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  • How to know which image is being viewed in UIScrollView? Also, is it possible to loop scrolling for

    - by bruin
    This is what I'm trying to do, and I'm not sure if it's possible using UIScrollView. First, I don't care about zooming, all I care is that the user is able to scroll through images just like the Photo App, this I got. But how do I know which image he is viewing while using UIScrollView? For instance, if he stops on the 3rd image out of 10 images in the view, how do I know he's on that image? I can't find a way to access the index (is this accessible)?? Also, bonus question, once the user scrolls to the last image, I don't want the scrolling to stop but I want it to loop so that image 1 comes after image 10. And vice versa, if you scroll left passed image 1, you'll see image 10. I'm not asking for the logic, I can do this in an array very simply, I just don't know how to access (if it's even possible) the indexing of the images in the scroll view. If it's not, does anyone have a solution to do this? thanks in advance!

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  • Java - Removing duplicates in an ArrayList

    - by Will
    I'm working on a program that uses an ArrayList to store Strings. The program prompts the user with a menu and allows the user to choose an operation to perform. Such operations are adding Strings to the List, printing the entries etc. What I want to be able to do is create a method called removeDuplicates().This method will search the ArrayList and remove any duplicated values. I want to leave one instance of the duplicated value(s) within the list. I also want this method to return the total number of duplicates removed. I've been trying to use nested loops to accomplish this but I've been running into trouble because when entries get deleted, the indexing of the ArrayList gets altered and things don't work as they should. I know conceptually what I need to do but I'm having trouble implementing this idea in code. Here is some pseudo code: start with first entry; check each subsequent entry in the list and see if it matches the first entry; remove each subsequent entry in the list that matches the first entry; after all entries have been examined, move on to the second entry; check each entry in the list and see if it matches the second entry; remove each entry in the list that matches the second entry; repeat for entry in the list Here's the code I have so far: public int removeDuplicates() { int duplicates = 0; for ( int i = 0; i < strings.size(); i++ ) { for ( int j = 0; j < strings.size(); j++ ) { if ( i == j ) { // i & j refer to same entry so do nothing } else if ( strings.get( j ).equals( strings.get( i ) ) ) { strings.remove( j ); duplicates++; } } } return duplicates; }

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  • Wrapper class that creates objects at runtime and stores data in an array.

    - by scriptingalias
    I tried making a wrapper class that encapsulates an object, a string (for naming and differentiating the object instance), and an array to store data. The problem I'm having now is accessing this class using methods that determine the "name" of the object and also reading the array containing some random variables. import java.util.Arrays; import java.util.Random; public class WrapperClass { String varName; Object varData; int[] array = new int[10]; public WrapperClass(String name, Object data, int[] ARRAY) { varName = name; varData = data; array = ARRAY; } public static void getvalues() { } public static void main(String[] args) { int[] array = new int[10]; Random random = new Random(3134234); for(int i = 0; i < 10; i++) { for (int c = 0; c < 10; c++) { array[c] = random.nextInt();//randomly creates data } WrapperClass w = new WrapperClass("c" + i, new Object(),array); } } }

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  • How to implement Administrator rights in Java Application?

    - by Yatendra Goel
    I am developing a Data Modeling Software that is implemented in Java. This application converts the textual data (stored in a database) to graphical form so that users can interpret the data in a more efficient form. Now, this application will be accessed by 3 kinds of persons: 1. Managers (who can fill the database with data and they can also view the visual form of the data after entering the data into the database) 2. Viewers (who can only view the visual form of data that has been filled by managers) 3. Administrators (who can create and manage other administrators, managers and viewers) Now, how to implement 3 diff. views of the same application. Note: Managers, Viewers and Administrators can be located in any part of the world and should access the application through internet. One idea that came in my mind is as follows: Step1: Code all the business logic in EJBs so that it can be used in distributed environment (means which can be accessed by several users through internet) Step2: Code 3 Swing GUI Clients: One for administrators, one for managers and one for viewers. These 3 GUI clients can access business logic written in EJBs. Step3: Distribute the clients corresponding to their users. For instance, manager client to managers. =================================QUESTIONS======================================= Q1. Is the above approach is correct? Q2. This is very common functionality that various softwares have. So, Do they implement this kind of functionality through this way or any other way? Q3. If any other approach would be more better, then what is that approach?

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  • Is MarshalByRefObject special?

    - by Vilx-
    .NET has a thing called remoting where you can pass objects around between separate appdomains or even physical machines. I don't fully understand how the magic is done, hence this question. In remoting there are two base ways of passing objects around - either they can be serialized (converted to a bunch of bytes and the rebuilt at the other end) or they can inherit from MarshalByRefObject, in which case .NET makes some transparent proxies and all method calls are forwarded back to the original instance. This is pretty cool and works like magic. And I don't like magic in programming. Looking at the MarshalByRefObject with the Reflector I don't see anything that would set it apart from any other typical object. Not even a weird internal attribute or anything. So how is the whole transparent proxy thing organized? Can I make such a mechanism myself? Can I make an alternate MyMarshalByRefObject which would not inherit from MarshalByRefObject but would still act the same? Or is MarshalByRefObject receiving some special treatment by the .NET engine itself and the whole remoting feat is non-duplicatable by mere mortals?

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  • Conditional insert as a single database transaction in HSQLDB 1.8?

    - by Kevin Pauli
    I'm using a particular database table like a "Set" data structure, i.e., you can attempt to insert the same row several times, but it will only contain one instance. The primary key is a natural key. For example, I want the following series of operations to work fine, and result in only one row for Oklahoma: insert into states_visited (state_name) values ('Oklahoma'); insert into states_visited (state_name) values ('Texas'); insert into states_visited (state_name) values ('Oklahoma'); I am of course getting an error due to the duplicate primary key on subsequent inserts of the same value. Is there a way to make the insert conditional, so that these errors are not thrown? I.e. only do the the insert if the natural key does not already exist? I know I could do a where clause and a subquery to test for the row's existence first, but it seems that would be expensive. That's 2 physical operations for one logical "conditional insert" operation. Anything like this in SQL? FYI I am using HSQLDB 1.8

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  • How is timezone handled in the lifecycle of an ADO.NET + SQL Server DateTime column?

    - by stimpy77
    Using SQL Server 2008. This is a really junior question and I could really use some elaborate information, but the information on Google seems to dance around the topic quite a bit and it would be nice if there was some detailed elaboration on how this works... Let's say I have a datetime column and in ADO.NET I set it to DateTime.UtcNow. 1) Does SQL Server store DateTime.UtcNow accordingly, or does it offset it again based on the timezone of where the server is installed, and then return it offset-reversed when queried? I think I know that the answer is "of course it stores it without offsetting it again" but want to be certain. So then I query for it and cast it from, say, an IDataReader column to a DateTime. As far as I know, System.DateTime has metadata that internally tracks whether it is a UTC DateTime or it is an offsetted DateTime, which may or may not cause .ToLocalTime() and .ToUniversalTime() to have different behavior depending on this state. So, 2) Does this casted System.DateTime object already know that it is a UTC DateTime instance, or does it assume that it has been offset? Now let's say I don't use UtcNow, I use DateTime.Now, when performing an ADO.NET INSERT or UPDATE. 3) Does ADO.NET pass the offset to SQL Server and does SQL Server store DateTime.Now with the offset metadata? So then I query for it and cast it from, say, an IDataReader column to a DateTime. 4) Does this casted System.DateTime object already know that it is an offset time, or does it assume that it is UTC?

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  • Which isolation level should I use for the following insert-if-not-present transaction?

    - by Steve Guidi
    I've written a linq-to-sql program that essentially performs an ETL task, and I've noticed many places where parallelization will improve its performance. However, I'm concerned about preventing uniquness constraint violations when two threads perform the following task (psuedo code). Record CreateRecord(string recordText) { using (MyDataContext database = GetDatabase()) { Record existingRecord = database.MyTable.FirstOrDefault(record.KeyPredicate()); if(existingRecord == null) { existingRecord = CreateRecord(recordText); database.MyTable.InsertOnSubmit(existingRecord); } database.SubmitChanges(); return existingRecord; } } In general, this code executes a SELECT statement to test for record existance, followed by an INSERT statement if the record doesn't exist. It is encapsulated by an implicit transaction. When two threads run this code for the same instance of recordText, I want to prevent them from simultaneously determining that the record doesn't exist, thereby both attempting to create the same record. An isolation level and explicit transaction will work well, except I'm not certain which isolation level I should use -- Serializable should work, but seems too strict. Is there a better choice?

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  • Building "isolated" and "automatically updated" caches (java.util.List) in Java.

    - by Aidos
    Hi Guys, I am trying to write a framework which contains a lot of short-lived caches created from a long-living cache. These short-lived caches need to be able to return their entier contents, which is a clone from the original long-living cache. Effectively what I am trying to build is a level of transaction isolation for the short-lived caches. The user should be able to modify the contents of the short-lived cache, but changes to the long-living cache should not be propogated through (there is also a case where the changes should be pushed through, depending on the Cache type). I will do my best to try and explain: master-cache contains: [A,B,C,D,E,F] temporary-cache created with state [A,B,C,D,E,F] 1) temporary-cache adds item G: [A,B,C,D,E,F] 2) temporary-cache removes item B: [A,C,D,E,F] master-cache contains: [A,B,C,D,E,F] 3) master-cache adds items [X,Y,Z]: [A,B,C,D,E,F,X,Y,Z] temporary-cache contains: [A,C,D,E,F] Things get even harder when the values in the items can change and shouldn't always be updated (so I can't even share the underlying object instances, I need to use clones). I have implemented the simple approach of just creating a new instance of the List using the standard Collection constructor on ArrayList, however when you get out to about 200,000 items the system just runs out of memory. I know the value of 200,000 is excessive to iterate, but I am trying to stress my code a bit. I had thought that it might be able to somehow "proxy" the list, so the temporary-cache uses the master-cache, and stores all of it's changes (effectively a Memento for the change), however that quickly becomes a nightmare when you want to iterate the temporary-cache, or retrieve an item at a specific index. Also given that I want some modifications to the contents of the list to come through (depending on the type of the temporary-cache, whether it is "auto-update" or not) and I get completly out of my depth. Any pointers to techniques or data-structures or just general concepts to try and research will be greatly appreciated. Cheers, Aidos

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  • Creating a HTTP handler for IIS that transparently forwards request to different port?

    - by Lasse V. Karlsen
    I have a public web server with the following software installed: IIS7 on port 80 Subversion over apache on port 81 TeamCity over apache on port 82 Unfortunately, both Subversion and TeamCity comes with their own web server installations, and they work flawlessly, so I don't really want to try to move them all to run under IIS, if that is even possible. However, I was looking at IIS and I noticed the HTTP redirect part, and I was wondering... Would it be possible for me to create a HTTP handler, and install it on a sub-domain under IIS7, so that all requests to, say, http://svn.vkarlsen.no/anything/here is passed to my HTTP handler, which then subsequently creates a request to http://localhost:81/anything/here, retrieves the data, and passes it on to the original requestee? In other words, I would like IIS to handle transparent forwards to port 81 and 82, without using the redirection features. For instance, Subversion doesn't like HTTP redirect and just says that the repository has been moved, and I need to relocate my working copy. That's not what I want. If anyone thinks this can be done, does anyone have any links to topics I need to read up on? I think I can manage the actual request parts, even with authentication, but I have no idea how to create a HTTP handler. Also bear in mind that I need to handle sub-paths and documents beneath the top-level domain, so http://svn.vkarlsen.no/whatever/here needs to be handled by a single handler, I cannot create copies of the handler for all sub-directories since paths are created from time to time.

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  • Qt/C++ - confused about caller/callee, object ownership

    - by Isabel
    I am creating a GUI to manipulate a robot arm. The location of the arm can be described by 6 floats (describing the positions of the various arm joints. The interface consists of a QGraphicsView with a diagram of the arm (which can be clicked to change the arm position - adjusting the 6 floats). The interface also has 6 lineEdit boxes, to also adjust those values separately. When the graphics view is clicked, and when the line edit boxes are changed, I'd like the line edit boxes / graphics view to stay in synchronisation. This brings me to confusion about how to store the 6 floats, and trigger events when they're updated. My current idea is this: The robot arm's location should be represented by a class, RobotArmLocation. Objects of this class then have methods such as obj.ShoulderRotation() and obj.SetShoulderRotation(). The MainWindow has a single instance of RobotArmLocation. Next is the bit I'm more confused about, how to join everything up. I am thinking: The MainWindow has a ArmLocationChanged slot. This is signalled whenever the location object is changed. The diagram class will have a SetRobotArmLocation(RobotArmLocation &loc). When the diagram is changed, it's free to change the location object, and fire a signal to the ArmLocationChanged slot. Likewise, changing any of the text boxes will fire a signal to that ArmLocationChanged slot. The slot then has code to synchronise all the elements. This kind of seems like a mess to me, does anyone have any other suggestions? I've also thought of the following, does it have any merrit? The RobotArmLocation class has a ValueChanged slot, the diagram and textboxes can use that directly, and bypass the MainWindow directly (seems cleaner?) thanks for any wisdom!

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  • Trying to make a plugin system in C++

    - by Pirate for Profit
    I'm making a task-based program that needs to have plugins. Tasks need to have properties which can be easily edited, I think this can be done with Qt's Meta-Object Compiler reflection capabilities (I could be wrong, but I should be able to stick this in a QtPropertyBrowser?) So here's the base: class Task : public QObject { Q_OBJECT public: explicit Task(QObject *parent = 0) : QObject(parent){} virtual void run() = 0; signals: void taskFinished(bool success = true); } Then a plugin might have this task: class PrinterTask : public Task { Q_OBJECT public: explicit PrinterTask(QObject *parent = 0) : Task(parent) {} void run() { Printer::getInstance()->Print(this->getData()); // fictional emit taskFinished(true); } inline const QString &getData() const; inline void setData(QString data); Q_PROPERTY(QString data READ getData WRITE setData) // for reflection } In a nutshell, here's what I want to do: // load plugin // find all the Tasks interface implementations in it // have user able to choose a Task and edit its specific Q_PROPERTY's // run the TASK It's important that one .dll has multiple tasks, because I want them to be associated by their module. For instance, "FileTasks.dll" could have tasks for deleting files, making files, etc. The only problem with Qt's plugin setup is I want to store X amount of Tasks in one .dll module. As far as I can tell, you can only load one interface per plugin (I could be wrong?). If so, the only possible way to do accomplish what I want is to create a FactoryInterface with string based keys which return the objects (as in Qt's Plug-And-Paint example), which is a terrible boilerplate that I would like to avoid. Anyone know a cleaner C++ plugin architecture than Qt's to do what I want? Also, am I safely assuming Qt's reflection capabilities will do what I want (i.e. able to edit an unknown dynamically loaded tasks' properties with the QtPropertyBrowser before dispatching)?

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  • How do I get Facebook Application Login to work

    - by Javaaaa
    I just started making an application for Facebook, however I ran into problem early on. The first step I want people to do is to give permission to access their profile. All over the web are examples of how to do this with: $user_id = $facebook->require_login(); However, this is the way it works using the Old PHP API. I have downloaded and installed the new one in my application folder and it is not working anymore. My question is (and i really have been searching for an answer for a long time) what is the code to do this with the new API? (and related question: is it better to use the old API, or learn to work with the new one when I am just starting making apps right now) I have this code now; <?php // Awesome Facebook Application // // Name: - // require_once 'facebook-php-sdk/src/facebook.php'; // Create our Application instance. $facebook = new Facebook(array( 'appId' => $app_id, 'secret' => $app_secret, 'cookie' => true )); $loginUrl = $facebook->getLoginUrl(array( 'req_perms' => 'email,user_birthday,publish_stream,sms,status_update,user_location' )); echo "<p>hello, <fb:name uid=\"$user_id\" useyou=\"false\" />!</p>"; ?>

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  • java.lang.ClassNotFoundException in Netbeans. 5 hours to fix

    - by user1304281
    Hi I've got to submit an interpreter assignment tonight and all of a sudden it stopped working! It was working yesterday but now when I try to create a class instance at runtime I get classnotfoundexception. My project has no libraries or dependencies, I've written everything myself. I've googled around and it seems to be an issue with classpath but I've had no luck fooling with the project properties on netbeans. Here's some code: package interpreter; import interpreter.bytecode.ByteCode; import java.io.*; import java.lang.reflect.*; class ByteCodeLoader { //.... String codeClass = CodeTable.CodeTable.get(args[0]); ByteCode bytecode = (ByteCode)(Class.forName("interpreter.bytecode."+codeClass).newInstance()); //this throws exception } all of my ByteCodes are contained within a subpackage of interpreter called interpreter.bytecode. I'll be watching this thread so I can answer/clarify any questions immediately. Thanks for your time!

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  • java: libraries for immutable functional-style data structures

    - by Jason S
    This is very similar to another question (Functional Data Structures in Java) but the answers there are not particularly useful. I need to use immutable versions of the standard Java collections (e.g. HashMap / TreeMap / ArrayList / LinkedList / HashSet / TreeSet). By "immutable" I mean immutable in the functional sense (e.g. purely functional data structures), where updating operations on the data structure do not change the original data, but instead return a new instance of the same kind of data structure. Also typically new and old instances of the data structure will share immutable data to be efficient in time and space. From what I can tell my options include: Functional Java Scala Clojure but I'm not sure whether any of these are particularly appealing to me. I have a few requirements/desirements: the collections in question should be usable directly in Java (with the appropriate libraries in the classpath). FJ would work for me; I'm not sure if I can use Scala's or Clojure's data structures in Java w/o having to use the compilers/interpreters from those languages and w/o having to write Scala or Clojure code. Core operations on lists/maps/sets should be possible w/o having to create function objects with confusing syntaxes (FJ looks slightly iffy) They should be efficient in time and space. I'm looking for a library which ideally has done some performance testing. FJ's TreeMap is based on a red-black tree, not sure how that rates. Documentation / tutorials should be good enough so someone can get started quickly using the data structures. FJ fails on that front. Any suggestions?

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  • Querying the size of a drive on a remote server is giving me an error

    - by Testifier
    Here's what I have: public static bool DriveHasLessThanTenPercentFreeSpace(string server) { long driveSize = 0; long freeSpace = 0; var oConn = new ConnectionOptions {Username = "username", Password = Settings.Default.SQLServerAdminPassword}; var scope = new ManagementScope("\\\\" + server + "\\root\\CIMV2", oConn); //connect to the scope scope.Connect(); //construct the query var query = new ObjectQuery("SELECT FreeSpace FROM Win32_LogicalDisk where DeviceID = 'D:'"); //this class retrieves the collection of objects returned by the query var searcher = new ManagementObjectSearcher(scope, query); //this is similar to using a data adapter to fill a data set - use an instance of the ManagementObjectSearcher to get the collection from the query and store it ManagementObjectCollection queryCollection = searcher.Get(); //iterate through the object collection and get what you're looking for - in my case I want the FreeSpace of the D drive foreach (ManagementObject m in queryCollection) { //the FreeSpace value is in bytes freeSpace = Convert.ToInt64(m["FreeSpace"]); //error happens here! driveSize = Convert.ToInt64(m["Size"]); } long percentFree = ((freeSpace / driveSize) * 100); if (percentFree < 10) { return true; } return false; } This line of code is giving me an error: driveSize = Convert.ToInt64(m["Size"]); The error says: ManagementException was unhandled by user code Not found I'm assuming the query to get the drive size is wrong. Please note that I AM getting the freeSpace value at the line: freeSpace = Convert.ToInt64(m["FreeSpace"]); So I know the query IS working for freeSpace. Can anyone give me a hand?

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  • Finding What You Need in R: function arguments/parameters from outside the function's package

    - by doug
    Often in R, there are a dozen functions scattered across as many packages--all of which have the same purpose but of course differ in accuracy, performance, theoretical rigor, and so on. How do you gather all of these in one place before you start your task? So for instance: the generic plot function. Setting secondary ticks is much easier (IMHO) using a function outside of the base package, minor.tick(nx=n, ny=n, tick.ratio=n), found in Hmisc. Of course, that doesn't show up in plot's docstring. Likewise, the data-input arguments to 'plot' can be supplied by an object returned from the function 'hexbin', again, from a library outside of the base installation (where 'plot' resides). What would be great obviously is a programmatic way to gather these function arguments from the various libraries and put them in a single namespace. edit: (trying to re-state my example just above more clearly:) the arguments to plot supplied in the base package for, e.g., setting the axis tick frequency are xaxp/yaxp; however, one can also set a/t/f via a function outside of the base package, again, as in the minor.tick function from the Hmisc package--but you wouldn't know that just from looking at the plot method signature. Is there a meta function in R for this? So far, as i come across them, i've been manually gathering them in a TextMate 'snippet' (along with the attendant library imports). This isn't that difficult or time consuming, but i can only update my snippet as i find out about these additional arguments/parameters. Is there a canonical R way to do this, or at least an easier way? Just in case that wasn't clear, i am not talking about the case where multiple packages provide functions directed to the same statistic or view (e.g., 'boxplot' in the base package; 'boxplot.matrix' in gplots; and 'bplots' in Rlab). What i am talking is the case in which the function name is the same across two or more packages.

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  • What should I do with an over-bloated select-box/drop-down

    - by Tristan Havelick
    All web developers run into this problem when the amount of data in their project grows, and I have yet to see a definitive, intuitive best practice for solving it. When you start a project, you often create forms with tags to help pick related objects for one-to-many relationships. For instance, I might have a system with Neighbors and each Neighbor belongs to a Neighborhood. In version 1 of the application I create an edit user form that has a drop down for selecting users, that simply lists the 5 possible neighborhoods in my geographically limited application. In the beginning, this works great. So long as I have maybe 100 records or less, my select box will load quickly, and be fairly easy to use. However, lets say my application takes off and goes national. Instead of 5 neighborhoods I have 10,000. Suddenly my little drop-down takes forever to load, and once it loads, its hard to find your neighborhood in the massive alphabetically sorted list. Now, in this particular situation, having hierarchical data, and letting users drill down using several dynamically generated drop downs would probably work okay. However, what is the best solution when the objects/records being selected are not hierarchical in nature? In the past, of done this with a popup with a search box, and a list, but this seems clunky and dated. In today's web 2.0 world, what is a good way to find one object amongst many for ones forms? I've considered using an Ajaxifed search box, but this seems to work best for free text, and falls apart a little when the data to be saved is just a reference to another object or record. Feel free to cite specific libraries with generic solutions to this problem, or simply share what you have done in your projects in a more general way

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  • Spring validation has error in XML document from ServletContext resource

    - by user1441404
    I applied spring validation in my registration page .but the follwing error are shown in my server log of my app engine server. javax.servlet.UnavailableException: org.springframework.beans.factory.xml.XmlBeanDefinitionStoreException: Line 22 in XML document from ServletContext resource [/WEB-INF/spring/appServlet/servlet-context.xml] is invalid; nested exception is org.xml.sax.SAXParseException; lineNumber: 22; columnNumber: 30; cvc-complex-type.2.4.c: The matching wildcard is strict, but no declaration can be found for element 'property'. My code is given below : <?xml version="1.0" encoding="UTF-8"?> <beans:beans xmlns="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:beans="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.0.xsd > <beans:bean name="/register" class="com.my.registration.NewUserRegistration"> <property name="validator"> <bean class="com.my.validation.UserValidator" /> </property> <beans:property name="formView" value="newuser"></beans:property> <beans:property name="successView" value="home"></beans:property> </beans:bean> <beans:bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <beans:property name="prefix" value="/WEB-INF/views/" /> <beans:property name="suffix" value=".jsp" /> </beans:bean> </beans:beans>

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  • How strict should I be in the "do the simplest thing that could possible work" while doing TDD

    - by Support - multilanguage SO
    For TDD you have to Create a test that fail Do the simplest thing that could possible work to pass the test Add more variants of the test and repeat Refactor when a pattern emerge With this approach you're supposing to cover all the cases ( that comes to my mind at least) but I'm wonder if am I being too strict here and if it is possible to "think ahead" some scenarios instead of simple discover them. For instance, I'm processing a file and if it doesn't conform to a certain format I am to throw an InvalidFormatException So my first test was: @Test void testFormat(){ // empty doesn't do anything... processor.validate("empty.txt"); try { processor.validate("invalid.txt"); assert false: "Should have thrown InvalidFormatException"; } catch( InvalidFormatException ife ) { assert "Invalid format".equals( ife.getMessage() ); } } I run it and it fails because it doesn't throw an exception. So the next thing that comes to my mind is: "Do the simplest thing that could possible work", so I : public void validate( String fileName ) throws InvalidFormatException { if(fileName.equals("invalid.txt") { throw new InvalidFormatException("Invalid format"); } } Doh!! ( although the real code is a bit more complicated, I found my self doing something like this several times ) I know that I have to eventually add another file name and other test that would make this approach impractical and that would force me to refactor to something that makes sense ( which if I understood correctly is the point of TDD, to discover the patterns the usage unveils ) but: Q: am I taking too literal the "Do the simplest thing..." stuff?

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  • How to avoid hard coding credentials into Sharepoint webpart?

    - by SeeBees
    I am building a Sharepoint web part that will be used by all users. The web part connects to a web service which needs credentials with higher privileges than common users. I hard coded credentials in the web part's code. query.Credentials = new System.Net.NetworkCredential("username", "password", "domain"); query is an instance of the web service class This may not be a good approach. In regard with security, source code of the web apart is available to people who are not allowed to see the credential. This is bad enough, But is there any other drawback of this approach? A web part doesn't have a .config file associated. The .config file is in application-level of the sharepoint site, and I don't want to modify it for a single webpart. I wonder if there is a webpart-specific way to solve this problem? Say provide a WebBrowsable property to an admin so that he/she can set credentials. Is this possible? Thanks

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  • WCF newbie - how to install and use a SSL certificate?

    - by Shaul
    This should be a snap for anyone who's done it before... I'm trying to set up a self-hosted WCF service using NetTcpBinding. I got a trial SSL certificate from Thawte and successfully installed that in my IIS store, and I think I've got it correctly set up in the service - at least it doesn't exception out on me! Now, I'm trying to connect the client (this is still all on my dev machine), and it's giving me an error, "Message = "The X.509 certificate CN=ssl.mydomain.com, OU=For Test Purposes Only. No assurances., OU=IT, O=My Company, L=My Town, S=None, C=IL chain building failed. The certificate that was used has a trust chain that cannot be verified. Replace the certificate or change the certificateValidationMode. A certificate chain processed, but terminated in a root certificate which is not trusted by the trust provider." Ooookeeeey... now what? Client code (I want to do this in code, not app.config): var baseAddress = "localhost"; var factory = new DuplexChannelFactory<IMyWCFService>(new InstanceContext(SiteServer.Instance)); factory.Endpoint.Address = new EndpointAddress("net.tcp://{0}:8000/".Fmt(baseAddress)); var binding = new NetTcpBinding(SecurityMode.Message); binding.Security.Message.ClientCredentialType = MessageCredentialType.UserName; factory.Endpoint.Binding = binding; var u = factory.Credentials.UserName; u.UserName = userName; u.Password = password; return factory.CreateChannel()

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  • javascript watching for variable change via a timer

    - by DA
    I have a slide show where every 10 seconds the next image loads. Once an image loads, it waits 10 seconds (setTimeout) and then calls a function which fades it out, then calls the function again to fade in the next image. It repeats indefinitely. This works. However, at times, I'm going to want to over-ride this "function1 call - pause - function2 call - function1 call" loop outside of this function (for instance, I may click on a slide # and want to jump directly to that slide and cancel the current pause). One solution seems to be to set up a variable, allow other events to change that variable and then in my original function chain, check for any changes before continuing the loop. I have this set up: var ping = 500; var pausetime = 10000; for(i=0; i<=pausetime; i=i+ping){ setTimeout(function(){ console.log(gocheckthevariable()); console.log(i); pseudoIf('the variable is true AND the timer is done then...do the next thing') },i) } The idea is that I'd like to pause for 10 seconds. During this pause, every half second I'll check to see if this should be stopped. The above will write out to the console the following every half second: true 10000 true 10000 true 10000 etc... But what I want/need is this: true 0 true 500 true 1000 etc... The basic problem is that the for loop executes before each of the set timeouts. While I can check the value of the variable every half second, I can't match that against the current loop index. I'm sure this is a common issue, but I'm at a loss what I should actually be searching for.

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  • Rails: RESTful Find, Initialize, or Create

    - by Andrew
    I have an app that has Cities in it. I'm looking for some suggestions on how to RESTfully structure a controller so that I can lookup, initialize, and create city records via AJAX requests. For instance: Given a text field city_name A user enters the name of a City, like "Paris, France" The app checks this location to see if there is such a city in the database already If there is, it returns the city object If there is not, it returns a new record initialized with the name "Paris" and the country "France", and prompts the user to confirm they want to add this city to the database If the user says "Yes" the record is saved. If not the record is discarded and the form is cleared. Now, my first approach was to change the Create action to use find_or_create, so that an AJAX post to cities_path would result in either returning the existing city or creating it and returning it. That works ok... However, it would be better to setup controller actions that would take a string input, find , or else initialize and return, then only create if the user confirms the generated record is correct. The ideal scenario would put this all in one action so AJAX request can go to that url, the server responds with JSON objects, and javascript can handle things from there. I'd like to keep all the user-interaction logic client side, and also minimize the number of requests it takes to achieve this. Any suggestions on the cleanest, most RESTful way to accomplish this?

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  • Have you dealt with space hardening?

    - by Tim Post
    I am very eager to study best practices when it comes to space hardening. For instance, I've read (though I can't find the article any longer) that some core parts of the Mars rovers did not use dynamic memory allocation, in fact it was forbidden. I've also read that old fashioned core memory may be preferable in space. I was looking at some of the projects associated with the Google Lunar Challenge and wondering what it would feel like to get code on the moon, or even just into space. I know that space hardened boards offer some sanity in such a harsh environment, however I'm wondering (as a C programmer) how I would need to adjust my thinking and code if I was writing something that would run in space? I think the next few years might show more growth in private space companies, I'd really like to at least be somewhat knowledgeable regarding best practices. Can anyone recommend some books, offer links to papers on the topic or (gasp) even a simulator that shows you what happens to a program if radiation, cold or heat bombards a board that sustained damage to its insulation? I think the goal is keeping humans inside of a space craft (as far as fixing or swapping stuff) and avoiding missions to fix things. Furthermore, if the board maintains some critical system, early warnings seem paramount.

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