_refcursor; begin OPEN cur FOR q; LOOP FETCH cur INTO tmp_lob; EXIT WHEN cur%NOTFOUND; --v_clob := v_clob || XMLTYPE.getClobVal(tmp_lob.xmlcontent); v_clob := v_clob || tmp_lob; END LOOP; return (v_clob); --return (dbms_xmlquery.getXml( dbms_xmlquery.set_context("Select 1 from dual")) ) end assemble_clob; The function is broken... (if anybody could give me a help, thanks a lot, and i'm noob in sql so ....). Thanks!

    Read the article

  • Modeling complex hierarchies

    - by jdn
    To gain some experience, I am trying to make an expert system that can answer queries about the animal kingdom. However, I have run into a problem modeling the domain. I originally considered the animal kingdom hierarchy to be drawn like -animal -bird -carnivore -hawk -herbivore -bluejay -mammals -carnivores -herbivores This I figured would allow me to make queries easily like "give me all birds", but would be much more expensive to say "give me all carnivores", so I rewrote the hierarchy to look like: -animal -carnivore -birds -hawk -mammals -xyz -herbivores -birds -bluejay -mammals But now it will be much slower to query "give me all birds." This is of course a simple example, but it got me thinking that I don't really know how to model complex relationships that are not so strictly hierarchical in nature in the context of writing an expert system to answer queries as stated above. A directed, cyclic graph seems like it could mathematically solve the problem, but storing this in a relational database and maintaining it (updates) would seem like a nightmare to me. I would like to know how people typically model such things. Explanations or pointers to resources to read further would be acceptable and appreciated.

    Read the article

  • msbuild/clickonce publish files generated during the build

    - by Anonym
    As a part of my build process I generate some files that should be included when creating a clickonce deployment. Here is a blog post of someone telling you how to include items that's not part of the project. However, as someone mentions in the comments of that blogpost, it won't update the deploymentmanifest when you do it in the "BeforePublish" task and the files won't get downloaded - it works fine if you do it in the "BeforeBuild" task though. This gives me a chicken and egg problem as I have to perform the build first to generate the files I want included.. Does anyone have a solution for this ? (p.s. at the moment generating the clickonce deployment using mage.exe is not an option, it have to be done using the Publish target)

    Read the article

  • Store the cache data locally

    - by Lu Lu
    Hello, I develops a C# Winform application, it is a client and connect to web service to get data. The data returned by webservice is a DataTable. Client will display it on a DataGridView. My problem is that: Client will take more time to get all data from server (web service is not local with client). So I must to use a thread to get data. This is my model: Client create a thread to get data - thread complete and send event to client - client display data on datagridview on a form. However, when user closes the form, user can open this form in another time, and client must get data again. This solution will cause the client slowly. So, I think about a cached data: Client <---get/add/edit/delete--- Cached Data ---get/add/edit/delete---Server (web service) Please give me some suggestions. Example: cached data should be developed in another application which is same host with client? Or cached data is running in client. Please give me some techniques to implement this solution. If having any examples, please give me. Thanks.

    Read the article

  • java servlet:response.sendRedirect() not giving illegal state exception if called after commit of re

    - by sahil garg
    after commit of response as here redirect statement should give exception but it is not doing so if this redirect statemnet is in if block.but it does give exception in case it is out of if block.i have shown same statement(with marked stars ) at two places below.can u please tell me reason for it. protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub synchronized (noOfRequests) { noOfRequests++; } PrintWriter pw=null; response.setContentType("text/html"); response.setHeader("foo","bar"); //response is commited because of above statement pw=response.getWriter(); pw.print("hello : "+noOfRequests); //if i remove below statement this same statement is present in if block.so statement in if block should also give exception as this one do, but its not doing so.why? ***response.sendRedirect("http://localhost:8625/ServletPrc/login% 20page.html"); if(true) { //same statement as above ***response.sendRedirect("http://localhost:8625/ServletPrc/login%20page.html"); } else{ request.setAttribute("noOfReq", noOfRequests); request.setAttribute("name", new Name().getName()); request.setAttribute("GmailId",this.getServletConfig().getInitParameter("GmailId") ); request.setAttribute("YahooId",this.getServletConfig().getInitParameter("YahooId") ); RequestDispatcher view1=request.getRequestDispatcher("HomePage.jsp"); view1.forward(request, response); } }

    Read the article

  • Starting synergy automatically on RHEL/CentOS

    - by Matt
    I have a Red Had Enterprise Linux 5 and a CentOS 5 box, both of which I am trying to configure to automatically connect to a synergy server on startup. I have followed the guide at http://synergy2.sourceforge.net/autostart.html and configured them the same way I configured previous Ubuntu 7.10 boxes, and this only seems to get me half way there. Currently, synergy connects at the login screen, but once I login, it doesn't come back up. I added the following lines to /etc/gdm/{Init,PostLogin,PreSession}/Default : /usr/bin/killall synergyc sleep 1 /usr/bin/synergyc fried-chicken # Init,PreSession only All files are owned by root:root with 755 permissions, I'm just not sure what I'm missing here.

    Read the article

  • Are there any programming languages targeting PHP, besides haXe?

    - by stesch
    PHP doesn't get much love but is still a winner at easy deployment (for cheap hosting). Are there any programming languages (besides haXe) that target PHP? Writing applications in this language and then translating it into PHP, like some languages target C as an intermediate language? The Scheme implementation Chicken compiles into C. XOTcl converts Java code into Tcl code LINJ was(?) a tool to convert Lisp into nice looking Java code … + a lot of ways to produce JavaScript without touching JavaScript.

    Read the article

  • What comes first in Ruby's object model?

    - by Timothy
    I've been reading Metaprogramming Ruby and the object model like the chicken or egg dilemma. In Ruby 1.8, the Object class is an instance of Class. Module's superclass is Object and is an instance of Class. Class' superclass is Module, and it is an instance of Class (self-referential). Say class SomeClass; end is defined somewhere; SomeClass is an instance of Class, however its superclass is Object. Why does an instance of Class have Object as the superclass instead of nil? Also, if Object is to exist, then Class has to exist, but then Module has to exist, but for Module to exist Object has to exist. How are these classes created?

    Read the article

  • jquery :not selector not working in next() method

    - by Richard
    what is the next best thing to use when you want to select the next li item, but not the one that has someClassName. The not selector returns an empty array! or is this a case off using filter? <li class="first">pickle</> <li class="someClassName">tomato</li> <li>chicken</> <li>cocosnut</> var current = $('ul.items li.first'); var next = current.next(':not(li.someClassName)'); thanks, Richard

    Read the article

  • JSF skips phases - How to debug that?

    - by Pentius
    Hey fellows, I have to debug a foreign jsf application thanks god. The problem is, that I submit a form, but the values aren't carried over. With a phase listener I can see, that the life cycle doesn't run completely through, so to say it skips phase 2 -5: After the restore view phase, the render response phase is directly called. I miss the apply values, validation, update model actions and so on. So, this could be a chicken-and-egg problem: 1. The responsible phases aren't called, so the new form input can't be carried over. 2. The system doesn't recognize any new input and therefore directly renders after restoring the view. I checked that there is no call of responseComplete() oder renderResponse(). I'm stuck somehow. Any idea to validate one of the two hypothesis? Or how to debug that in general? Did anybody have a similar problem?

    Read the article

  • In which year was the date the same as the original year?

    - by Marta
    It's my first question on this site, but I always found this site really useful. What I mean with my question is: you ask the person to give a date (eg. Fill in a date [dd-mm-yyyy]: 16-10-2013) you than have to ask an interval between 2 years (eg. Give an interval [yyyy-yyyy]:1800-2000) When the program runs, it has to show what day of the week the given date is. In this case it was a Wednesday. Than the program has to look in which year, in between the interval, the date 16 October also fell on a Wednesday. So in the end it has to look something like this: Fill in a date: [dd-mm-yyyy]: 16-10-2013 Give an interval [yyyy-yyyy]: 1900-2000 16 October was a wednesday in the following years: 1905 1911 1916 1922 1933 1939 1944 1950 1961 1967 1972 1978 1989 1995 2000 The full date is Wednesday 16 October, 2013 The small (or biggest) problem is, I am not allowed to use the DATE.function in java. If someone can help me with the second part I would be really really happy, cause I have no idea how I am supposed to do this To find out what day of the week the given date falls, I use the Zeller Congruence class Day { Date date; //To grab the month and year form the Date class int day; final static String[] DAYS_OF_WEEK = { "Saturday", "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday" }; public void dayWeekInterval{ //code to grab the interval from interval Class, and doing stuff here } public void dayOfTheWeek { int m = date.getMonth(); int y = date.getYear(); if (m < 3) { m += 12; y -= 1; } int k = y % 100; int j = y / 100; int day = ((q + (((m + 1) * 26) / 10) + k + (k / 4) + (j / 4)) + (5 * j)) % 7; return day; } public string ToString(){ return "" + DAYS_OF_WEEK[day] + day; } }

    Read the article

  • how to get contents of site use HTTPS

    - by cashmoney
    ex of site using ssl ( HTTPs ) : https://www.eb2a.com 1 - i tried to get its content using file_get_contents, but not work and give error ex : <?php $contents = file_get_contents("https://www.eb2a.com/"); echo $contents; ?> 2 - i tried to use fopen, but not work and give error ex: <?php $url = 'https://www.eb2a.com/'; $contents = fopen($url, 'r'); echo "$contents"; ?> 3 - i tried to use CURL, but not work and give BLANK PAGE ex : function cURL($url, $ref, $header, $cookie, $p){ $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, $url); curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0); curl_setopt($ch, CURLOPT_USERAGENT, $_SERVER['HTTP_USER_AGENT']); curl_setopt($ch, CURLOPT_REFERER, $ref); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0); if ($p) { curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST"); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, $p); } $result = curl_exec($ch); curl_close($ch); if ($result){ return $result; }else{ return ''; } } $file = cURL('https://www.eb2a.com/','https://www.eb2a.com/',0,0,null); echo $file any one have any idea ??

    Read the article

  • Automating Firefox configuration settings

    - by Richard100
    Hi All, During web development work, I need to be able to quickly switch various config settings in Firefox. In particular I need to be able to: 1) Switch off cookies 2) Switch off javascript 3) Switch my user agent (I have the user-agent switcher add-on installed) and then back again. Instead of doing this manually, it would be great if i could add a "macro" button to my toolbar that I could simply click to toggle the three settings above. Anyone know if this is possible? Btw - Firefox Profiles doesn't really cut it. You can't dynamically switch profiles within a specific Firefox instance, which I need to be able to do. Btw2 - I got excited when i saw Greasemonkey, Chicken Foot, but it looks like these can only automate browsing/DOM tasks, and not with firefox configuration settings. Thanks Richard.

    Read the article

  • Dropdown binding and postbacks - ASP.NET

    - by DotnetDude
    I have a rather complex page. The ASPX page loads a user control which in turn loads a child User control. Parent Control protected override void OnInit(EventArgs e) { //Loads child control } In the child user control, I use custom control that inherits from System.Web.UI.HtmlControls.HtmlSelect ASCX: <cust:CustDropDownList id="ctlDdl" runat="server"/> ASCX.CS protected void Page_Load(object sender, EventArgs e) { //Binds CtlDdl here } When the user clicks on the Save button, the controls get user controls get dynamically reloaded, but Iose the value the user has selected in the dropdown. I run into the chicken and egg problem here. I think I need to bind the ctlDdl only on if its not a postback, but that results in the dropdown not getting populated. If I bind it everytime, then i lose user's selection EDIT: Can someone respond to my comment to Jonathan's answer? Thanks

    Read the article

  • How to handle recursive parent/child problems like this?

    - by lsdude
    In web dev I come across these problems a lot. For example, we have a giant list of URLs that are in this format: /businesses /businesses/food /businesses/food/wendys /businesses/food/wendys/chili /businesses/food/wendys/fries /businesses/food/wendys/chicken-nuggets /businesses/pharmacy/cvs /businesses/pharmacy/cvs/toothpaste /businesses/pharmacy/cvs/toothpaste/brand ... and then we need to output each one, where the parent category is in h1 tags, the child is in h2 tags, and the children of that are in h3 tags. I can handle this but I feel my code is messy. I'm sure there is a design pattern I can use? Langs are ruby/php usually. how would you handle this?

    Read the article

  • Searching and comparing ActiveRecord attributes to find largest value

    - by NS
    I have a model that would look something like: my_diet = Diet.new my_diet.food_type_1 = "beef" my_diet.food_type_1_percentage = 40 my_diet.food_type_2 = "carrots" my_diet.food_type_2_percentage = 50 my_diet.food_type_3 = "beans" my_diet.food_type_3_percentage = 5 my_diet.food_type_4 = "chicken" my_diet.food_type_4_percentage = 5 I need to find which food_type has the highest percentage. So far I've tried creating a hash out of the attibutes and percentages then sorting the hash (see below) but it feels like there must be a cleaner way to do it. food_type_percentages = { :food_type_1 => my_diet.foo_type_percentage_1_percentage.nil? ? 0 : my_dient.food_type_1_percentage, :food_type_2 => my_diet.foo_type_percentage_2_percentage.nil? ? 0 : my_dient.food_type_2_percentage, :food_type_3 => my_diet.foo_type_percentage_3_percentage.nil? ? 0 : my_dient.food_type_3_percentage, :food_type_4 => my_diet.foo_type_percentage_4_percentage.nil? ? 0 : my_dient.food_type_4_percentage } food_type_percentages.sort {|a,b| a[1]<=>b[1]}.last Any ideas? Thanks!

    Read the article

  • Memcached getDelayed alternative implementation

    - by iBobo
    I would like to use getDelayed on the PHP Memcached extension but I think it's not implemented in the right way. Right now you ask for some keys and then retrieve all of them with fetch() and fetchAll(). But imagine a scenario where I need to retrieve 15 keys used in different parts of the page which I don't know in advance, but I can ask the various objects to give me the list. What I want is give the Memcached instance this list (each component would give its part) then later when I need them retrieve from the instance, but not all of them at once: each component would take the one it needs. Basically if I were to implement this I would prohibit using getDelayed alone and implement a bookGet($keys) method where you would add the keys to book (which actually calls getDelayed), and redefine get to handle these three cases: key is booked and retrieved - return the value; key is booked but not retrieved - go and force the fetch of the booked keys and return the correct value; key not booked - do a normal lookup. I want to know if this makes sense, your thoughts on the subject and if someone already implemented this or maybe PECL Memcached already works this way and actually the documentation doesn't explain it correctly.

    Read the article

  • Website badge system

    - by linkyndy
    I am currently working on a widget-based website, built entirely on user socialization. Since a reputation system pays off for attracting users, I decided to implement one of these. Now, I would like to hear some solutions on how should this be implemented the right way (take, for example, Foursquare's badge system). Basically, I need to be able to do the following: have a badges table, where I can add, edit and delete badges; be able to enable and disable a badge; be able to introduce a new badge, but without writing new code - simply give some parameters to the add badge form regarding what should be followed in order for a user to receive a badge; be able to give badges in real time - meaning that whenever a user accomplishes whatever it needs to receive a badge, the system should know immediately to give the badge to that user; also, the system should not be overloaded with "badge listeners" - I believe interrogating each user request with every badge requirements is time consuming; These being said, I would like to hear your opinions on how to implement the right way a badge system (logic, database schema, methods etc.) Thank you very much!

    Read the article

  • License For (Mostly) Open Source Website / Service

    - by Ryan Sullivan
    I have an interesting setup and am not sure how to license a website. I know this is not legal advice, and I am not asking for any. There are so many different Open Source Licenses and I do not have the time to read every last one to see which best fits my situation. Really, I am looking for suggestions and a nudge in the right direction. My setup is: I give away for free version of my web service with a clean website interface. The implementation I use in the actual web site is (almost) identical to what I give away. The main service works the exactly the same way, but the website interface to manage features in the service is fairly different. Really the web interfaces have the same exact backend, and the front ends accomplish the same tasks, but the service I offer on my site is very rich and uses a good deal of javascript, where I kept the interface in the version I give away as simple and javascript-less as possible. Mostly so it is easy to understand and integrate into other sites. I am not entirely sure how I should license this. It is more like I develop an open source service but have a separate site built upon it. I like the GPLv3 but I am not sure if I can use it in this case especially since I am making some money off of google ad's on the site and plan on using amazon affiliates as well. Any help would be greatly appreciated. I do want to open it up as much as possible. But I still want to be able to continue with my own implementation. Thanks in advance for any information or help anyone can provide.

    Read the article

  • Memcached: booking a fetch

    - by iBobo
    I would like to use getDelayed on the PHP Memcached extension but I think it's not implemented in the right way. Right now you ask for some keys and then retrieve all of them with fetch() and fetchAll(). But imagine a scenario where I need to retrieve 15 keys used in different parts of the page which I don't know in advance, but I can ask the various objects to give me the list. What I want is give the Memcached instance this list (each component would give its part) then later when I need them retrieve from the instance, but not all of them at once: each component would take the one it needs. Basically if I were to implement this I would prohibit using getDelayed alone and implement a bookGet($keys) method where you would add the keys to book (which actually calls getDelayed), and redefine get to handle these three cases: key is booked and retrieved - return the value; key is booked but not retrieved - go and force the fetch of the booked keys and return the correct value; key not booked - do a normal lookup. I want to know if this makes sense, your thoughts on the subject and if someone already implemented this or maybe PECL Memcached already works this way and actually the documentation doesn't explain it correctly.

    Read the article

  • C#/.NET Little Wonders: The Generic Func Delegates

    - by James Michael Hare
    Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Back in one of my three original “Little Wonders” Trilogy of posts, I had listed generic delegates as one of the Little Wonders of .NET.  Later, someone posted a comment saying said that they would love more detail on the generic delegates and their uses, since my original entry just scratched the surface of them. Last week, I began our look at some of the handy generic delegates built into .NET with a description of delegates in general, and the Action family of delegates.  For this week, I’ll launch into a look at the Func family of generic delegates and how they can be used to support generic, reusable algorithms and classes. Quick Delegate Recap Delegates are similar to function pointers in C++ in that they allow you to store a reference to a method.  They can store references to either static or instance methods, and can actually be used to chain several methods together in one delegate. Delegates are very type-safe and can be satisfied with any standard method, anonymous method, or a lambda expression.  They can also be null as well (refers to no method), so care should be taken to make sure that the delegate is not null before you invoke it. Delegates are defined using the keyword delegate, where the delegate’s type name is placed where you would typically place the method name: 1: // This delegate matches any method that takes string, returns nothing 2: public delegate void Log(string message); This delegate defines a delegate type named Log that can be used to store references to any method(s) that satisfies its signature (whether instance, static, lambda expression, etc.). Delegate instances then can be assigned zero (null) or more methods using the operator = which replaces the existing delegate chain, or by using the operator += which adds a method to the end of a delegate chain: 1: // creates a delegate instance named currentLogger defaulted to Console.WriteLine (static method) 2: Log currentLogger = Console.Out.WriteLine; 3:  4: // invokes the delegate, which writes to the console out 5: currentLogger("Hi Standard Out!"); 6:  7: // append a delegate to Console.Error.WriteLine to go to std error 8: currentLogger += Console.Error.WriteLine; 9:  10: // invokes the delegate chain and writes message to std out and std err 11: currentLogger("Hi Standard Out and Error!"); While delegates give us a lot of power, it can be cumbersome to re-create fairly standard delegate definitions repeatedly, for this purpose the generic delegates were introduced in various stages in .NET.  These support various method types with particular signatures. Note: a caveat with generic delegates is that while they can support multiple parameters, they do not match methods that contains ref or out parameters. If you want to a delegate to represent methods that takes ref or out parameters, you will need to create a custom delegate. We’ve got the Func… delegates Just like it’s cousin, the Action delegate family, the Func delegate family gives us a lot of power to use generic delegates to make classes and algorithms more generic.  Using them keeps us from having to define a new delegate type when need to make a class or algorithm generic. Remember that the point of the Action delegate family was to be able to perform an “action” on an item, with no return results.  Thus Action delegates can be used to represent most methods that take 0 to 16 arguments but return void.  You can assign a method The Func delegate family was introduced in .NET 3.5 with the advent of LINQ, and gives us the power to define a function that can be called on 0 to 16 arguments and returns a result.  Thus, the main difference between Action and Func, from a delegate perspective, is that Actions return nothing, but Funcs return a result. The Func family of delegates have signatures as follows: Func<TResult> – matches a method that takes no arguments, and returns value of type TResult. Func<T, TResult> – matches a method that takes an argument of type T, and returns value of type TResult. Func<T1, T2, TResult> – matches a method that takes arguments of type T1 and T2, and returns value of type TResult. Func<T1, T2, …, TResult> – and so on up to 16 arguments, and returns value of type TResult. These are handy because they quickly allow you to be able to specify that a method or class you design will perform a function to produce a result as long as the method you specify meets the signature. For example, let’s say you were designing a generic aggregator, and you wanted to allow the user to define how the values will be aggregated into the result (i.e. Sum, Min, Max, etc…).  To do this, we would ask the user of our class to pass in a method that would take the current total, the next value, and produce a new total.  A class like this could look like: 1: public sealed class Aggregator<TValue, TResult> 2: { 3: // holds method that takes previous result, combines with next value, creates new result 4: private Func<TResult, TValue, TResult> _aggregationMethod; 5:  6: // gets or sets the current result of aggregation 7: public TResult Result { get; private set; } 8:  9: // construct the aggregator given the method to use to aggregate values 10: public Aggregator(Func<TResult, TValue, TResult> aggregationMethod = null) 11: { 12: if (aggregationMethod == null) throw new ArgumentNullException("aggregationMethod"); 13:  14: _aggregationMethod = aggregationMethod; 15: } 16:  17: // method to add next value 18: public void Aggregate(TValue nextValue) 19: { 20: // performs the aggregation method function on the current result and next and sets to current result 21: Result = _aggregationMethod(Result, nextValue); 22: } 23: } Of course, LINQ already has an Aggregate extension method, but that works on a sequence of IEnumerable<T>, whereas this is designed to work more with aggregating single results over time (such as keeping track of a max response time for a service). We could then use this generic aggregator to find the sum of a series of values over time, or the max of a series of values over time (among other things): 1: // creates an aggregator that adds the next to the total to sum the values 2: var sumAggregator = new Aggregator<int, int>((total, next) => total + next); 3:  4: // creates an aggregator (using static method) that returns the max of previous result and next 5: var maxAggregator = new Aggregator<int, int>(Math.Max); So, if we were timing the response time of a web method every time it was called, we could pass that response time to both of these aggregators to get an idea of the total time spent in that web method, and the max time spent in any one call to the web method: 1: // total will be 13 and max 13 2: int responseTime = 13; 3: sumAggregator.Aggregate(responseTime); 4: maxAggregator.Aggregate(responseTime); 5:  6: // total will be 20 and max still 13 7: responseTime = 7; 8: sumAggregator.Aggregate(responseTime); 9: maxAggregator.Aggregate(responseTime); 10:  11: // total will be 40 and max now 20 12: responseTime = 20; 13: sumAggregator.Aggregate(responseTime); 14: maxAggregator.Aggregate(responseTime); The Func delegate family is useful for making generic algorithms and classes, and in particular allows the caller of the method or user of the class to specify a function to be performed in order to generate a result. What is the result of a Func delegate chain? If you remember, we said earlier that you can assign multiple methods to a delegate by using the += operator to chain them.  So how does this affect delegates such as Func that return a value, when applied to something like the code below? 1: Func<int, int, int> combo = null; 2:  3: // What if we wanted to aggregate the sum and max together? 4: combo += (total, next) => total + next; 5: combo += Math.Max; 6:  7: // what is the result? 8: var comboAggregator = new Aggregator<int, int>(combo); Well, in .NET if you chain multiple methods in a delegate, they will all get invoked, but the result of the delegate is the result of the last method invoked in the chain.  Thus, this aggregator would always result in the Math.Max() result.  The other chained method (the sum) gets executed first, but it’s result is thrown away: 1: // result is 13 2: int responseTime = 13; 3: comboAggregator.Aggregate(responseTime); 4:  5: // result is still 13 6: responseTime = 7; 7: comboAggregator.Aggregate(responseTime); 8:  9: // result is now 20 10: responseTime = 20; 11: comboAggregator.Aggregate(responseTime); So remember, you can chain multiple Func (or other delegates that return values) together, but if you do so you will only get the last executed result. Func delegates and co-variance/contra-variance in .NET 4.0 Just like the Action delegate, as of .NET 4.0, the Func delegate family is contra-variant on its arguments.  In addition, it is co-variant on its return type.  To support this, in .NET 4.0 the signatures of the Func delegates changed to: Func<out TResult> – matches a method that takes no arguments, and returns value of type TResult (or a more derived type). Func<in T, out TResult> – matches a method that takes an argument of type T (or a less derived type), and returns value of type TResult(or a more derived type). Func<in T1, in T2, out TResult> – matches a method that takes arguments of type T1 and T2 (or less derived types), and returns value of type TResult (or a more derived type). Func<in T1, in T2, …, out TResult> – and so on up to 16 arguments, and returns value of type TResult (or a more derived type). Notice the addition of the in and out keywords before each of the generic type placeholders.  As we saw last week, the in keyword is used to specify that a generic type can be contra-variant -- it can match the given type or a type that is less derived.  However, the out keyword, is used to specify that a generic type can be co-variant -- it can match the given type or a type that is more derived. On contra-variance, if you are saying you need an function that will accept a string, you can just as easily give it an function that accepts an object.  In other words, if you say “give me an function that will process dogs”, I could pass you a method that will process any animal, because all dogs are animals.  On the co-variance side, if you are saying you need a function that returns an object, you can just as easily pass it a function that returns a string because any string returned from the given method can be accepted by a delegate expecting an object result, since string is more derived.  Once again, in other words, if you say “give me a method that creates an animal”, I can pass you a method that will create a dog, because all dogs are animals. It really all makes sense, you can pass a more specific thing to a less specific parameter, and you can return a more specific thing as a less specific result.  In other words, pay attention to the direction the item travels (parameters go in, results come out).  Keeping that in mind, you can always pass more specific things in and return more specific things out. For example, in the code below, we have a method that takes a Func<object> to generate an object, but we can pass it a Func<string> because the return type of object can obviously accept a return value of string as well: 1: // since Func<object> is co-variant, this will access Func<string>, etc... 2: public static string Sequence(int count, Func<object> generator) 3: { 4: var builder = new StringBuilder(); 5:  6: for (int i=0; i<count; i++) 7: { 8: object value = generator(); 9: builder.Append(value); 10: } 11:  12: return builder.ToString(); 13: } Even though the method above takes a Func<object>, we can pass a Func<string> because the TResult type placeholder is co-variant and accepts types that are more derived as well: 1: // delegate that's typed to return string. 2: Func<string> stringGenerator = () => DateTime.Now.ToString(); 3:  4: // This will work in .NET 4.0, but not in previous versions 5: Sequence(100, stringGenerator); Previous versions of .NET implemented some forms of co-variance and contra-variance before, but .NET 4.0 goes one step further and allows you to pass or assign an Func<A, BResult> to a Func<Y, ZResult> as long as A is less derived (or same) as Y, and BResult is more derived (or same) as ZResult. Sidebar: The Func and the Predicate A method that takes one argument and returns a bool is generally thought of as a predicate.  Predicates are used to examine an item and determine whether that item satisfies a particular condition.  Predicates are typically unary, but you may also have binary and other predicates as well. Predicates are often used to filter results, such as in the LINQ Where() extension method: 1: var numbers = new[] { 1, 2, 4, 13, 8, 10, 27 }; 2:  3: // call Where() using a predicate which determines if the number is even 4: var evens = numbers.Where(num => num % 2 == 0); As of .NET 3.5, predicates are typically represented as Func<T, bool> where T is the type of the item to examine.  Previous to .NET 3.5, there was a Predicate<T> type that tended to be used (which we’ll discuss next week) and is still supported, but most developers recommend using Func<T, bool> now, as it prevents confusion with overloads that accept unary predicates and binary predicates, etc.: 1: // this seems more confusing as an overload set, because of Predicate vs Func 2: public static SomeMethod(Predicate<int> unaryPredicate) { } 3: public static SomeMethod(Func<int, int, bool> binaryPredicate) { } 4:  5: // this seems more consistent as an overload set, since just uses Func 6: public static SomeMethod(Func<int, bool> unaryPredicate) { } 7: public static SomeMethod(Func<int, int, bool> binaryPredicate) { } Also, even though Predicate<T> and Func<T, bool> match the same signatures, they are separate types!  Thus you cannot assign a Predicate<T> instance to a Func<T, bool> instance and vice versa: 1: // the same method, lambda expression, etc can be assigned to both 2: Predicate<int> isEven = i => (i % 2) == 0; 3: Func<int, bool> alsoIsEven = i => (i % 2) == 0; 4:  5: // but the delegate instances cannot be directly assigned, strongly typed! 6: // ERROR: cannot convert type... 7: isEven = alsoIsEven; 8:  9: // however, you can assign by wrapping in a new instance: 10: isEven = new Predicate<int>(alsoIsEven); 11: alsoIsEven = new Func<int, bool>(isEven); So, the general advice that seems to come from most developers is that Predicate<T> is still supported, but we should use Func<T, bool> for consistency in .NET 3.5 and above. Sidebar: Func as a Generator for Unit Testing One area of difficulty in unit testing can be unit testing code that is based on time of day.  We’d still want to unit test our code to make sure the logic is accurate, but we don’t want the results of our unit tests to be dependent on the time they are run. One way (of many) around this is to create an internal generator that will produce the “current” time of day.  This would default to returning result from DateTime.Now (or some other method), but we could inject specific times for our unit testing.  Generators are typically methods that return (generate) a value for use in a class/method. For example, say we are creating a CacheItem<T> class that represents an item in the cache, and we want to make sure the item shows as expired if the age is more than 30 seconds.  Such a class could look like: 1: // responsible for maintaining an item of type T in the cache 2: public sealed class CacheItem<T> 3: { 4: // helper method that returns the current time 5: private static Func<DateTime> _timeGenerator = () => DateTime.Now; 6:  7: // allows internal access to the time generator 8: internal static Func<DateTime> TimeGenerator 9: { 10: get { return _timeGenerator; } 11: set { _timeGenerator = value; } 12: } 13:  14: // time the item was cached 15: public DateTime CachedTime { get; private set; } 16:  17: // the item cached 18: public T Value { get; private set; } 19:  20: // item is expired if older than 30 seconds 21: public bool IsExpired 22: { 23: get { return _timeGenerator() - CachedTime > TimeSpan.FromSeconds(30.0); } 24: } 25:  26: // creates the new cached item, setting cached time to "current" time 27: public CacheItem(T value) 28: { 29: Value = value; 30: CachedTime = _timeGenerator(); 31: } 32: } Then, we can use this construct to unit test our CacheItem<T> without any time dependencies: 1: var baseTime = DateTime.Now; 2:  3: // start with current time stored above (so doesn't drift) 4: CacheItem<int>.TimeGenerator = () => baseTime; 5:  6: var target = new CacheItem<int>(13); 7:  8: // now add 15 seconds, should still be non-expired 9: CacheItem<int>.TimeGenerator = () => baseTime.AddSeconds(15); 10:  11: Assert.IsFalse(target.IsExpired); 12:  13: // now add 31 seconds, should now be expired 14: CacheItem<int>.TimeGenerator = () => baseTime.AddSeconds(31); 15:  16: Assert.IsTrue(target.IsExpired); Now we can unit test for 1 second before, 1 second after, 1 millisecond before, 1 day after, etc.  Func delegates can be a handy tool for this type of value generation to support more testable code.  Summary Generic delegates give us a lot of power to make truly generic algorithms and classes.  The Func family of delegates is a great way to be able to specify functions to calculate a result based on 0-16 arguments.  Stay tuned in the weeks that follow for other generic delegates in the .NET Framework!   Tweet Technorati Tags: .NET, C#, CSharp, Little Wonders, Generics, Func, Delegates

    Read the article

  • 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!

    Read the article

  • Unable to execute file in the temporary directory

    - by Bixal
    I am using Windows 8.1 Pro 64-bit. I see this error, almost everytime I launch an executable file (to install it) but not for all of them. I don't see the error when I use Run as Administrator. I looked around, and found a solution: I needed to give permissions to the current user for the temp file as shown in the picture below: The problem here is solved temporarily, but it goes back to give me the same problem after restarting the PC. What can I do to prevent such a thing? I don't really want to use the built in Administrator account all the time. Update: The problem is caused by the cracked version of Adobe Acrobat. And the root cause is the cracked amtlib.dll Read more here: http://www.sabernova.com/2013/12/cracked-adobe-acrobat-xi-will-revert.html#axzz2r8VSzZi9

    Read the article

  • Create and Consume WCF service using Visual Studio 2010

    - by sreejukg
    In this article I am going to demonstrate how to create a WCF service, that can be hosted inside IIS and a windows application that consume the WCF service. To support service oriented architecture, Microsoft developed the programming model named Windows Communication Foundation (WCF). ASMX was the prior version from Microsoft, was completely based on XML and .Net framework continues to support ASMX web services in future versions also. While ASMX web services was the first step towards the service oriented architecture, Microsoft has made a big step forward by introducing WCF. An overview of planning for WCF can be found from this link http://msdn.microsoft.com/en-us/library/ff649584.aspx . The following are the important differences between WCF and ASMX from an asp.net developer point of view. 1. ASMX web services are easy to write, configure and consume 2. ASMX web services are only hosted in IIS 3. ASMX web services can only use http 4. WCF, can be hosted inside IIS, windows service, console application, WAS(Windows Process Activation Service) etc 5. WCF can be used with HTTP, TCP/IP, MSMQ and other protocols. The detailed difference between ASMX web service and WCF can be found here. http://msdn.microsoft.com/en-us/library/cc304771.aspx Though WCF is a bigger step for future, Visual Studio makes it simpler to create, publish and consume the WCF service. In this demonstration, I am going to create a service named SayHello that accepts 2 parameters such as name and language code. The service will return a hello to user name that corresponds to the language. So the proposed service usage is as follows. Caller: SayHello(“Sreeju”, “en”) -> return value -> Hello Sreeju Caller: SayHello(“???”, “ar”) -> return value -> ????? ??? Caller: SayHello(“Sreeju”, “es”) - > return value -> Hola Sreeju Note: calling an automated translation service is not the intention of this article. If you are interested, you can find bing translator API and can use in your application. http://www.microsofttranslator.com/dev/ So Let us start First I am going to create a Service Application that offer the SayHello Service. Open Visual Studio 2010, Go to File -> New Project, from your preferred language from the templates section select WCF, select WCF service application as the project type, give the project a name(I named it as HelloService), click ok so that visual studio will create the project for you. In this demonstration, I have used C# as the programming language. Visual studio will create the necessary files for you to start with. By default it will create a service with name Service1.svc and there will be an interface named IService.cs. The screenshot for the project in solution explorer is as follows Since I want to demonstrate how to create new service, I deleted Service1.Svc and IService1.cs files from the project by right click the file and select delete. Now in the project there is no service available, I am going to create one. From the solution explorer, right click the project, select Add -> New Item Add new item dialog will appear to you. Select WCF service from the list, give the name as HelloService.svc, and click on the Add button. Now Visual studio will create 2 files with name IHelloService.cs and HelloService.svc. These files are basically the service definition (IHelloService.cs) and the service implementation (HelloService.svc). Let us examine the IHelloService interface. The code state that IHelloService is the service definition and it provides an operation/method (similar to web method in ASMX web services) named DoWork(). Any WCF service will have a definition file as an Interface that defines the service. Let us see what is inside HelloService.svc The code illustrated is implementing the interface IHelloService. The code is self-explanatory; the HelloService class needs to implement all the methods defined in the Service Definition. Let me do the service as I require. Open IHelloService.cs in visual studio, and delete the DoWork() method and add a definition for SayHello(), do not forget to add OperationContract attribute to the method. The modified IHelloService.cs will look as follows Now implement the SayHello method in the HelloService.svc.cs file. Here I wrote the code for SayHello method as follows. I am done with the service. Now you can build and run the service by clicking f5 (or selecting start debugging from the debug menu). Visual studio will host the service in give you a client to test it. The screenshot is as follows. In the left pane, it shows the services available in the server and in right side you can invoke the service. To test the service sayHello, double click on it from the above window. It will ask you to enter the parameters and click on the invoke button. See a sample output below. Now I have done with the service. The next step is to write a service client. Creating a consumer application involves 2 steps. One generating the class and configuration file corresponds to the service. Create a project that utilizes the generated class and configuration file. First I am going to generate the class and configuration file. There is a great tool available with Visual Studio named svcutil.exe, this tool will create the necessary class and configuration files for you. Read the documentation for the svcutil.exe here http://msdn.microsoft.com/en-us/library/aa347733.aspx . Open Visual studio command prompt, you can find it under Start Menu -> All Programs -> Visual Studio 2010 -> Visual Studio Tools -> Visual Studio command prompt Make sure the service is in running state in visual studio. Note the url for the service(from the running window, you can right click and choose copy address). Now from the command prompt, enter the svcutil.exe command as follows. I have mentioned the url and the /d switch – for the directory to store the output files(In this case d:\temp). If you are using windows drive(in my case it is c: ) , make sure you open the command prompt with run as administrator option, otherwise you will get permission error(Only in windows 7 or windows vista). The tool has created 2 files, HelloService.cs and output.config. Now the next step is to create a new project and use the created files and consume the service. Let us do that now. I am going to add a console application to the current solution. Right click solution name in the solution explorer, right click, Add-> New Project Under Visual C#, select console application, give the project a name, I named it TestService Now navigate to d:\temp where I generated the files with the svcutil.exe. Rename output.config to app.config. Next step is to add both files (d:\temp\helloservice.cs and app.config) to the files. In the solution explorer, right click the project, Add -> Add existing item, browse to the d:\temp folder, select the 2 files as mentioned before, click on the add button. Now you need to add a reference to the System.ServiceModel to the project. From solution explorer, right click the references under testservice project, select Add reference. In the Add reference dialog, select the .Net tab, select System.ServiceModel, and click ok Now open program.cs by double clicking on it and add the code to consume the web service to the main method. The modified file looks as follows Right click the testservice project and set as startup project. Click f5 to run the project. See the sample output as follows Publishing WCF service under IIS is similar to publishing ASP.Net application. Publish the application to a folder using Visual studio publishing feature, create a virtual directory and create it as an application. Don’t forget to set the application pool to use ASP.Net version 4. One last thing you need to check is the app.config file you have added to the solution. See the element client under ServiceModel element. There is an endpoint element with address attribute that points to the published service URL. If you permanently host the service under IIS, you can simply change the address parameter to the corresponding one and your application will consume the service. You have seen how easily you can build/consume WCF service. If you need the solution in zipped format, please post your email below.

    Read the article

< Previous Page | 36 37 38 39 40 41 42 43 44 45 46 47  | Next Page >