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• Mutable Records in F#

  - by MarkPearl

  I’m loving my expert F# book – today I thought I would give a post on using mutable records as covered in Chapter 4 of Expert F#. So as they explain the simplest mutable data structures in F# are mutable records. The whole concept of things by default being immutable is a new one for me from my C# background. Anyhow… lets look at some C# code first. using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace MutableRecords { public class DiscreteEventCounter { public int Total { get; set; } public int Positive { get; set; } public string Name { get; private set; } public DiscreteEventCounter(string name) { Name = name; } } class Program { private static void recordEvent(DiscreteEventCounter s, bool isPositive) { s.Total += 1; if (isPositive) s.Positive += 1; } private static void reportStatus (DiscreteEventCounter s) { Console.WriteLine("We have {0} {1} out of {2}", s.Positive, s.Name, s.Total); } static void Main(string[] args) { var longCounter = new DiscreteEventCounter("My Discrete Counter"); recordEvent(longCounter, true); recordEvent(longCounter, true); reportStatus(longCounter); Console.ReadLine(); } } } Quite simple, we have a class that has a few values. We instantiate an instance of the class and perform increments etc on the instance. Now lets look at an equivalent F# sample. namespace EncapsulationNS module Module1 = open System type DiscreteEventCounter = { mutable Total : int mutable Positive : int Name : string } let recordEvent (s: DiscreteEventCounter) isPositive = s.Total <- s.Total+1 if isPositive then s.Positive <- s.Positive+1 let reportStatus (s: DiscreteEventCounter) = printfn "We have %d %s out of %d" s.Positive s.Name s.Total let newCounter nm = { Total = 0; Positive = 0; Name = nm } // // Using it... // let longCounter = newCounter "My Discrete Counter" recordEvent longCounter (true) recordEvent longCounter (true) reportStatus longCounter System.Console.ReadLine() Notice in the type declaration of the DiscreteEventCounter we had to explicitly declare that the total and positive value holders were mutable. And that’s it – a very simple example of mutable types.

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• Problem animating in Unity/Orthello 2D. Can't move gameObject

  - by Nelson Gregório

  I have a enemy npc that moves left and right in a corridor. It's animated with 2 sprites using Orthello 2D Framework. If I untick the animation's play on start and looping, the npc moves correctly. If I turn it on, the npc tries to move but is pulled back to his starting position again and again because of the animation loop. If I turn looping off during runtime, the npc moves correctly again. What did I do wrong? Here's the npc code if needed. using UnityEngine; using System.Collections; public class Enemies : MonoBehaviour { private Vector2 movement; public float moveSpeed = 200; public bool started = true; public bool blockedRight = false; public bool blockedLeft = false; public GameObject BorderL; public GameObject BorderR; void Update () { if (gameObject.transform.position.x < BorderL.transform.position.x) { started = false; blockedRight = false; blockedLeft = true; } if (gameObject.transform.position.x > BorderR.transform.position.x) { started = false; blockedLeft = false; blockedRight = true; } if(started) { movement = new Vector2(1, 0f); movement *= Time.deltaTime*moveSpeed; gameObject.transform.Translate(movement.x,movement.y, 0f); } if(!blockedRight && !started && blockedLeft) { movement = new Vector2(1, 0f); movement *= Time.deltaTime*moveSpeed; gameObject.transform.Translate(movement.x,movement.y, 0f); } if(!blockedLeft && !started && blockedRight) { movement = new Vector2(-1, 0f); movement *= Time.deltaTime*moveSpeed; gameObject.transform.Translate(movement.x,movement.y, 0f); } } }

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• Java word scramble game [closed]

  - by Dan

  I'm working on code for a word scramble game in Java. I know the code itself is full of bugs right now, but my main focus is getting a vector of strings broken into two separate vectors containing hints and words. The text file that the strings are taken from has a colon separating them. So here is what I have so far. public WordApp() { inputRow = new TextInputBox(); inputRow.setLocation(200,100); phrases = new Vector <String>(FileUtilities.getStrings()); v_hints = new Vector<String>(); v_words = new Vector<String>(); textBox = new TextBox(200,100); textBox.setLocation(200,200); textBox.setText(scrambled + "\n\n Time Left: \t" + seconds/10 + "\n Score: \t" + score); hintBox = new TextBox(200,200); hintBox.setLocation(300,400); hintBox.hide(); Iterator <String> categorize = phrases.iterator(); while(categorize.hasNext()) { int index = phrases.indexOf(":"); String element = categorize.next(); v_words.add(element.substring(0,index)); v_hints.add(element.substring(index +1)); phrases.remove(index); System.out.print(index); } The FileUtilities file was given to us by the pofessor, here it is. import java.util.*; import java.io.*; public class FileUtilities { private static final String FILE_NAME = "javawords.txt"; //------------------ getStrings ------------------------- // // returns a Vector of Strings // Each string is of the form: word:hint // where word contains no spaces. // The words and hints are read from FILE_NAME // // public static Vector<String> getStrings ( ) { Vector<String> words = new Vector<String>(); File file = new File( FILE_NAME ); Scanner scanFile; try { scanFile = new Scanner( file); } catch ( IOException e) { System.err.println( "LineInput Error: " + e.getMessage() ); return null; } while ( scanFile.hasNextLine() ) { // read the word and follow it by a colon String s = scanFile.nextLine().trim().toUpperCase() + ":"; if( s.length()>1 && scanFile.hasNextLine() ) { // append the hint and add to collection s+= scanFile.nextLine().trim(); words.add(s); } } // shuffle Collections.shuffle(words); return words; } }

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• Quickly Copy Movie Files to Individually Named Folders

  - by DigitalGeekery

  Some HTPC media manager applications require movie files to be in stored in separate folders to properly store information such as cover art images and other metadata. Here we look at copying movie files to individual folders. If you already have a large movie collection stored in a single folder, we’ll show you how to quickly move those files into their own individually named folders. File2Folder FIle2folder is a handy portable app that automatically creates and moves movie files into a folder of the same filename. There is no installation needed. Simply download and run the .exe file (link below). Enter the current movie directory, or browse for the folder. File2folder now supports both local and network shares. When you are ready to create the folders and move the files, click Move! You’ll see the move progress displayed in the window. When the process is finished, you’ll have all your movie file in individual folders.   Change your mind? Just click the Undo! button…   …and the move and folder creation process will be undone. If you would like to have the folder monitored for new files, click the Start button. File2folder will process any new files it discovers every 180 seconds. To turn it off, click Stop. This simple little program is a huge timesaver for those looking to organize movie collections for their HTPC. We should also note that this will work with any files, not just videos. Download file2folder Similar Articles Productive Geek Tips Hack: Turn Off Debug Mode in VMWare Workstation 6 BetaAdd Images and Metadata to Windows 7 Media Center Movie LibraryAdd Folders to the Movie Library in Windows 7 Media CenterAutomatically Mount and View ISO files in Windows 7 Media CenterMove the Public Folder in Windows Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips HippoRemote Pro 2.2 Xobni Plus for Outlook All My Movies 5.9 CloudBerry Online Backup 1.5 for Windows Home Server Identify Fonts using WhatFontis.com Windows 7’s WordPad is Actually Good Greate Image Viewing and Management with Zoner Photo Studio Free Windows Media Player Plus! – Cool WMP Enhancer Get Your Team’s World Cup Schedule In Google Calendar Backup Drivers With Driver Magician

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• Rotate camera around player and set new forward directions

  - by Samurai Fox

  I have a 3rd person camera which can rotate around the player. When I look at the back of the player and press forward, player goes forward. Then I rotate 360 around the player and "forward direction" is tilted for 90 degrees. So every 360 turn there is 90 degrees of direction change. For example when camera is facing the right side of the player, when I press button to move forward, I want player to turn to the left and make that the "new forward". I have Player object with Camera as child object. Camera object has Camera script. Inside Camera script there are Player and Camera classes. Player object itself, has Input Controller. Also I'm making this script for joystick/ controller primarily. My camera script so far: using UnityEngine; using System.Collections; public class CameraScript : MonoBehaviour { public GameObject Target; public float RotateSpeed = 10, FollowDistance = 20, FollowHeight = 10; float RotateSpeedPerTime, DesiredRotationAngle, DesiredHeight, CurrentRotationAngle, CurrentHeight, Yaw, Pitch; Quaternion CurrentRotation; void LateUpdate() { RotateSpeedPerTime = RotateSpeed * Time.deltaTime; DesiredRotationAngle = Target.transform.eulerAngles.y; DesiredHeight = Target.transform.position.y + FollowHeight; CurrentRotationAngle = transform.eulerAngles.y; CurrentHeight = transform.position.y; CurrentRotationAngle = Mathf.LerpAngle(CurrentRotationAngle, DesiredRotationAngle, 0); CurrentHeight = Mathf.Lerp(CurrentHeight, DesiredHeight, 0); CurrentRotation = Quaternion.Euler(0, CurrentRotationAngle, 0); transform.position = Target.transform.position; transform.position -= CurrentRotation * Vector3.forward * FollowDistance; transform.position = new Vector3(transform.position.x, CurrentHeight, transform.position.z); Yaw = Input.GetAxis("Right Horizontal") * RotateSpeedPerTime; Pitch = Input.GetAxis("Right Vertical") * RotateSpeedPerTime; transform.Translate(new Vector3(Yaw, -Pitch, 0)); transform.position = new Vector3(transform.position.x, transform.position.y, transform.position.z); transform.LookAt(Target.transform); } }

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• F# Project Euler Problem 1

  - by MarkPearl

  Every now and then I give project Euler a quick browse. Since I have been playing with F# I have found it a great way to learn the basics of the language. Today I thought I would give problem 1 an attempt… Problem 1 If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. My F# Solution I broke this problem into two functions… 1) be able to generate a collection of numbers that are multiples of a number but but are smaller than another number. let GenerateMultiplesOfXbelowY X Y = X |> Seq.unfold (fun i -> if (i<Y) then Some(i, i+X) else None) I then needed something that generated collections for multiples of 3 & 5 and then removed any duplicates. Once this was done I would need to sum these all together to get a result. I found the Seq object to be extremely useful to achieve this… let Multiples = Seq.append (GenerateMultiplesOfXbelowY 3 1000) (GenerateMultiplesOfXbelowY 5 1000) |> Seq.distinct |> Seq.fold(fun acc a -> acc + a) 0 |> Console.WriteLine |> Console.ReadLine My complete solution was … open System let GenerateMultiplesOfXbelowY X Y = X |> Seq.unfold (fun i -> if (i<Y) then Some(i, i+X) else None) let Multiples = Seq.append (GenerateMultiplesOfXbelowY 3 1000) (GenerateMultiplesOfXbelowY 5 1000) |> Seq.distinct |> Seq.fold(fun acc a -> acc + a) 0 |> Console.WriteLine |> Console.ReadLine   Which seemed to generate the correct result in a relatively short period of time although I am sure I will get some comments from the experts who know of some intrinsic method to achieve all of this in one method call.

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• Top down space game control problem

  - by Phil

  As the title suggests I'm developing a top down space game. I'm not looking to use newtonian physics with the player controlled ship. I'm trying to achieve a control scheme somewhat similar to that of FlatSpace 2 (awesome game). I can't figure out how to achieve this feeling with keyboard controls as opposed to mouse controls though. Any suggestions? I'm using Unity3d and C# or javaScript (unityScript or whatever is the correct term) works fine if you want to drop some code examples. Edit: Of course I should describe FlatSpace 2's control scheme, sorry. You hold the mouse button down and move the mouse in the direction you want the ship to move in. But it's not the controls I don't know how to do but rather the feeling of a mix of driving a car and flying an aircraft. It's really well made. Youtube link: FlatSpace2 on iPhone I'm not developing an iPhone game but the video shows the principle of the movement style. Edit 2 As there seems to be a slight interest, I'll post the version of the code I've used to continue. It works good enough. Sometimes good enough is sufficient! using UnityEngine; using System.Collections; public class ShipMovement : MonoBehaviour { public float directionModifier; float shipRotationAngle; public float shipRotationSpeed = 0; public double thrustModifier; public double accelerationModifier; public double shipBaseAcceleration = 0; public Vector2 directionVector; public Vector2 accelerationVector = new Vector2(0,0); public Vector2 frictionVector = new Vector2(0,0); public int shipFriction = 0; public Vector2 shipSpeedVector; public Vector2 shipPositionVector; public Vector2 speedCap = new Vector2(0,0); void Update() { directionModifier = -Input.GetAxis("Horizontal"); shipRotationAngle += ( shipRotationSpeed * directionModifier ) * Time.deltaTime; thrustModifier = Input.GetAxis("Vertical"); accelerationModifier = ( ( shipBaseAcceleration * thrustModifier ) ) * Time.deltaTime; directionVector = new Vector2( Mathf.Cos(shipRotationAngle ), Mathf.Sin(shipRotationAngle) ); //accelerationVector = Vector2(directionVector.x * System.Convert.ToDouble(accelerationModifier), directionVector.y * System.Convert.ToDouble(accelerationModifier)); accelerationVector.x = directionVector.x * (float)accelerationModifier; accelerationVector.y = directionVector.y * (float)accelerationModifier; // Set friction based on how "floaty" controls you want shipSpeedVector.x *= 0.9f; //Use a variable here shipSpeedVector.y *= 0.9f; //<-- as well shipSpeedVector += accelerationVector; shipPositionVector += shipSpeedVector; gameObject.transform.position = new Vector3(shipPositionVector.x, 0, shipPositionVector.y); } }

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• Nails vs Screws (C# List vs Dictionary)

  - by MarkPearl

  General This may sound like a typical noob statement, but I’m finding out in a very real way that just because you have a solution to a problem, doesn’t necessarily mean it is the best solution. This was reiterated to me when a friend of mine suggested I look at using Dictionaries instead of Lists for a particular problem – he was right, I have always just assumed that because lists solved my problem I did not need to look elsewhere. So my new manifesto to counter this ageless problem is as follows… Look for a solution that will logically work Once you have a solution look for possible alternatives Decide why your current solution is the best approach compared to the alternatives If it is.. use it till something better comes along, if it isnt…. change What’s the difference between Lists & Dictionaries Both lists and dictionaries are used to store collections of data. Assume we had the following declarations… var dic = new Dictionary<string, long>(); var lst = new List<long>(); long data;   With a list, you simply add the item to the list and it will add the item to the end of the list. lst.Add(data); With a dictionary, you need to specify some sort of key and the data you want to add so that it can be uniquely identified. dic.Add(uniquekey, data);   Because with a dictionary you now have unique identifier, in the background they provide all sort’s of optimized algorithms to find your associated data. What this means is that if you are wanting to access your data it is a lot faster than a List. So when is it appropriate to use either class? For me, if I can guarantee that each item in my collection will have a unique identifier, then I will use Dictionaries instead of Lists as there is a considerable performance benefit when accessing each data item. If I cannot make this sort of guarantee, then by default I will use a list. I know this is all really basic, and I hope I haven’t missed some fundamental principle… If anyone would like to add their 2 cents, please feel free to do so…

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• Asynchronously returning a hierarchal data using .NET TPL... what should my return object "look" like?

  - by makerofthings7

  I want to use the .NET TPL to asynchronously do a DIR /S and search each subdirectory on a hard drive, and want to search for a word in each file... what should my API look like? In this scenario I know that each sub directory will have 0..10000 files or 0...10000 directories. I know the tree is unbalanced and want to return data (in relation to its position in the hierarchy) as soon as it's available. I am interested in getting data as quickly as possible, but also want to update that result if "better" data is found (better means closer to the root of c:) I may also be interested in finding all matches in relation to its position in the hierarchy. (akin to a report) Question: How should I return data to my caller? My first guess is that I think I need a shared object that will maintain the current "status" of the traversal (started | notstarted | complete ) , and might base it on the System.Collections.Concurrent. Another idea that I'm considering is the consumer/producer pattern (which ConcurrentCollections can handle) however I'm not sure what the objects "look" like. Optional Logical Constraint: The API doesn't have to address this, but in my "real world" design, if a directory has files, then only one file will ever contain the word I'm looking for.  If someone were to literally do a DIR /S as described above then they would need to account for more than one matching file per subdirectory. More information : I'm using Azure Tables to store a hierarchy of data using these TPL extension methods. A "node" is a table. Not only does each node in the hierarchy have a relation to any number of nodes, but it's possible for each node to have a reciprocal link back to any other node. This may have issues with recursion but I'm addressing that with a shared object in my recursion loop. Note that each "node" also has the ability to store local data unique to that node. It is this information that I'm searching for. In other words, I'm searching for a specific fixed RowKey in a hierarchy of nodes. When I search for the fixed RowKey in the hierarchy I'm interested in getting the results FAST (first node found) but prefer data that is "closer" to the starting point of the hierarchy. Since many nodes may have the particular RowKey I'm interested in, sometimes I may want to get a report of ALL the nodes that contain this RowKey.

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• From 20,663 issues to 1 issue&ndash;style-copping C5.Tests

  - by TATWORTH

  Originally posted on: http://geekswithblogs.net/TATWORTH/archive/2014/05/28/from-20663-issues-to-1-issuendashstyle-copping-c5.tests.aspxI recently became interested in the potential of the C5 Collections solution from http://www.itu.dk/research/c5/, however I was dismayed at the state of the code in the unit test project, so I set about fixing the 20,663 issues detected by StyleCop. The tools I used were the latest versions of: My 64-bit development PC running Windows 8 Update with 8Gb RAM Visual Studio 2013 Ultimate with SP2 ReSharper GhostDoc Pro My first attempt had to be abandoned due to collision of class names which broke one of the unit tests. So being aware of this duplication of class names, I started again and planned to prepend the class names with the namespace name. In some cases I additionally prepended the item of the C5 collection that was being tested. So what was the condition of code at the start? Besides the sprawl of C# code not written to style cop standard, there was: 1) Placing of many classes within one physical file. 2) Namespace within name space that did not follow the project structure. 3) As already mentioned, duplication of class names across namespaces. 4) A copyright notice that spawled but had to be preserved. 5) Project sub-folders were all lower case instead of initial letter capitalised. The first step was to add a stylecop heading plus the original heading contained within a region, to every file. The next step was to run GhostDoc Pro using its “Document File” option on every file but not letting it replace the headers, I had added. This brought the number of issues down to 18,192. I then went through each file collapsing each class and prepending names as appropriate. At each step, I saved the changes to my local Git. The step was to move each class to its own file and to style-cop each file. ReSharper provides a very useful feature for doing this which also fixes missing “this.” and moves using statements inside the namespace. Some classes required minimal work whereas others required extensive work to reach the stylecop standard. The unit tests were run at each split and when each class was completed. When all was done, one issue remained which I will need to submit to stylecop team for their advice (and possibly a fix to stylecop). The updated solution has been made available at https://c5stylecopped.codeplex.com/releases/view/122785.

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• Flattening System.Web.UI ControlCollection

  - by evovision

  Hi,   Sometimes one may need to get a list of child controls inside specific container and don't care about the underlying hierarchy.   The result is beautifully achieved using this extension method:   using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;    public static class ControlCollectionExtensionMethods    {        public static IEnumerable<Control> FlattenedList(this ControlCollection controls)        {            foreach (Control ctrl in controls)            {                  // return parent control                   yield return ctrl;                              // and dive into child collection                   foreach (Control child in ctrl.Controls.FlattenedList())                         yield return child;            }        }    }   P.S.: don't forget about namespaces when using it in your code, if above class is wrapped into namespace, for example: Sample, the source code file with calling code must explicitly reference it: using Sample;

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• Synchronize the same set of files to 2 different locations with 2 different programs for 2 different purposes

  - by Hedgetrimmer

  Because of stupid questionable IT policies at my not-to-be-named place of occupation, I have been (and will be, for the forseeable future) carrying on an external hard drive a unison-synchronized copy of all of my documents and code, including code which resides in some of my "dotfiles" and other code which resides in ~/bin (things I've made are there because ~/bin is in my $PATH) along with some cruft generated (and to be generated) by conscript and its related "giter8" templating system for Scala project boilerplates. Despite this, I do use a symlinking program to store all of my important dotfiles in a subdirectory. Thanks to that somewhat complicated setup, I have resorted to making a directory full of symlinks to every directory (or file, as is the case with stuff under ~/bin) that I want synchronized, and then follow = True is in my unison profile. It happens to be that this collection of odds and ends—plus an automatically-generated text file containing every package installed on my system—is everything under ~ that needs to be backed up to a remote (rsync-over-ssh) host with client-side encryption and signing from GPG. I already believe that duplicity is the most appropriate program to do that. What isn't as clear-cut is how to make duplicity use the exact same set of files when it runs a backup; it would be simple if duplicity would follow symlinks, but it does not and the manpage lists no option for enabling any such behavior. Comparing unison's file selection algorithm to duplicity's, I don't think I can write a program that could compute a ruleset for one program given one for the other. For the record, I would rather not keep the symlinks manually synchronized with duplicity file-selection rules, as they can change thanks to the above-mentioned complications regarding ~/bin. I don't think running duplicity on the external hard disk is such a good idea either; I usually keep that hard disk unmounted and unplugged in case of a power failure or other physical problem with the computer, plus I'm not sure about duplicity's performance given that: the hard disk is NTFS-formatted in order to be useable at my Windows-imprisoned place of occupation. despite being a USB 3.0 disk, my computer has no USB 3.0 ports so it acts as a USB 2.0 disk. How can I have duplicity (or is there a better program that I have overlooked?) back up the exact same set of files that is bidirectionally synchronized with my external hard disk?

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• Setting up PerformancePoint Services on Sharepoint 2010: connection errors

  - by Rik

  I have tried to setup PerformancePoint Services on SharePoint 2010, but every time I try to use the dashboard designer, I get this error: “An error has occurred attempting to contact the specified SharePoint site” I have tried these steps but it hasn't helped. Any ideas? The event log gives the following information: WebHost failed to process a request. Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/24724999 Exception: System.ServiceModel.ServiceActivationException: The service '/_vti_bin/client.svc' cannot be activated due to an exception during compilation. The exception message is: This collection already contains an address with scheme http. There can be at most one address per scheme in this collection. Parameter name: item. --- System.ArgumentException: This collection already contains an address with scheme http. There can be at most one address per scheme in this collection. Parameter name: item at System.ServiceModel.UriSchemeKeyedCollection.InsertItem(Int32 index, Uri item) at System.Collections.Generic.SynchronizedCollection`1.Add(T item) at System.ServiceModel.UriSchemeKeyedCollection..ctor(Uri[] addresses) at System.ServiceModel.ServiceHost..ctor(Type serviceType, Uri[] baseAddresses) at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses) at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) --- End of inner exception stack trace --- at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.EnsureServiceAvailableFast(String relativeVirtualPath) Process Name: w3wp Process ID: 2576

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• start-stop-daemon can't find executable that's right in front of it

  - by Bart van Heukelom

  root@mountain-lion:/opt/smartfox# ls -lha total 180K drwxr-xr-x 8 root root 4.0K 2012-06-01 14:09 . drwxr-xr-x 4 root root 4.0K 2012-06-01 09:41 .. drwxr-xr-x 8 root root 4.0K 2009-05-17 21:57 lib lrwxrwxrwx 1 root root 22 2012-06-01 09:41 logs -> /var/opt/smartfox/logs -rwxr-xr-x 1 root root 1.4K 2012-06-01 14:28 run.sh root@mountain-lion:/opt/smartfox# cat run.sh #!/bin/bash java -cp "./:./sfsExtensions/:lib/activation.jar:lib/commons-beanutils.jar:lib/commons-collections-3.2.jar:lib/commons-dbcp-1.2.1.jar:lib/commons-lang-2.3.jar:lib/commons-logging-1.1.jar:lib/commons-pool-1.2.jar:lib/concurrent.jar:lib/ezmorph-1.0.3.jar:lib/h2.jar:lib/js.jar:lib/json-lib-2.1-jdk15.jar:lib/json.jar:lib/jsr173_1.0_api.jar:lib/jysfs.jar:lib/jython.jar:lib/nanoxml-2.2.1.jar:lib/wrapper.jar:lib/xbean.jar:lib/javamail/imap.jar:lib/javamail/mailapi.jar:lib/javamail/pop3.jar:lib/javamail/smtp.jar:lib/jetty/jetty.jar:lib/jetty/jetty-util.jar:lib/jetty/jstl.jar:lib/jetty/multipartrequest.jar:lib/jetty/servlet-api.jar:lib/jetty/standard.jar:lib/jsp-2.1/commons-el-1.0.jar:lib/jsp-2.1/core-3.1.0.jar:lib/jsp-2.1/jsp-2.1.jar:lib/jsp-2.1/jsp-api-2.1.jar:lib/jsp-2.1/jstl.jar:lib/jsp-2.1/standard.jar:lib/lsc.jar:lib/commons-io-1.4.jar" \ it.gotoandplay.smartfoxserver.SmartFoxServer > logs/smartfox.out 2>&1 & JAVAPID=$! echo "Started Smartfox. JVM PID = $JAVAPID" trap "echo Stopping Smartfox.; kill $JAVAPID" INT TERM wait echo "Smartfox stopped." root@mountain-lion:/opt/smartfox# start-stop-daemon --start --make-pidfile --pidfile /var/opt/smartfox/smartfox.pid --exec ./run.sh start-stop-daemon: unable to start ./run.sh (No such file or directory) Why can't start-stop-daemon find the script?

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• SharePoint Backup/Restore without stsadm

  - by Kevin

  Due to problems we found with the restore of sites/site collections using stsadm (our tasks generated from workflows were not restored), we've taken a different route for backup/restore. We plan a major customization to our SP site and want to take a backup so we can rollback in case the install fails. In our System Testing (not production) environment, we've backed up the 12 hive, the virtual dir's that the IIS points to SharePoint, and the SharePoint databases in SQL (using SQL server to do the db backups). We have custom event handlers and workflows built with Visual Studio, and deploy the dlls to the GAC as version 2 (signed and versioned in Visual Studio). So when we deploy, the GAC will contain 2 versions of the workflows - version 1 and version 2. During the deploy we use SP stsadm features to install/activate the WF's. We also go to each library and add the new, version 2 WFs. This automatically sets the version 1 WF's to "Not Allow" new instances (which is what we want) and the version 2 as active - perfect so far. When we've completed the install, we then assume a failure and attempt to restore to the same machines (SharePoint on one server, SQL on another). We start by uninstalling the version 2 WF's from the GAC, reset IIS (to clear cache of these ver. 2 WF dlls'), restore the 12-hive and virtual directory folders, then restore the SQL dbs. This is all just as manual as you read it - no stsadm here. All seems to work after our restore, it appears the restore was successful - the mods we made to column names, data changes, etc during the install are all reverted back to the original pre-install state. With one exception. When we run a workflow, it always fails and the Logs in the 12-hive indicates the WF is still trying to use the version 2 of the dll (System.IO file not found error) We think we've backed up and restored all the moving pieces of Sharepoint but we're missing something here, does anybody have any ideas why the version 2 WF dlls are still being referenced eventhough we restored all the folders and db's of SharePoint? Thanks, Kevin

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• Fatal Execution Engine Error on the Windows2008 r2, IIS7.5

  - by user66524

  Hi Guys We are running some asp.net(3.5) applications on the Windows2008 r2, IIS7.5. Recently we got some event logs so difficult, we have not idea hope some guys can help. 1.EventID: 1334 (9-1-2011 8:41:57) Error message An error occurred during a process host idle check. Exception: System.AccessViolationException Message: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. StackTrace: at System.Collections.Hashtable.GetEnumerator() at System.Web.Hosting.ApplicationManager.IsIdle() at System.Web.Hosting.ProcessHost.IsIdle() 2.EventID: 1023 (9-1-2011 19:44:02) Error message .NET Runtime version 2.0.50727.4952 - Fatal Execution Engine Error (742B851A) (80131506) 3.EventID: 1000 (9-1-2011 19:44:03) Error message Faulting application name: w3wp.exe, version: 7.5.7600.16385, time stamp: 0x4a5bcd2b Faulting module name: mscorwks.dll, version: 2.0.50727.4952, time stamp: 0x4bebd49a Exception code: 0xc0000005 Fault offset: 0x0000c262 Faulting process id: 0x%9 Faulting application start time: 0x%10 Faulting application path: %11 Faulting module path: %12 Report Id: %13 4.EventID: 5011 (9-1-2011 19:44:03) Error message A process serving application pool 'AppPoolName' suffered a fatal communication error with the Windows Process Activation Service. The process id was '2552'. The data field contains the error number. 5.some info: we got the memory.hdmp(234MB) and minidump.mdmp(19.2) from control panel action center but I donot know how to use that :(

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• Why Is ModSecurity Unable to Access the Data Directory?

  - by tommytwoeyes

  Update I think we've solved this; the problem appears to have been a result of the /modsec_storage directory having an incorrect value for its SELinux context type. However, we're still not sure, because although after I changed the SELinux context type value, Apache was able to create files in that directory for the global and ip collections (global.dir/global.pag and ip.dir/ip.pag), the new files still have zero bytes. I'm new to ModSecurity and am not sure if the files are empty because something is wrong with the configuration or if ModSecurity has simply determined it doesn't need to store IP addresses persistently after each transaction ends. Anyone able to offer guidance here? I've recently installed ModSecurity (v2.5.12 / CRS v2.0.8) on our production server, and everything works great, except for these errors that it keeps writing to the Apache error log: Failed to access DBM file "/modsec_storage/global": Permission denied [hostname "www.internationalstudent.com"] [uri "/includes/soc_bookmarks/images/delicious.png"] [unique_id "LZ6jc38AAAEAAFO6408AAABO"] Failed to access DBM file "/modsec_storage/ip": Permission denied [hostname "www.internationalstudent.com"] [uri "/includes/soc_bookmarks/images/delicious.png"] [unique_id "LZ6jc38AAAEAAFO6408AAABO"] After following the instructions for file permission settings in the ModSecurity handbook by Ivan Ristic, with no success, I created a /modsec_storage directory, set the owner & group to apache, and set the permissions for the directory recursively to 777. However, ModSecurity is still reporting the same permission errors, so I am stumped. Can anyone tell me how to fix this?

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• Windows Task Scheduler fails on EventData instruction

  - by Pete

  The Scheduled Task fails on the Event Data instruction in this XML: <ValueQueries> <Value name="eventChannel">Event/System/Channel</Value> <Value name="eventRecordID">Event/System/EventRecordID</Value> <Value name="eventData">Event/EventData/Data</Value> </ValueQueries> The other 2 fields can be passed as arguments and the EventData syntax matches other websites, so I don't know why it's failing. This is the Event Viewer XML: <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event"> <System> <Provider Name="Aptify.ExceptionManagerPublishedException" /> <EventID Qualifiers="0">0</EventID> <Level>2</Level> <Task>0</Task> <Keywords>0x80000000000000</Keywords> <TimeCreated SystemTime="2013-11-07T19:39:14.000000000Z" /> <EventRecordID>97555</EventRecordID> <Channel>Application</Channel> <Computer>[Computer Name]</Computer> <Security /> </System> <EventData> <Data>General Information ********************************************* Additional Info: ExceptionManager.MachineName: [Computer Name] ExceptionManager.TimeStamp: 11/7/2013 12:39:14 PM ExceptionManager.FullName: AptifyExceptionManagement, Version=4.0.0.0, Culture=neutral, PublicKeyToken=[key] ExceptionManager.AppDomainName: Aptify Shell.exe ExceptionManager.ThreadIdentity: ExceptionManager.WindowsIdentity: ACA_DOMAIN\pbassett 1) Exception Information ********************************************* Exception Type: Aptify.Framework.BusinessLogic.GenericEntity.AptifyGenericEntityValidationException Entity: Tasks ErrorString: Task Type "Make Contact" is not active. MachineName: [machine] CreatedDateTime: 11/7/2013 12:39:14 PM AppDomainName: Aptify Shell.exe ThreadIdentityName: WindowsIdentityName: [identity] Severity: 0 ErrorNumber: 0 Message: Task Type "Make Contact" is not active. Data: System.Collections.ListDictionaryInternal TargetSite: Boolean Save(Boolean, System.String ByRef, Sys tem.String) HelpLink: NULL Source: AptifyGenericEntity StackTrace Information ********************************************* at Aptify.Framework.BusinessLogic.GenericEntity.AptifyGenericEntity.Save(Boolean AllowGUI, String& ErrorString, String TransactionID)</Data> </EventData> </Event>

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• Fatal Execution Engine Error on the Windows2008 r2, IIS7.5

  - by user66524

  Hi Guys We are running some asp.net(3.5) applications on the Windows2008 r2, IIS7.5. Recently we got some event logs so difficult, we have not idea hope some guys can help. 1.EventID: 1334 (9-1-2011 8:41:57) Error message An error occurred during a process host idle check. Exception: System.AccessViolationException Message: Attempted to read or write protected memory. This is often an indication that other memory is corrupt. StackTrace: at System.Collections.Hashtable.GetEnumerator() at System.Web.Hosting.ApplicationManager.IsIdle() at System.Web.Hosting.ProcessHost.IsIdle() 2.EventID: 1023 (9-1-2011 19:44:02) Error message .NET Runtime version 2.0.50727.4952 - Fatal Execution Engine Error (742B851A) (80131506) 3.EventID: 1000 (9-1-2011 19:44:03) Error message Faulting application name: w3wp.exe, version: 7.5.7600.16385, time stamp: 0x4a5bcd2b Faulting module name: mscorwks.dll, version: 2.0.50727.4952, time stamp: 0x4bebd49a Exception code: 0xc0000005 Fault offset: 0x0000c262 Faulting process id: 0x%9 Faulting application start time: 0x%10 Faulting application path: %11 Faulting module path: %12 Report Id: %13 4.EventID: 5011 (9-1-2011 19:44:03) Error message A process serving application pool 'AppPoolName' suffered a fatal communication error with the Windows Process Activation Service. The process id was '2552'. The data field contains the error number. 5.some info: we got the memory.hdmp(234MB) and minidump.mdmp(19.2) from control panel action center but I donot know how to use that :(

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• IBM Keynote: (hardware,software)–>{IBM.java.patterns}

  - by Janice J. Heiss

  On Sunday evening, September 30, 2012, Jason McGee, IBM Distinguished Engineer and Chief Architect Cloud Computing, along with John Duimovich IBM Distinguished Engineer and Java CTO, gave an information- and idea-rich keynote that left Java developers with much to ponder.Their focus was on the challenges to make Java more efficient and productive given the hardware and software environments of 2012. “One idea that is very interesting is the idea of multi-tenancy,” said McGee, “and how we can move up the spectrum. In traditional systems, we ran applications on dedicated middleware, operating systems and hardware. A lot of customers still run that way. Now people introduce hardware virtualization and share the hardware. That is good but there is a lot more we can do. We can share middleware and the application itself.” McGee challenged developers to better enable the Java language to function in these higher density models. He spoke about the need to describe patterns that help us grasp the full environment that an application needs, whether it’s a web or full enterprise application. Developers need to understand the resources that an application interacts with in a way that is simple and straightforward. The task is to then automate that deployment so that the complexity of infrastructure can be by-passed and developers can live in a simpler world where the cloud can automatically configure the needed environment. McGee argued that the key, something IBM has been working on, is to use a simpler pattern that allows a cloud-based architecture to embrace the entire infrastructure required for an application and make it highly available, scalable and able to recover from failure. The cloud-based architecture would automate the complexity of setting up and managing the infrastructure. IBM has been trying to realize this vision for customers so they can describe their Java application environment simply and allow the cloud to automate the deployment and management of applications. “The point,” explained McGee, “is to package the executable used to describe applications, to drop it into a shared system and let that system provide some intelligence about how to deploy and manage those applications.”John Duimovich on Improvements in JavaMcGee then brought onstage IBM’s Distinguished Engineer and CTO for Java, John Duimovich, who showed the audience ways to deploy Java applications more efficiently.Duimovich explained that, “When you run lots of copies of Java in the cloud or any hypervisor virtualized system, there are a lot of duplications of code and jar files. IBM has a facility called ‘shared classes’ where we put shared code, read only artefacts in a cache that is sharable across hypervisors.” By putting JIT code in ahead of time, he explained that the application server will use 20% less memory and operate 30% faster.  He described another example of how the JVM allows for the maximum amount of sharing that manages the tenants and file sockets and memory use through throttling and control. Duimovich touched on the “thin is in” model and IBM’s Liberty Profile and lightweight runtime for the cloud, which allows for greater efficiency in interacting with the cloud.Duimovich discussed the confusion Java developers experience when, for example, the hypervisor tells them that that they have 8 and then 4 and then 16 cores. “Because hypervisors are virtualized, they can change based on resource needs across the hypervisor layer. You may have 10 instances of an operation system and you may need to reallocate memory, " explained Duimovich.  He showed how to resize LPARs, reallocate CPUs and migrate applications as needed. He explained how application servers can resize thread pools and better use resources based on information from the hypervisors.Java Challenges in Hardware and SoftwareMcGee ended the keynote with a summary of upcoming hardware and software challenges for the Java platform. He noted that one reason developers love Java is it allows them to ignore differences in hardware. He stated that the most important things happening in hardware were in network and storage – in developments such as the speed of SSD, the exploitation of high-speed, low-latency networking, and recent developments such as storage-class memory, and non-volatile main memory. “So we are challenged to maintain the benefits of Java and the abstraction it provides from hardware while still exploiting the new innovations in hardware,” said McGee.McGee discussed transactional messaging applications where developers send messages transactionally persist a message to storage, something traditionally done by backing messages on spinning disks, something mostly outdated. “Now,” he pointed out, “we would use SSD and store it in Flash and get 70,000 messages a second. If we stored it using a PCI express-based flash memory device, it is still Flash but put on a PCI express bus on a card closer to the CPU. This way I get 300,000 messages a second and 25% improvement in latency.” McGee’s central point was that hardware has a huge impact on the performance and scalability of applications. New technologies are enabling developers to build classes of Java applications previously unheard of. “We need to be able to balance these things in Java – we need to maintain the abstraction but also be able to exploit the evolution of hardware technology,” said McGee. According to McGee, IBM's current focus is on systems wherein hardware and software are shipped together in what are called Expert Integrated Systems – systems that are pre-optimized, and pre-integrated together. McGee closed IBM’s engaging and thought-provoking keynote by pointing out that the use of Java in complex applications is increasingly being augmented by a host of other languages with strong communities around them – JavaScript, JRuby, Scala, Python and so forth. Java developers now must understand the strengths and weaknesses of such newcomers as applications increasingly involve a complex interconnection of languages.

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• Blog Buzz - Devoxx 2011

  - by Janice J. Heiss

  Some day I will make it to Devoxx – for now, I’m content to vicariously follow the blogs of attendees and pick up on what’s happening.  I’ve been doing more blog "fishing," looking for the best commentary on 2011 Devoxx. There’s plenty of food for thought – and the ideas are not half-baked.The bloggers are out in full, offering useful summaries and commentary on Devoxx goings-on.Constantin Partac, a Java developer and a member of Transylvania JUG, a community from Cluj-Napoca/Romania, offers an excellent summary of the Devoxx keynotes. Here’s a sample:“Oracle Opening Keynote and JDK 7, 8, and 9 Presentation•    Oracle is committed to Java and wants to provide support for it on any device.•    JSE 7 for Mac will be released next week.•    Oracle would like Java developers to be involved in JCP, to adopt a JSR and to attend local JUG meetings.•    JEE 7 will be released next year.•    JEE 7 is focused on cloud integration, some of the features are already implemented in glassfish 4 development branch.•    JSE 8 will be release in summer of 2013 due to “enterprise community request” as they can not keep the pace with an 18    month release cycle.•    The main features included in JSE8 are lambda support, project Jigsaw, new Date/Time API, project Coin++ and adding   support for sensors. JSE 9 probably will focus on some of these features:1.    self tuning JVM2.    improved native language integration3.    processing enhancement for big data4.    reification (adding runtime class type info for generic types)5.    unification of primitive and corresponding object classes6.    meta-object protocol in order to use type and methods define in other JVM languages7.    multi-tenancy8.    JVM resource management” Thanks Constantin! Ivan St. Ivanov, of SAP Labs Bulgaria, also commented on the keynotes with a different focus.  He summarizes Henrik Stahl’s look ahead to Java SE 8 and JavaFX 3.0; Cameron Purdy on Java EE and the cloud; celebrated Java Champion Josh Bloch on what’s good and bad about Java; Mark Reinhold’s quick look ahead to Java SE 9; and Brian Goetz on lambdas and default methods in Java SE 8. Here’s St. Ivanov’s account of Josh Bloch’s comments on the pluses of Java:“He started with the virtues of the platform. To name a few:    Tightly specified language primitives and evaluation order – int is always 32 bits and operations are executed always from left  to right, without compilers messing around    Dynamic linking – when you change a class, you need to recompile and rebuild just the jar that has it and not the whole application    Syntax  similarity with C/C++ – most existing developers at that time felt like at home    Object orientations – it was cool at that time as well as functional programming is today    It was statically typed language – helps in faster runtime, better IDE support, etc.    No operator overloading – well, I’m not sure why it is good. Scala has it for example and that’s why it is far better for defining DSLs. But I will not argue with Josh.”It’s worth checking out St. Ivanov’s summary of Bloch’s views on what’s not so great about Java as well. What's Coming in JAX-RS 2.0Marek Potociar, Principal Software Engineer at Oracle and currently specification lead of Java EE RESTful web services API (JAX-RS), blogged on his talk about what's coming in JAX-RS 2.0, scheduled for final release in mid-2012.  Here’s a taste:“Perhaps the most wanted addition to the JAX-RS is the Client API, that would complete the JAX-RS story, that is currently server-side only. In JAX-RS 2.0 we are adding a completely interface-based and fluent client API that blends nicely in with the existing fluent response builder pattern on the server-side. When we started with the client API, the first proposal contained around 30 classes. Thanks to the feedback from our Expert Group we managed to reduce the number of API classes to 14 (2 of them being exceptions)! The resulting is compact while at the same time we still managed to create an API that reflects the method invocation context flow (e.g. once you decide on the target URI and start setting headers on the request, your IDE will not try to offer you a URI setter in the code completion). This is a subtle but very important usability aspect of an API…” Obviously, Devoxx is a great Java conference, one that is hitting this year at a time when much is brewing in the platform and beginning to be anticipated.

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• Replicated MongoDB server slower than simple shards

  - by displayName

  I tried to compare the performance of a sharded configuration against a sharded and replicated configuration. The sharded configuration consists of 8 shards each running on three different machines thereby constituting a total of 24 shards. All 8 of these shards run in the same partition on each machine. The sharded and replicated version is 8 shards again just like plain sharding, and all 8 mongods run on the same partition in each machine. But apart from this, each of these three machine now run additional 16 threads on another partition which serve as the secondary for the 8 mongods running on other machines. This is the way I prepared a sharded and replicated configuration with data chunks having replication factor of 3. Important point to note is that once the data has been loaded, it is not modified. So after primary and secondaries have synchronized then it doesn't matter which one i read from. To run the queries, I use an entirely different machine (let's call it config) which runs mongos and this machine's only purpose is to receive queries and run them on the cluster. Contrary to my expectations, plain sharding of 8 threads on each machine (total = 3 * 8 = 24) is performing better for queries than the sharded + replicated configuration. I have a script written to perform the query. So in order to time the scripts, I use time ./testScript and see the result. I tried changing the reading preference for replicated cluster by logging to mongo of config and run db.getMongo().setReadPref('secondary') and then exit the shell and run the queries like time ./testScript. The questions are: Where am i going wrong in the replication? Why is it slower than its plain sharding version? Does the db.getMongo().ReadPref('secondary') persist when i leave the shell and try to perform the query? All the four machines are running Linux and i have already increased the ulimit -n to 2048 from initial value of 1024 to allow more connections. The collections are properly distributed and all the mongods have equal number of chunks. Goes without saying that indices in both configurations are the same.

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• Setting up PerformancePoint Services on Sharepoint 2010: connection errors

  - by Rik

  I have tried to setup PerformancePoint Services on SharePoint 2010, but every time I try to use the dashboard designer, I get this error: “An error has occurred attempting to contact the specified SharePoint site” I have tried these steps but it hasn't helped. Any ideas? The event log gives the following information: WebHost failed to process a request. Sender Information: System.ServiceModel.ServiceHostingEnvironment+HostingManager/24724999 Exception: System.ServiceModel.ServiceActivationException: The service '/_vti_bin/client.svc' cannot be activated due to an exception during compilation. The exception message is: This collection already contains an address with scheme http. There can be at most one address per scheme in this collection. Parameter name: item. --- System.ArgumentException: This collection already contains an address with scheme http. There can be at most one address per scheme in this collection. Parameter name: item at System.ServiceModel.UriSchemeKeyedCollection.InsertItem(Int32 index, Uri item) at System.Collections.Generic.SynchronizedCollection`1.Add(T item) at System.ServiceModel.UriSchemeKeyedCollection..ctor(Uri[] addresses) at System.ServiceModel.ServiceHost..ctor(Type serviceType, Uri[] baseAddresses) at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(Type serviceType, Uri[] baseAddresses) at System.ServiceModel.Activation.ServiceHostFactory.CreateServiceHost(String constructorString, Uri[] baseAddresses) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.CreateService(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.ActivateService(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) --- End of inner exception stack trace --- at System.ServiceModel.ServiceHostingEnvironment.HostingManager.EnsureServiceAvailable(String normalizedVirtualPath) at System.ServiceModel.ServiceHostingEnvironment.EnsureServiceAvailableFast(String relativeVirtualPath) Process Name: w3wp Process ID: 2576

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• One Active Directory, Multiple Remote Desktop Services (Server 2012 solution)

  - by Trinitrotoluene

  What I am trying to do is quite complex, so I figured I'd throw it out to a wider audience to see if anyone can find a flaw. What I am trying to do (as an MSP/VAR) is design a solution that will give multiple companies a session based remote desktop (companies that need to be kept completely seperate), using only a handful of servers. This is how I imagine it at the moment: CORE SERVER - Server 2012 Datacentre (All below are HyperV servers) Server1: Cloud-DC01 (Active Directory Domain Services for mycloud.local) Server2: Cloud-EX01 (Exchange Server 2010 running multi tenant mode) Server3: Cloud-SG01 (Remote Desktop Gateway) CORE SERVER 2 - Server 2012 Datacentre (All below are HyperV servers) Server1: Cloud-DC02 (Active Directory Domain Services for mycloud.local) Server2: Cloud-TS01 (Remote Desktop Session Host for Company A) Server3: Cloud-TS02 (Remote Desktop Session Host for Company B) Server4: Cloud-TS03 (Remote Desktop Session Host for Company C) What I thought about doing was setting up each Organisation in their own OU (perhaps creating their OU structure based on the Excahnge 2010 tenant OU structure so the accounts are linked). Each company would get a Remote Desktop Session Host server that would also serve as a file server. This server would be seperated from the rest on its own range. The server Cloud-SG01 would have access to all these networks and route the traffic to the appropriate network when a client connects and authenticated so they are pushed onto the correct server (Based on session collections in 2012). I won't lie this is something I have come up with quite quickly so there may well be something gapingly obvious that I am missing. Any feedback would be appreciated.

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• Session Report - Modern Software Development Anti-Patterns

  - by Janice J. Heiss

  In this standing-room-only session, building upon his 2011 JavaOne Rock Star “Diabolical Developer” session, Martijn Verburg, this time along with Ben Evans, identified and explored common “anti-patterns” – ways of doing things that keep developers from doing their best work. They emphasized the importance of social interaction and team communication, along with identifying certain psychological pitfalls that lead developers astray. Their emphasis was less on technical coding errors and more how to function well and to keep one’s focus on what really matters. They are the authors of the highly regarded The Well-Grounded Java Developer and are both movers and shakers in the London JUG community and on the Java Community Process. The large room was packed as they gave a fast-moving, witty presentation with lots of laughs and personal anecdotes. Below are a few of the anti-patterns they discussed.Anti-Pattern One: Conference-Driven DeliveryThe theme here is the belief that “Real pros hack code and write their slides minutes before their talks.” Their response to this anti-pattern is an expression popular in the military – PPPPPP, which stands for, “Proper preparation prevents piss-poor performance.”“Communication is very important – probably more important than the code you write,” claimed Verburg. “The more you speak in front of large groups of people the easier it gets, but it’s always important to do dry runs, to present to smaller groups. And important to be members of user groups where you can give presentations. It’s a great place to practice speaking skills; to gain new skills; get new contacts, to network.”They encouraged attendees to record themselves and listen to themselves giving a presentation. They advised them to start with a spouse or friends if need be. Learning to communicate to a group, they argued, is essential to being a successful developer. The emphasis here is that software development is a team activity and good, clear, accessible communication is essential to the functioning of software teams. Anti-Pattern Two: Mortgage-Driven Development The main theme here was that, in a period of worldwide recession and economic stagnation, people are concerned about keeping their jobs. So there is a tendency for developers to treat knowledge as power and not share what they know about their systems with their colleagues, so when it comes time to fix a problem in production, they will be the only one who knows how to fix it – and will have made themselves an indispensable cog in a machine so you cannot be fired. So developers avoid documentation at all costs, or if documentation is required, put it on a USB chip and lock it in a lock box. As in the first anti-pattern, the idea here is that communicating well with your colleagues is essential and documentation is a key part of this. Social interactions are essential. Both Verburg and Evans insisted that increasingly, year by year, successful software development is more about communication than the technical aspects of the craft. Developers who understand this are the ones who will have the most success. Anti-Pattern Three: Distracted by Shiny – Always Use the Latest Technology to Stay AheadThe temptation here is to pick out some obscure framework, try a bit of Scala, HTML5, and Clojure, and always use the latest technology and upgrade to the latest point release of everything. Don’t worry if something works poorly because you are ahead of the curve. Verburg and Evans insisted that there need to be sound reasons for everything a developer does. Developers should not bring in something simply because for some reason they just feel like it or because it’s new. They recommended a site run by a developer named Matt Raible with excellent comparison spread sheets regarding Web frameworks and other apps. They praised it as a useful tool to help developers in their decision-making processes. They pointed out that good developers sometimes make bad choices out of boredom, to add shiny things to their CV, out of frustration with existing processes, or just from a lack of understanding. They pointed out that some code may stay in a business system for 15 or 20 years, but not all code is created equal and some may change after 3 or 6 months. Developers need to know where the code they are contributing fits in. What is its likely lifespan? Anti-Pattern Four: Design-Driven Design The anti-pattern: If you want to impress your colleagues and bosses, use design patents left, right, and center – MVC, Session Facades, SOA, etc. Or the UML modeling suite from IBM, back in the day… Generate super fast code. And the more jargon you can talk when in the vicinity of the manager the better.Verburg shared a true story about a time when he was interviewing a guy for a job and asked him what his previous work was. The interviewee said that he essentially took patterns and uses an approved book of Enterprise Architecture Patterns and applied them. Verburg was dumbstruck that someone could have a job in which they took patterns from a book and applied them. He pointed out that the idea that design is a separate activity is simply wrong. He repeated a saying that he uses, “You should pay your junior developers for the lines of code they write and the things they add; you should pay your senior developers for what they take away.”He explained that by encouraging people to take things away, the code base gets simpler and reflects the actual business use cases developers are trying to solve, as opposed to the framework that is being imposed. He told another true story about a project to decommission a very long system. 98% of the code was decommissioned and people got a nice bonus. But the 2% remained on the mainframe so the 98% reduction in code resulted in zero reduction in costs, because the entire mainframe was needed to run the 2% that was left. There is an incentive to get rid of source code and subsystems when they are no longer needed. The session continued with several more anti-patterns that were equally insightful.

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